U.S. patent application number 13/543566 was filed with the patent office on 2012-11-01 for systems, methods and apparatus for calibrating differential air pressure devices.
Invention is credited to Edward Liou, Fritz Moore, Douglas Frank Schwandt, Mark A. Shughart, Robert Tremaine Whalen, Sean Tremaine Whalen.
Application Number | 20120277643 13/543566 |
Document ID | / |
Family ID | 40567692 |
Filed Date | 2012-11-01 |
United States Patent
Application |
20120277643 |
Kind Code |
A1 |
Whalen; Sean Tremaine ; et
al. |
November 1, 2012 |
SYSTEMS, METHODS AND APPARATUS FOR CALIBRATING DIFFERENTIAL AIR
PRESSURE DEVICES
Abstract
Methods, apparatus, and systems for calibrating differential air
pressure systems are described. The methods, apparatus, and systems
may be adapted for physical training of an individual, e.g. as a
training tool to improve performance or as a physical therapy tool
for rehabilitation or strengthening. The differential air pressure
systems comprise a chamber for receiving at least a portion of a
user's body. In one embodiment, a method for calibrating a
differential air pressure system for predicting effective body
weight of a user versus system pressure is described. In certain
variations, the methods, apparatus and systems may comprise
adjusting pressure in the system until one or more force values are
reached. The methods described herein may comprise determining a
relationship between body weight force and pressure, allowing the
user to set a pressure or a parameter correlated with pressure to
achieve a desired effective body weight.
Inventors: |
Whalen; Sean Tremaine;
(Mountain View, CA) ; Shughart; Mark A.; (Palo
Alto, CA) ; Schwandt; Douglas Frank; (Palo Alto,
CA) ; Whalen; Robert Tremaine; (Los Altos, CA)
; Liou; Edward; (Los Altos, CA) ; Moore;
Fritz; (Vacaville, CA) |
Family ID: |
40567692 |
Appl. No.: |
13/543566 |
Filed: |
July 6, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12761312 |
Apr 15, 2010 |
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13543566 |
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PCT/US2008/011807 |
Oct 15, 2008 |
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12761312 |
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60999061 |
Oct 15, 2007 |
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60999102 |
Oct 15, 2007 |
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60999101 |
Oct 15, 2007 |
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60999060 |
Oct 15, 2007 |
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Current U.S.
Class: |
601/151 |
Current CPC
Class: |
A63B 2022/002 20130101;
A63B 2208/0242 20130101; A63B 2208/0204 20130101; A63B 22/02
20130101; A63B 2220/20 20130101; A63B 2220/40 20130101; A63B
22/0023 20130101; A63B 22/0056 20130101; A63B 22/18 20130101; A63B
22/0605 20130101; A63B 2208/0228 20130101; A63B 2220/805 20130101;
A63B 2208/053 20130101; A61F 2007/0239 20130101; A63B 2209/10
20130101; A63B 2230/062 20130101; A63B 2230/01 20130101; A63B
22/0076 20130101; A61H 2009/0035 20130101; A63B 21/00181 20130101;
A63B 2230/06 20130101; A61H 2201/5058 20130101; A63B 2230/30
20130101; A61H 9/00 20130101; A63B 2071/0072 20130101 |
Class at
Publication: |
601/151 |
International
Class: |
A61H 7/00 20060101
A61H007/00 |
Claims
1. A method for applying pressure to a portion of an individual's
body comprising: receiving a portion of the individual's body in an
pressurizable chamber; producing a pressure inside the chamber;
increasing the chamber pressure to a predetermined threshold system
pressure; sensing the individual's weight in the chamber at at
least two pressures different from the threshold system pressure;
and generating a pressure and weight relationship for the
individual based at least in part on the individual's sensed weight
in the chamber at the at least two pressures.
2. The method of claim 1, further comprising regulating the
pressure in the chamber according to the pressure and weight
relationship for the individual.
3. The method of claim 1, wherein during the increasing step a
flexible portion of the pressurizable chamber expands in response
to the increasing chamber pressure.
4. The method of claim 1, further comprising: inflating a soft
shell portion of the pressurizable chamber at least partially
surrounding the portion of the individual's body in response to
increasing the chamber pressure to the predetermined threshold
system pressure.
5. The method of claim 1, further comprising offloading the
individual's weight in the chamber by increasing the chamber
pressure above the predetermined threshold system pressure.
6. The method of claim 1, the generating step further comprising:
adjusting the generated relationship with test data of various
subjects.
7. A system for applying pressure to a portion of an individual's
body comprising: a pressurizable chamber configured to receive a
portion of an individual's body and to apply pressure to the
portion during exercise; a weight sensor connected to the apparatus
for measuring the weight of the individual within the pressurizable
chamber and electronically communicating the measured weight to a
processor; a pressure sensor connected to the pressurizable chamber
for measuring the pressure within the pressurizable chamber and
electronically communicating the measured pressure to the
processor, the processor configured to pressurize the chamber to a
predetermined threshold system pressure, receive output from the
weight sensor at at least two pressure values different from the
threshold system pressure, and generate a measured weight and
pressure relationship for the individual.
8. The system of claim 7, wherein the processor is further
configured to regulate the system pressure according to the
measured weight and pressure relationship for the individual.
9. The system of claim 7, wherein the processor is further
configured to unweight the individual in the chamber according to
the measured weight and pressure relationship for the
individual.
10. The system of claim 7, wherein the processor is further
configured to adjust the measured weight and pressure relationship
with test data for various subjects.
11. The system of claim 7, wherein the weight sensor is further
configured to continuously measure the individual's weight while
pressure increases in the chamber.
12. The system of claim 7, wherein the weight sensor is further
configured to continuously measure the individual's weight during
exercise in the chamber.
13. A method for calibrating a differential pressure system
comprising: receiving a portion of the individual's body in an
expandable pressurizable chamber; producing a pressure inside a
chamber; sensing the individual's weight in the chamber at at least
two different pressures; and generating a pressure and weight
relationship for the individual from the sensed weight at the two
pressures; and refining the pressure and weight relationship for
the individual.
14. The method of claim 13, wherein refining the pressure and
weight relationship comprises measuring the weight experienced by
the user at additional pressure points and adjusting the
relationship based on the additional measured weight at the
additional pressure points.
15. The method of claim 13, wherein refining the pressure and
weight relationship further comprising increasing the range of
pressures over which weight is measured.
16. The method of claim 13, further comprising generating a
pressure and operation parameter relationship for pressure in the
system and an operation parameter of a device connected to the
differential pressure system.
17. The method of claim 16, wherein the operation parameter is an
incline of a treadmill in the chamber.
18. The method of claim 13, further comprising scaling the
generated pressure and weight relationship with test data from
various subjects.
19. The method of claim 13, further comprising repeating the
performance of one or more of the steps of calibrating the
differential pressure system pressure system while the individual
is operating an exercise device in the chamber.
20. The method of claim 13, wherein the refining step comprises
sensing and recording weight experienced by the individual at more
than two pressure points.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/761,312, filed Apr. 15, 2010, titled
"SYSTEMS, METHODS AND APPARATUS FOR CALIBRATING DIFFERENTIAL AIR
PRESSURE DEVICES," now Publication No. US-2011-0098157-A1, which is
a continuation of International Patent Application No.
PCT/US2008/011807, filed Oct. 15, 2008, titled "SYSTEMS, METHODS
AND APPARATUS FOR CALIBRATING DIFFERENTIAL AIR PRESSURE DEVICES,"
now Publication No. WO 2009/051750, which claims the benefit of
U.S. Provisional Patent Application No. 60/999,061, filed Oct. 15,
2007, titled "METHOD FOR DETERMINING UNLOADING SETTINGS IN A
DIFFERENTIAL AIR PRESSURE DEVICE VIA PAIN TITRATION," U.S.
Provisional Patent Application No. 60/999,102, filed Oct. 15, 2007,
titled "ADJUSTABLE SUPPORT FOR A DIFFERENTIAL AIR PRESSURE DEVICE,"
U.S. Provisional Patent Application No. 60/999,101, filed Oct. 15,
2007, titled "ADJUSTABLE ORIFICE FOR A DIFFERENTIAL AIR PRESSURE
DEVICE" and U.S. Provisional Patent Application No. 60/999,060,
filed Oct. 15, 2007, titled "METHOD FOR APPLYING A DIFFERENTIAL AIR
PRESSURE DEVICE IN THE FIELD OF PEDIATRICS, OBESITY, AND CARDIAC
DISEASES" each of which is herein incorporated by reference in its
entirety.
INCORPORATION BY REFERENCE
[0002] All publications and patent applications mentioned in this
specification are herein incorporated by reference to the same
extent as if each individual publication or patent application was
specifically and individually indicated to be incorporated by
reference.
FIELD
[0003] The present invention relates to differential air pressure
devices. More particularly, the present invention relates to
systems, methods and apparatus for calibrating a differential air
pressure device.
BACKGROUND
[0004] Gravity produces forces on the body. Methods of
counteracting these forces have been devised for therapeutic as
well as physical training uses. One way to counteract the effects
of gravity on a body is to attach elastic cords at the waist and/or
shoulder to produce either a positive or negative vertical force on
the individual.
[0005] Other systems may use differential air pressure to simulate
a low gravity effect. Some methods of calibrating devices that
counteract gravitational forces involve determining pressure
compared to body weight are described in U.S. Patent Application
Publication No. US-2007-0181121-A1 (now U.S. Pat. No. 7,591,795),
which is incorporated herein by reference in its entirety.
[0006] A need exists for improved devices and systems that can
reduce the effects of gravity on a body, and in particular for
improved devices and systems that can be calibrated, and methods
for calibrating such improved devices and systems.
SUMMARY OF THE DISCLOSURE
[0007] Methods, apparatus, and systems for calibrating differential
air pressure systems are described herein. In general, the
differential air pressure systems comprise a chamber for receiving
at least a portion of a user's body, e.g. a lower portion of the
body, including legs and hips. The methods, apparatus, and systems
in certain variations can be adapted for physical training of an
individual, e.g. as a training tool to improve performance, or as a
physical therapy tool for rehabilitation or strengthening. In some
embodiments, methods for calibrating a differential air pressure
system described here may be used for predicting effective body
weight of a user versus system pressure (pressure in a chamber
housing the user's body portion).
[0008] As used herein, the notation (x, y) in the context of a data
point is meant to referring to the value of y that corresponds to
that value of x. For example, as used herein, a (pressure, force)
data point refers to the force or load experienced by a user at
that system pressure.
[0009] In some embodiments, methods for calibrating a differential
air pressure apparatus or system comprise adjusting pressure in a
chamber that surrounds at least a portion of a user's body, e.g.
lower body, until body weight force on the user reaches a target
force value, and measuring the chamber pressure at that target
force value to generate a first (pressure, force) data point. The
methods include using the first (pressure, force) data point with
at least one other (pressure, force) data point to determine a
relationship between body weight force experienced by the user and
pressure in the chamber.
[0010] The target force value used in the methods may be a preset
force value, or the target force value may be determined by the
system for an individual user. When the target force value is
determined for an individual user, the target force value may be
stored by the system for subsequent use by the same individual
user.
[0011] In some variations, the at least one other (pressure, force)
data point may include a data point obtained at ambient pressure
(i.e. zero system differential pressure), and thus may be the data
point (0, user's body weight at ambient pressure).
[0012] Apparatus to predict effective body weight of a user as a
function of system pressure are described. The apparatus comprise a
differential air pressure system comprising a chamber configured to
surround at least a portion of a user's body, e.g. a user's lower
body. Processing logic coupled with the differential air pressure
system is configured to adjust pressure in the chamber until body
weight force on the user reaches a target force value, to measure
the chamber pressure at the target force value to determine a first
(pressure, force) data point, and to determine body weight force
experienced by the user as a function of pressure in the chamber
using the first (pressure, force) data point.
[0013] Other variations of methods for calibrating a differential
air pressure system are described herein. The methods comprise
adjusting pressure in a chamber of a differential air pressure
system, the chamber surrounding at least a portion of a user's
body. The methods comprise adjusting pressure in the chamber and
receiving a pain indication supplied by a user as a function of
pressure, and constructing a pressure versus pain relationship for
the user.
[0014] In some variations of the methods, the differential air
pressure system comprises an exercise machine, and the pressure
versus pain relation can be used to control operation of the
exercise machine. For example, in some variations the exercise
machine can comprise a treadmill, and the pressure versus pain
relationship can be used to control at least one of a speed of the
treadmill and an inclination of the treadmill. In some variations,
the exercise machine can comprise a stepper machine or a stationary
bicycle, and the pain versus pressure relationship can be used to
control a resistance of the stepper machine or the stationary
bicycle.
[0015] Other variations of apparatus to predict effective body
weight of a user versus system pressure are described herein. The
apparatus comprise a differential air pressure system that, in
turn, comprises a chamber configured to receive and surround at
least a portion of a user's body and a user interface. The
apparatus also comprises a processor coupled with the differential
air pressure system. The processor is configured to adjust pressure
in the chamber, to receive a pain indication from the user via the
user interface, and to construct a pain versus chamber pressure
relationship for the user. In some variations of the apparatus, the
pain versus chamber pressure relationship can be used to control
operation of an exercise machine that is included in the
differential air pressure system.
[0016] Still more methods for calibrating a differential air
pressure system for predicting effective body weight of a user
versus system pressure are described. The methods comprise
surrounding at least a portion of a user's body with a chamber of a
differential air pressure system, wherein the differential air
pressure system comprises a sensor configured to sense whether the
user's body within the chamber is in physical contact with a
surface. The methods further comprise adjusting pressure in the
chamber until a lift-off pressure is reached, wherein the lift-off
pressure is a pressure at which the sensor detects a break in the
physical contact between the user's body and the surface. The
methods comprise using the lift-off pressure to calibrate the
differential air pressure system. In some variations of the
methods, the lift-off pressure can be used to determine a chamber
pressure required to result in a desired effective body weight for
the user. In certain variations, the lift-off pressure can be used
to determine a maximum safety chamber pressure for the user to
prevent lift-off during usage.
[0017] Still more variations of apparatus for predicting effective
body weight of a user versus system pressure are described. In
these variations, the apparatus comprise a differential air
pressure system comprising a chamber configured to receive and
surround at least a portion of a user's body and a sensor
configured to detect whether the user's body within the chamber is
in physical contact with a surface. The apparatus further comprise
a processor coupled with the differential air pressure system,
wherein the process is configured to inflate the chamber of the
differential air pressure system and to measure a lift-off pressure
at which the sensor detects that physical contact between the
user's body and the user's body and the surface has been
broken.
[0018] Still more methods for calibrating a differential air
pressure system for predicting effective body weight of a user
versus system pressure are described herein. The methods comprise
using gas to pressurize a chamber in a differential air pressure
system, the chamber surrounding at least a portion of a user's
body. The methods comprise using a flow rate of the gas into and/or
out of the chamber to determine the pressure in the chamber. For
example, a valve position or opening size in an exhaust valve used
to control gas flow rate out of the chamber can be used to
determine pressure in the chamber. In some variations, power
(voltage and/or current) used by a blower pumping gas into the
chamber may be used to determine pressure in the chamber.
[0019] Additional methods for calibrating a differential air
pressure system for predicting effective body weight of a user
versus system pressure are described. The methods comprise
measuring an effective body weight of a user, the user having at
least a portion of the user's body surrounded by a chamber of a
differential air pressure system, by measuring a startup power
(voltage and/or current) of a motor of an exercise machine
supporting the user's body within the chamber. The methods comprise
correlating the effective body weight of the user with chamber
pressure. In some variations, the chamber pressure can be
determined using a flow rate of gas into and/or out of the
chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The accompanying drawings, which are incorporated into and
constitute a part of this specification, illustrate one or more
embodiments of the present invention and, together with the
detailed description, serve by way of illustration and not by
limitation to explain the principles and implementations of the
invention.
[0021] In the drawings:
[0022] FIG. 1 is a block diagram schematically illustrating an
example of a differential air pressure system that can be used for
exercise in accordance with one embodiment.
[0023] FIG. 2 is a block diagram schematically illustrating another
example of a differential air pressure system that can be used for
exercise in accordance with another embodiment.
[0024] FIG. 3 is a flow diagram schematically illustrating an
example of a method for calibrating a differential air pressure
system, e.g. a differential air pressure system as illustrated in
FIG. 1 or 2.
[0025] FIG. 4 is a flow diagram schematically illustrating another
example of a method for calibrating a differential air pressure
system, e.g. a differential air pressure system as illustrated in
FIG. 1 or 2.
[0026] FIG. 5 is a flow diagram schematically illustrating yet
another example of a method for calibrating a differential air
pressure system, e.g. a differential air pressure system as
illustrated in FIG. 1 or 2.
[0027] FIG. 6 is a flow diagram schematically illustrating still
another example of a method for calibrating a differential air
pressure system, e.g. a differential air pressure system as
illustrated in FIG. 1 or 2.
[0028] FIG. 7 is a flow diagram schematically illustrating another
example of a method for calibrating a differential air pressure
system, e.g. a differential air pressure system as illustrated in
FIG. 1 or 2.
[0029] FIG. 8 is a flow diagram schematically illustrating another
example of a method for calibrating a differential air pressure
system, e.g. a differential air pressure system as illustrated in
FIG. 1 or 2.
[0030] FIG. 9 provides a diagram of an example of a differential
air pressure system.
[0031] FIG. 10 provides a diagram of another example of a
differential air pressure system.
DETAILED DESCRIPTION
[0032] Those of ordinary skill in the art will realize that the
following detailed description of the present invention is
illustrative only and is not intended to be in any way limiting.
Other embodiments of the present invention will readily suggest
themselves to such skilled persons having the benefit of this
disclosure. Reference will now be made in detail to implementations
of the present invention as illustrated in the accompanying
drawings. The same reference indicators will be used throughout the
drawings and the following detailed description to refer to the
same or like parts. Unless clearly indicated otherwise explicitly
or by context, the singular referents such "a," "an", and "the" are
meant to encompass plural referents as well.
[0033] In the interest of clarity, not all of the routine features
of the implementations described herein are shown and described. It
will, of course, be appreciated that in the development of any such
actual implementation, numerous implementation-specific decisions
must be made in order to achieve the developer's specific goals,
such as compliance with application- and business-related
constraints, and that these specific goals will vary from one
implementation to another and from one developer to another.
[0034] In any variation described herein, any component, any
process step, and/or any data structure may be implemented using
any suitable type of operating system (OS), computing platform,
firmware, computer program, computer language, and/or
general-purpose machine described herein, presently known, or later
discovered. Variations of the methods described herein can, for
example, be run as a programmed process running on processing
circuitry. If used, such processing circuitry can take the form of
numerous combinations of processors and operating systems, or can
be configured as a stand-alone device. Methods and processes
described herein can be implemented as instructions executed by
such hardware, hardware alone, software, software alone or any
combination thereof. The software, if used, may be stored on a
program storage device readable by a machine.
[0035] In addition, those of ordinary skill in the art will
recognize that devices of a less general purpose nature, such as
hardwired devices, field programmable logic devices (FPLDs),
including field programmable gate arrays (FPGAs) and complex
programmable logic devices (CPLDs), application specific integrated
circuits (ASICs), or the like, may also be used without departing
from the scope and spirit of the inventive concepts disclosed
herein.
[0036] Embodiments of the present invention are described herein in
the context of systems, methods and apparatus for using and
calibrating air pressure in differential air pressure systems. In
the methods, the differential air pressure system comprises a
chamber for receiving and surrounding at least a portion of a
user's body, e.g. a user's lower body including legs and hips. Any
of the methods described herein for calibrating a differential air
pressure system can include predicting an effective body weight of
a user based on a system pressure, e.g. by extrapolation and or
interpolation using a relationship between body weight force and
chamber pressure determined during the calibration process.
[0037] When a portion of an individual's body is surrounded by a
sealed chamber, pressure in the chamber can be changed to adjust
force on the enclosed portion of the body, which in turn can affect
force on the user's body as a whole. For example, the chamber can
be pressurized to reduce gravitational force on the individual.
There, pressure in the chamber can function to unweight or unload
the individual from the normal effects of gravity. To control
and/or quantify the amount of force experienced by a user, e.g.
during exercise or rehabilitation, the pressure in the chamber can
be calibrated. In some variations, the chamber can be calibrated
relative to an individual user, e.g. relative to an individual
user's weight.
[0038] By controlling the pressure in a chamber of a differential
air pressure system with precision, the amount of offloading of the
user's weight can correspondingly be controlled with precision. For
example, for most individuals, the systems and methods described
herein can incrementally change a user's effective body weight by
as fine an adjustment as about 1% of the individual's body
weight.
[0039] In some embodiments, a user seal describes a construction of
a soft or flexible material, a stiff or rigid material, or a
combination thereof, to span the gap between a user and a chamber
in a sufficiently airtight manner. Various non-limiting examples of
constructions and methods of accomplishing a user seal are
described in U.S. Patent Application Publication No.
US-2007-0181121-A2 (now U.S. Pat. No. 7,591,795) and U.S. patent
application Ser. No. 12/761,316, filed Apr. 15, 2010, titled
"SYSTEMS, METHODS AND APPARATUS FOR DIFFERENTIAL AIR PRESSURE
DEVICES," now Publication No. US-2011-0098615-A1.
[0040] Furthermore, the differential air pressure systems and
related methods described herein may be adapted for use used in a
variety of different situations, such as, for example, dynamically
(e.g., while a user is in motion and not simply standing still) or
statically (e.g., while a user is stationary or relatively
stationary). In some embodiments, the differential air pressure
systems described herein may apply a positive pressure, where the
pressure inside the chamber of a differential air pressure system
is greater than the ambient pressure of the surroundings. In other
embodiments, a negative pressure may be applied to the pressure
chamber, the negative pressure being lower than that of the ambient
pressure of the surrounding environment.
[0041] Determining the gravitational force exerted by a user's
body, for example at ground level, may be accomplished using a
scale, one or more load cells, one or more pressure sensors, and/or
one or more other types of sensors having outputs that may be
directly or indirectly calibrated with respect to and/or correlated
to load. A measured force may be entered manually into a
calibration system in some variations, or may be automatically
collected and stored via electronics, which may in some instances
be aided by the use of software.
[0042] A pressure versus load curve may be constructed for an
individual by measuring and recording the force or load experienced
by the user as a function of pressure at two or more (pressure,
force) data points. Two such (pressure, force) data points
determine a linear relationship between load and pressure. However,
a linear relationship may become more refined or a nonlinear
relationship may be identified and refined by measuring and
recording load experienced by the user at more than two pressure
points. In some variations, the pressure-load relationship may be
refined by increasing the range of pressures over which load is
measured.
[0043] If desired, a pressure versus load curve can be generated
using pre-set or pre-defined pressure points. Such pre defined
pressure point(s) can be set in hardware or software for all users,
or can be determined by hardware, software, or a combination of
hardware and software based on some user metric (such as static
weight). For example, a user may enter his body weight at ambient
pressure, therefore producing one of the required (pressure, force)
data points to begin to construct the pressure-load line or curve.
Pressure may be varied discretely or continuously inside a pressure
chamber, and a user's weight may be measured at one or more chamber
pressures to collect the additional load value(s) to build up the
pressure-load curve. In some variations the pressure-load curve may
be adjusted and/or scaled based on test data of various subjects.
Some non-limiting examples of calibrated systems and related
methods that utilize a scale that is capable of making continuous
load measurements inside a chamber of a differential air pressure
system are described in U.S. Patent Application Publication No.
US-2007-0181121-A1 (now U.S. Pat. No. 7,591,795), which is hereby
incorporated by reference in its entirety, in particular with
respect to calibration.
[0044] In any of the variations described above or elsewhere
herein, a pressure versus load curve may be used as a predictive
algorithm (e.g., to predict a pressure at which a user will
experience a certain force, or a pressure at which a user will
experience a certain degree of unloading, e.g. as a percentage of
the user's body weight at ambient pressure or as a force offset by
which the user's body weight an ambient pressure is reduced).
[0045] Examples of differential air pressure systems are
illustrated in FIGS. 1 and 2. FIG. 1 is a block diagram
schematically illustrating an example of a differential air
pressure system. There, system 100 is configured for applying
pressure to a lower body portion 106 of an individual 101 in
accordance with one embodiment. The system 100 includes a chamber
102 and a controller 103 for adjusting (increasing or decreasing)
the pressure inside the chamber 102. In some variations, the
controller 103 may be configured for maintaining the pressure
inside the chamber 102. Any suitable controller or controller
configuration described herein, now known or later developed can be
used to adjust (increase or decrease) the pressure inside the
chamber. If the pressure controller 103 is configured to maintain
pressure inside the chamber 102, a negative feedback control system
may be used in some variations, e.g. as described in U.S. Patent
Application Publication No. US-2007-0181121-A1 (now U.S. Pat. No.
7,591,795), which is incorporated by reference herein in its
entirety.
[0046] In the variation illustrated in FIG. 1, the chamber 102
includes an aperture 104 for receiving the lower body portion 106.
Although in this particular example aperture 104 is oriented along
a vertical axis, in other variations, other locations or
orientations of an aperture for receiving a body portion may be
used. Any suitable type of shell may be used to form the chamber
102 in the system 100. The chamber 102 may include a soft or
flexible shell or a stiff or rigid shell, or a shell that includes
a portion formed from a soft or flexible material and a portion
formed from a stiff or rigid. material. Some non-limiting examples
of suitable shells are described in U.S. Patent Application
Publication No. US-2007-0181121-A1 (now U.S. Pat. No. 7,591,795)
and U.S. patent application Ser. No. 12/761,316, filed Apr. 15,
2010, titled "SYSTEMS, METHODS AND APPARATUS FOR DIFFERENTIAL AIR
PRESSURE DEVICES," now Publication No. US-2011-0098615-A1, each of
which is incorporated by reference herein in its entirety.
[0047] In variations in which the chamber 102 has a soft or
flexible shell or a shell including a soft or flexible portion and
a stiff or rigid portion, the soft shell or soft portion of the
shell may be inflated or deflated accordingly. In certain
variations, the chamber 102 may occupy an approximately
hemi-spherical shape or half-ovoid shape when a soft shell or soft
portion of a shell is inflated. FIG. 1 illustrates one embodiment
where the chamber 102 includes a top portion of a sphere or
ovoid-like shape with a planar cross-section as a base 108 of the
chamber 102. The base 108 can supports the individual user 101 in
any position, e.g. standing or sitting, such as standing upright or
sitting upright. It should be recognized a similar system may be
constructed with the user in a horizontal position, e.g. by
rotating the aperture 104 by about 90 degrees clockwise or
counter-clockwise.
[0048] The soft shell or soft shell portion may be made of any
suitable flexible material, e.g. a fabric (woven or nonwoven), a
thin sheet of plastic, leather (natural or synthetic), and the
like. In some variations, the soft shell or soft shell portion may
be made from sufficiently airtight fabric that may be woven or
non-woven. In some cases, a fabric used in a shell may be slightly
permeable to air, but be sufficiently airtight so as to allow a
desired degree of pressure to build up in the chamber. While the
chamber is deflated, the soft shell or shell portion may allow for
the lower body portion 106 to be positioned within the aperture
104. The aperture 104 may include for example an elliptical or
circular shape and flexible fabric or other type of flexible
material for accommodating various shapes of waistline of the
individual lower body 106.
[0049] The height of the soft shell or shell portion may be
adjusted using a variety of techniques. In one example, a height of
a soft shell (e.g. one made from fabric) may be altered by using
straps to pull down on the top portion of the shell. In another
example, the aperture 104 may include a rigid ring (not shown) that
surrounds the waist or torso of the individual 101. The height of
the chamber 102 can thus be adjusted by raising or lowering the
rigid ring.
[0050] One or more bars (not shown) may be provided as part of the
system 100 and may be configured to encompass at least a portion of
the flexible shell below the waist of the individual 101. Such bar
or bars may be configured to hold a flexible portion of shell in
along the sides of the chamber to limit expansion, therefore
keeping the shell close to the torso of the individual 101 allowing
for comfortable arm swing. The bar or bars may limit the ability of
a flexible shell from expanding into an undesired shape, e.g. a
spherical shape. The bar or bars may have any suitable
configuration. For example, in some variations, two parallel bars
may be provided along sides. In other variations, one U-shaped bar
may be used, where the base of the U-shaped bar may be positioned
in front of the user. Similarly, a rigid shell or partially rigid
shell may be configured to allow for keeping the arms of the
individual 101 from touching or otherwise being interfered with by
the rigid shell while the individual 101 is moving (walking or
running) through a contoured shape, e.g. a saddle shape. Additional
examples of height-adjustable shells and variable shape shells for
chambers are described in U.S. Patent Application Publication No.
US-2007-0181121-A1 (now U.S. Pat. No. 7,591,795) and U.S. patent
application Ser. No. 12/761,316, filed Apr. 15, 2010, titled
"SYSTEMS, METHODS AND APPARATUS FOR DIFFERENTIAL AIR PRESSURE
DEVICES," now Publication No. US-2011-0098615-A1, each of which is
incorporated by reference herein in its entirety.
[0051] The system 100 may also include a rear entrance walkway (not
shown) to facilitate entrance and exit to and from the chamber 102.
A rear entrance walkway may in some variations include a step. In
variations of the chamber 102 having a soft shell or soft shell
portion, such a rear entrance walkway, if present, may be used a
means for supporting the soft shell or soft shell portion in an
deflated state, e.g. so that it is easier to attach a seal 110 to
the individual 101. A walkway may also serve as a safety platform
in case the shell of the chamber 102 rips (in the case of a
flexible shell, e.g. a fabric shell) or breaks (in the case of hard
shell). A walkway may also include one or more holding bars for the
individual 101 to hold onto to support the individual or to prevent
the individual from falling.
[0052] With respect to variations of the chamber 102 having a hard
shell, the chamber 102 may include a door (not shown) or other type
of opening that allows the individual 101 to enter and exit the
chamber 102. For example, a door can be used, where the door can
swing open, swing down, or slide open. A door can be comprised of
fabric, plastic, leather or other type of flexible material that
can be closed in a sufficiently airtight manner with a zipper,
snaps, and/or other type of closure (e.g. Velcro.TM. type hook and
loop closures). In some variations, aperture 104 may be created by
moving two halves of chamber 102 apart and back together like a
clam-shell or a cockpit. Additionally, the height of hard shell may
be adjusted based on the height of individual 101.
[0053] Some variations of adjustable shells for use in differential
air pressure systems such as that illustrated in FIG. 1 are
described in U.S. patent application Ser. No. 12/761,316, filed
Apr. 15, 2010, titled "SYSTEMS, METHODS AND APPARATUS FOR
DIFFERENTIAL AIR PRESSURE DEVICES," now Publication No.
US-2011-0098615-A1, which is incorporated by reference herein in
its entirety.
[0054] A seal 110 is provided between the user's lower body 106 and
the aperture 104 at or near the torso or the waistline of the
individual user 101. In accordance with one embodiment, the seal
110 includes a plurality of openings/leaks around the torso of the
individual 101 to cool the individual 101 and/or to better control
distribution of pressure around the torso of the individual 101.
For example, leaks positioned in front by the stomach of the
individual 101 may help with the bloating due to ballooning of a
flexible waist seal under pressure. Such deliberate leaks may be
implemented by sewing non-airtight fabrics or other materials, or
by forming holes in the shell (hard or soft) of the chamber 102.
The seal 110 can be made of a substantially airtight material
and/or non-airtight material. The seal 110 can be implemented with
a skirt, pants (shorts), or a combination of both.
[0055] In accordance with one embodiment, the seal 110 may include
a separable seal closure. Non-limiting examples of separable seal
closures include zippers, snaps, Velcro.TM. type hook and loop
closures, kayak style attachment (e.g. using a zipper) over a rigid
lip that is attached to the shell, clamps, and deformable loops. In
some variations, the seal 110 may include means for anchoring to
the individual lower body 106 and means for attaching to the
aperture 104. Means for anchoring to the user's body may include,
for example, Velcro.TM. type straps that extend around the
circumference of a user's thighs for adjustment to accommodate
different thigh sizes, and a belt that keeps the seal anchored at
the hipbone. Other examples of means for anchoring to the user's
body may include a high friction material that seals against the
user's body and remains anchored because of a high friction
coefficient. The seal 110 may be breathable and washable. In
accordance with another embodiment, the seal 110 may seal up to the
individual chest, and in some variations the seal may extend from
the user's waist region up to the chest. In some variations, the
seal 110 may include a skirt-type seal. Additional non-limiting
examples of seals are described in U.S. Patent Application
Publication No. US-2007-0181121-A1 (now U.S. Pat. No. 7,591,795)
and U.S. patent application Ser. No. 12/761,316, filed Apr. 15,
2010, titled "SYSTEMS, METHODS AND APPARATUS FOR DIFFERENTIAL AIR
PRESSURE DEVICES," now Publication No. US-2011-0098615-A1, each of
which is incorporated by reference in its entirety.
[0056] An optional exercise machine 112 may be at least partially
housed within the chamber 102. Any suitable exercise machine may be
used, e.g. a treadmill, a stationary bicycle, a rowing machine, a
stepper machine, an elliptical trainer, a balance board, and the
like. The exercise machine 112 may be, for example, a treadmill
having an adjustable height, inclination, and speed. Any parameter
of the exercise machine can be adjusted based on a dimension of the
individual user 101. For example, the height, position within the
chamber, seat position, handgrip position, and the like, of the
exercise machine 112 can be adjusted to accommodate a dimension of
the individual 101. Those of ordinary skill in the art will
appreciate that the treadmill shown is not intended to be limiting
and that other exercise machines can be used without departing from
the inventive concepts herein disclosed.
[0057] In some variations, a differential air pressure system
includes a pressurizable chamber without an exercise machine 112.
In these variations, the chamber 102 may be used without any
exercise machines, e.g. as a means to improve jumping ability,
balance, or general movement.
[0058] Any suitable type of controller 103 can be used for
adjusting the pressure inside the chamber 102. As stated above, the
controller 103 in some variations is configured to maintain the
pressure in the chamber 102, e.g. if the controller 103 is
configured as a negative feedback control system. In certain
variations, the controller 103 includes an intake system 114 and an
outtake system 116. In some cases, the controller 103 may include a
pressure sensor 120, a processor 122, or a control panel 118, or
any combination of two or more of the above.
[0059] In the variation illustrated in FIG. 1, intake system 114
includes an input port 124 for receiving a gas (for example, air),
a pressure source 126 (pump or blower), and an output port 128. The
gas flow from pressure source 126 may be unregulated. Pressure
source 126 can be turned on or off. In accordance with another
embodiment, the pressure source 126 may include a variable fan
speed that can be adjusted for controlling the incoming airflow to
the chamber 102. Pressure source 126 pumps gas from input port 124
to output port 128.
[0060] In the variation illustrated in FIG. 1, outtake system 116
includes an input port 130 for receiving gas from chamber 102, a
pressure regulating valve 132, and an output port 134 to ambient
pressure. The pressure regulating valve 132 controls the exhaust
flow from the chamber 102. The input port 130 is an output port of
the chamber 102. Gas leaves the chamber 102 via the output port
134. In accordance with another embodiment, a safety exhaust port
(not shown) may be connected to the chamber 102 for allowing gas to
exit the chamber 102 in case of pressure increasing beyond a limit
such as a safety limit, e.g. in an emergency or a system
failure.
[0061] In some variations, the differential air pressure system as
illustrated in FIG. 1 includes a user interface system for allowing
the individual 101 or an operator to interact with the system 100
via the processor 122. Any suitable user interface may be used,
e.g. a touch sensor such as a touch screen, a handheld button, a
handheld control box, or a voice-activated user interface. In
certain variations, a control panel 118 includes a user interface
system. The user interface and/or the control panel may be
interfaced with the processor 122 in a wireless configuration or
hardwired. In some variations, the individual 101 may use a
touch-screen interface (not shown) on the control panel 118, e.g.
to program the pressure within the chamber 102, and/or to control
one or parameters of the exercise machine, e.g. the speed, the
inclination, the resistance and/or the height of the exercise
machine 112. The control panel 118 may also be used by the
individual 101 to calibrate the system for correct body weight
and/or to input a desired factor or parameter to determine an
intensity of exercise. For example, the user may specify that he
wants to exercise at a certain fraction of his body weight, or
offset his body weight by a certain number of pounds, or exercise
at a certain heart rate or blood pressure, or exercise at a certain
pain level. Non-limiting examples of calibration processes are
described in further detail below.
[0062] In one embodiment, an optional pressure sensor 120 is
connected to the chamber 102 for measuring a differential pressure
between the pressure inside the chamber 102 and the ambient
pressure. Those of ordinary skill in the art will appreciate that
the pressure sensor 120 shown is not intended to be limiting and
that other types of pressure transducer or pressure measuring
sensors can be used without departing from the inventive concepts
herein disclosed. The pressure sensor 120 communicates its
measurements to the processor 122. As described herein, system 100
does not need to include pressure sensor to accomplish the
calibration process as described in the some of the variations of
methods and systems below.
[0063] In some variations, the controller 103 can be configured to
use input from the pressure sensor 120 to control the pressure
source 126 and/or the pressure regulating valve 132. The processor
122 can communicate with the user interface or control panel 118,
if present. An example of the algorithm of the processor 122 is the
processor 122 receives an input from the control panel 118. For
example, the input may include a desired pressure within the
chamber 102, a desired percentage of body weight of the individual,
an amount of weight to offset the user's body weight, and/or a pain
level. The processor 122 can be configured to operate the pressure
source 126 and/or the regulated valve 132 using a negative feedback
loop, circuit, or system. The processor 122 can in certain
variations monitor the pressure inside the chamber 102 with input
from the pressure sensor 120. Based on the measurements from the
pressure sensor 120 and the input from user, e.g. via the control
panel 118, the processor 122 sends a drive signal to the regulated
valve 132 and/or the pressure source 126 to increase or decrease
the exhaust flow through the chamber 102 so as to maintain the
pressure within chamber 102 as close as possible to the desired
pressure. The desired pressure may be pre-set in some variations,
and in some variations may be received from the control panel 118
or derived from information received from user, e.g. via the
control panel. The pressure (positive or negative) inside the
chamber 102 produces an upward or downward force on the individual
101 resulting in a lighter or heavier sensation.
[0064] The processor 122 may in some variations communicate with
the exercise machine 112. The processor 122 may receive one or more
input parameters via the control panel 118 for the exercise machine
112. For example, the exercise machine 112 may include a treadmill
with speed or inclination adjusted by the processor 122 based on
the pressure sensed inside the chamber 102.
[0065] In accordance with some embodiments, the system 100 may be
controlled to monitor and/or maintain various performance
parameters, such as to achieve a constant stride frequency. In some
variations, the processor 122 may be configured to receive input
from one or more user performance parameter sensors, e.g. heart
rate, blood pressure, pain level, stride length, cadence or stride
frequency, foot strike pressure, and the like. One or more
parameters of the exercise machine such as speed, resistance and/or
pressure inside the chamber may be adjusted in response to the one
or more user parameters. For example, a sensor may be placed on a
treadmill to detect the impact from the user's feet on the
treadmill and compare with subsequent values to measure the time
duration between strides. The machine can then adjust pressure,
tilt, speed, etc. to maintain a specific stride rate.
[0066] In accordance with yet another embodiment, the system 100
may include an acceleration/deceleration sensor coupled to the
individual 101 sensing whether the user is speeding up or slowing
down. Those of ordinary skill in the art will recognize that there
are many ways of implementing such a sensor. The processor 122
receives the measurement from the acceleration/deceleration sensor
and may send a signal to increase or decrease the speed of the
treadmill in response to the measurement in combination with
increasing or decreasing the pressure inside the chamber 102.
[0067] The processor 122 may also include a data storage (not
shown) such as a database storing various data and/or executable
programs that may be selected or programmed in by the individual
101 or by an operator via the control panel 118. The data storage
may include a repository of data that may be used to control the
system 100. For example, while receiving data from one or more
sensors (including the pressure sensor, performance sensors of the
individual, a safety sensor, etc. . . . ) the processor 122 may
determine that one or more parameters has reached a pre-set limit
or a dangerous level. The processor 122 then alters the pressure
and/or a parameter of the exercise machine 112, e.g. a resistance
or speed, e.g. the speed of the treadmill. For example, a trainer
could set a maximum speed, heart rate, resistance, cadence, blood
pressure, or pain parameter for the individual 101. The processor
122 would ensure that that parameter is not to be exceeded. The
data storage may also be used to store past performance data and
personal records for different protocols and the system 100 could
allow the individual 101 to run against previous performance data
or personal records.
[0068] The data storage may also include various training programs
based on the selection from the control panel 118. The processor
122 could then limit activity levels to non-harmful ranges for the
individual 101 based on one variable, a combination of variable, or
all variables. The data storage may also be able to log and record
the performance and activities of the individual 101 as well as
store any calibration data so that the individual 101 trainer,
therapist or the like need not perform that the calibration process
for every use of the differential air pressure system.
[0069] FIG. 2 is a block diagram schematically illustrating a
system 200 for applying pressure to a lower body portion 106 the
individual 101 in accordance with another embodiment. The system
200 includes the chamber 102 and controller 202 for adjusting
(increasing or decreasing) the pressure inside the chamber 102. In
some variations controller 202 can be configured to maintain
pressure inside the chamber 102. An example of controller 202 is a
negative feedback control system.
[0070] Controller 202 for adjusting (and in some variations
maintaining) the pressure inside the chamber 102 includes an intake
system 204. In some variations, the controller includes a user
interface such as described in connection with FIG. 1. In certain
variations, a user interface may be included as part of a control
panel 118. In some variations, controller 202 includes a pressure
sensor 120, and a processor 206.
[0071] In the variation illustrated in FIG. 2, the intake system
204 includes an input port 208 for receiving a gas (for example,
air), a regulated pressure source 210, and an output port 212. The
regulated pressure source 210 pumps gas from the input port 208 to
the output port 212. The output port 212 is also an input port into
the chamber 102. Gas is pumped in and out of the chamber 102 via
the output port 212. The inflow of air is regulated via the
regulated pressure source 210. The regulated pressure source 210
includes an adjustable exhaust valve for controlling the gas flow
rate through output port 212. In accordance with some variations,
the regulated pressure source may include a pump having an
adjustable fan blade size or fan speed. The gas flow rate can be
adjusted by varying the fan speed or fan blade size. A safety
exhaust port (not shown) may be connected to the chamber 102 for
allowing gas to exit the chamber 102 in case of a pre-set limit is
reached, e.g. in an emergency or a system failure.
[0072] The processor 206 communicates with the control panel 118,
if present, and the pressure sensor 120 to control the regulated
pressure source 210. An example of the algorithm of processor 122
is the processor 206 receives an input from the user, e.g. via
control panel 118. For example, the input may include a desired
pressure inside the chamber 102, a body weight of the individual, a
factor to determine a percentage of body weight that the individual
would like to experience during exercise, a weight offset the user
would like use to offset his weight at relative to weight at
ambient pressure, a pain limit, a heart rate, and/or a blood
pressure, and the like. In the variation illustrated in FIG. 2, the
processor 206 can operate the regulated pressure source 210 using a
negative feedback loop, circuit, or system. The processor 206
monitors the pressure inside the chamber 102 with the pressure
sensor 120. Based on the measurements from the pressure sensor 120
and the input from the user (e.g. via control panel 118), the
processor 122 sends a drive signal to the regulated pressure source
210 to increase or decrease the gas flow through the chamber 102 so
as to maintain the pressure within chamber 102 as close as possible
to the desired pressure received from the user, e.g. via control
panel 118. The pressure (positive or negative) inside the chamber
102 produces an upward or downward force on the individual 101
resulting in a lighter or heavier sensation.
[0073] In some variations, the processor 206 may communicate with
an exercise machine 112 at least partially housed inside the
chamber 102. Any suitable exercise machine 112 may be used, e.g. as
described above in connection with FIG. 1. In some variations, no
exercise machine is used. The processor 206 may receive one or more
input parameters (e.g. speed, resistance, cadence, incline, workout
algorithm, or the like) from the user, e.g. via control panel 118,
for the exercise machine 112. For example, the exercise machine 112
may include a treadmill with speed or incline adjusted by the
processor 206 based on the pressure sensed inside the chamber
102.
[0074] The processor 206 may also include a data storage (not
shown) such as a database storing various data and/or executable
programs that may be selected or programmed in by the individual
101 or an operator via the control panel 118. The data storage may
include a repository of data that may be used to control the system
200. For example, while receiving data from all sensors, the
processor 206 may determine that one or more parameters have
reached a pre-set limit or a dangerous level. The processor 206
then alters the pressure and/or one or more parameters of the
exercise machine 112, e.g. the speed of a treadmill. For example, a
trainer or physical therapist could set a maximum speed parameter
for the individual 101. The processor 206 could limit that speed so
that it is not exceeded. The data storage may be used to store past
performance data and/or personal records for different protocols
and the system 200 could allow the individual 101 to train against
previous performance data or personal records.
[0075] The data storage may also include various training programs
based on a selection from the control panel 118. The processor 206
can in some variations limit one or more activity levels of the
individual to non-harmful levels based on one or more variable,
e.g. based all the variables. The data storage may also be able to
log and record the performance and activities of individual
101.
[0076] In one embodiment, methods for calibrating a differential
air pressure system, e.g. as illustrated in FIG. 1 or 2, comprise
adjusting pressure in the chamber until force experienced by the
user reaches a target force value, and measuring the pressure at
which the target force value is reached to obtain a first
(pressure, force) data point, where the force value is the target
force value and the pressure is the chamber pressure measured when
that target force value is reached. The methods may in some
variations comprise using the first (pressure, force) data point to
determine (e.g. by extrapolation and/or interpolation) a
relationship between body weight force experienced by the user and
chamber pressure. An example of such a process variation is
illustrated in FIG. 3.
[0077] The process variation illustrated in FIG. 3 does not require
a scale or other device that is capable of continuous load
measurement be placed inside the pressure chamber to enable a
person's weight be measured as a function of pressure. Instead, a
force such as a user's body weight can be sensed inside the
chamber, and a pressure at which the force reaches a preset force
level can be determined. For example, the system may include a
platform or surface against which the user exerts body weight
force. A pressure at which the user's body weight reaches a target
force value (i.e. a known weight which may in some variations be
predetermined) can be measured to generate a first (pressure,
force) data point, where the force is the target force value and
the pressure is the differential chamber pressure measured at the
target force value. The comparison between the force on the user
and the target force value or known weight can be accomplished
using any suitable mechanism or setup, e.g. by use of a simple
balance or counterweight configuration. The first (pressure, force)
data point can then be used in combination with at least one more
(pressure, force) data point to generate a pressure-load curve for
the system. In some variations, a user's body weight at ambient
pressure can be used as one of the additional (pressure, load) data
points. One or more additional (pressure, load) data points can be
obtained by measuring one or more additional pressures at which the
user's body weight in the pressure chamber reaches one or more
other target force values. At least one of the target force values
used in the calibration process can be preset in some variations,
e.g. preset as to all users of a differential air pressure system.
In other variations, one or more of the target force values can be
determined or selected by the system for a particular individual.
For example, a system may select a larger target force value based
in input from a user indicating a relatively high normal body
weight, and a smaller target force value based on input for a user
indicating a relatively low normal body weight. The (pressure,
load) data points so gathered can be used to generate a
pressure-load curve. In some variations the pressure-load curve may
be adjusted and/or scaled based on test data of various subjects.
Pressure-load data points may for example be obtained for a set of
subjects using a differential air pressure system equipped with
scales or load cells in the pressure chamber, and a pressure sensor
coupled to the chamber.
[0078] Referring now to FIG. 3, such a calibration process begins
by processing logic adjusting pressure in a pressure chamber that
is sealed around at least a portion of a user's body until an
initial force or load target value is reached, and measuring the
pressure (or a parameter that can be related to pressure such as
exhaust valve position or power draw by a pressure source, as is
described herein) at which the force or load target value is
reached (processing block 302). The process may be performed by
processing logic that may comprise hardware (circuitry, dedicated
logic, etc.), software (such as is run on a general purpose
computer system or a dedicated machine), or a combination of both
hardware and software. In some variations, processing logic resides
in processor 122 of FIG. 1 or processor 206 of FIG. 2. The force or
load against which the system is calibrated can be a force exerted
on a surface, or other sensing point, of the system. A surface
against which a force is exerted may be in any orientation relative
to the system.
[0079] In some variations, a measurement of force experienced by
the user can be obtained from the user's body weight on a surface
at the base of the system. In some variations, the force
measurement is obtained from an upper surface, such as, for
example, a hanging load measurement device. For example, FIG. 9
provides an illustration of one variation of a differential air
pressure system 900 comprises a hanging load measurement device
901. There, the device 901 comprises one or more force sensors 902
(e.g. one or more springs, tension gauges, and the like) attached
to a user 904 that has at least a portion of his body enclosed in a
chamber 906 of the differential air pressure system 900. The
difference between P.sub.1 (pressure inside the chamber) and
P.sub.2 (pressure outside the chamber) alters force experienced by
the user 904. The pressure P.sub.1 inside the chamber 906 can be
increased until the force experienced by the user reaches a target
force F.sub.1, as sensed by the one or more force sensors 902. As
described above, an initial load value may be the full user body
weight measured and entered at ambient pressure in the system. The
entering of the data may be done by the user or measured by the
system with no pressure differential in the chamber (i.e. at
ambient pressure).
[0080] A second target force value is then set and the
corresponding system pressure (or a parameter that can be related
to pressure such as exhaust valve position or power draw by a
pressure source, as is described herein) is recorded when the force
sensed (e.g. the user's body weight) reaches the target force value
(processing block 304). Step 304 may be repeated as many times as
desired. In some variations, the target force value or values can
be set in hardware and/or software for all users. In certain
variations, the predetermined force targets values are determined
by hardware, software, or a combination of hardware and software
based on a user metric (such as static full body weight at ambient
pressure). For example, the force targets may be created based on a
percentage of the static weight of the user at ambient pressure. In
some variations, the pressure is varied in the system of FIG. 1 or
FIG. 2 by processing logic until a force/load exerted by a user's
body on a surface of the system is effectively equal to, just
greater than, or just less than a pre-set force value.
[0081] A correlation can then be computed using the two or more
(pressure, load) data points (processing block 306) (i.e. a
load-pressure curve is generated). In some variations the
pressure-load curve may be adjusted and/or scaled based on test
data of various subjects. In some embodiments, the correlation
allows the system to create a predictive pressure vs. load curve to
adjust a user's effective body weight in the chamber by adjusting
the pressure in the chamber.
[0082] In some variations, processing logic returns to processing
block 302 to repeat the sense and calibration process 300. In some
variations, the processing logic may return to processing block 302
after completing processing block 304 to gather more (pressure,
load) data points prior to calculating a correlation of pressure
and body weight (processing block 306). The calibration process may
be optionally repeated for several other target force values, for
establishment of additional pressure values, e.g. a broader or
narrower range of pressure values, or to enable a more accurate
correlation between force and pressure to be created. For example,
multiple (pressure, load) data points may be desirable in certain
circumstances because of the non-linearity of the system at lower
body weights.
[0083] Because force is utilized as a control variable, while
pressure is adjusted until measured force meets force target
values, the process of FIG. 3 may be extended to systems and
methods where target load values (which may be preset) are measured
via springs, deformable elastic materials, or other known force
application schemes as described herein, known in the art, or later
developed.
[0084] As discussed earlier, variations of systems and methods that
adjust pressure until sensed force reaches one or more target force
values and measuring the pressure (or a parameter that can be
related to pressure such as exhaust valve position or power draw by
a pressure source, as is described herein) associated with the one
or more target force values may be advantageous in certain
circumstances. For example, such systems and methods may use a
force sensing means that need not quantify force, e.g., it may not
be necessary to read continuous force values. Instead, such systems
need only be capable of sensing force relative to a target force
value, e.g. with a balance, spring, counterweight, elastic, and the
like. The result may be a system with reduced electrical and/or
mechanical complexity thereby increasing reliability of the system
while reducing system cost.
[0085] FIG. 4 is a flow diagram 400 schematically illustrating
another example of a method for calibrating a differential air
pressure system, e.g. a system illustrated in FIG. 1 or FIG. 2. The
process can be performed by processing logic that may comprise
hardware (circuitry, dedicated logic, etc.) software (such as is
run on a general purpose computer system or a dedicated machine),
or a combination of both hardware and software. In some
embodiments, processing logic resides in processor 122 of FIG. 1 or
processor 206 of FIG. 2.
[0086] Referring to FIG. 4, the process begins with a force/load
exerted by the user on a spring or compliant surface with which the
load is subsequently sensed or measured (processing block 402). The
compliant surface or spring may be used to sense or measure
force/load at ambient pressure or at a system pressure. In one
embodiment, the force is measured as deformation of a board, which
may for example comprise two platforms, where the platforms are
separated by a spring or spring-like material.
[0087] Any system or method where deflection is measured to
indicate or correlate with applied user load shall be considered
within the scope of this invention. In some variations, when a
spring deforms (e.g., when a user exerts a force on the spring such
as by standing on the platforms), the spring deflection may be
measured and correlated with applied user load. In some variations,
one or more sensors, for example one or more capacitance meters or
sensors, may be placed along the deforming axis of the spring to
obtain a deflection measurement, which can then be correlated to
load via a known compliance of the spring and output of the sensor,
e.g. capacitance to indicate a distance between two plates. Any
suitable type of sensor to sense deflection may be used, e.g.
displacement sensor(s), optical sensor(s), or Hall effect magnet
sensor(s).
[0088] It should be noted that in the method variations described
and illustrated in connection with FIG. 4, deflection can be
measured by a suitable sensor quantitatively in a continuous
manner, or deflection can be sensed or measured as relative to a
reference value; for instance, a spring may be preset to unload to
a known force value and a switch (e.g. binary switch) may alert a
processor when that degree of reduction of force has been achieved.
In some variations, a certain degree of loading may be known from a
certain amount of deflection, because the sensors may be preset to
known load values that are correlated by the compliance of the
spring or board the sensor is coupled to. In another example, two
switches may be set, and the pressure may be varied until the first
switch is triggered, and pressure may be adjusted until the other
switch is triggered. By knowing the difference in force required to
trigger each switch and the pressures at which each switch was
triggered, an appropriate pressure-load curve or correlation can be
obtained. In certain variations, the system may contain multiple
ones of such trigger switches.
[0089] In some variations, a (pressure, load) data point obtained
at ambient pressure/full body weight may be entered by the user or
by the system and used in combination with one additional
(pressure, load) data point obtained by measuring deflection of a
board or spring of a user in the chamber at a single pressure to
construct a simple linear pressure-load relationship. In some
variations, multiple sensors may be used to measure deflection of
the board, spring or compliant surface, and the data from the
multiple sensors recorded for a more accurate construction of a
force/load versus pressure curve.
[0090] After the first data point is obtained, the pressure in the
chamber can be varied until a target force value is reached
(processing block 404). In this particular variation, the target
force value is in the form of a known deflection based on the
compliance of the system. Once the target deflection is achieved,
the pressure value (or a value that can be linked to pressure, such
as an exhaust valve setting or power draw by a pressure source, as
described herein) is measured. This process may in some variations
be repeated multiple times to obtain multiple data points. The
repetition of the process may occur after processing block 404, as
shown with a dashed line in FIG. 4, or after processing block
406.
[0091] A correlation between the chamber pressure and body weight
force as measured by the deflection is created (processing block
406). In one embodiment, the correlation allows the system to
create a predictive pressure vs. load curve to adjust a user's
effective body weight in the chamber by adjusting the pressure in
the chamber. In certain variations, multiple deflection
measurements of a board or spring or other compliant surface may be
obtained at multiple pressures to generate more (load, pressure)
data points, which may in turn lead to a more accurate linear or
nonlinear pressure-load curve. In some variations the pressure-load
curve may be adjusted and/or scaled based on test data of various
subjects.
[0092] FIG. 5 is a flow diagram 500 schematically illustrating
another example of a method for calibrating a differential pressure
system, e.g. the systems illustrated FIG. 1 or FIG. 2. The process
can be performed by processing logic that may comprise hardware
(circuitry, dedicated logic, etc.), software (such as is run on a
general purpose computer system or a dedicated machine), or a
combination of both. In one embodiment, processing logic resides in
processor 122 of FIG. 1 or processor 206 of FIG. 2.
[0093] Referring to FIG. 5, the process begins by processing logic
receiving data indicating the system is at zero differential
pressure (ambient pressure) (processing block 502). In one
embodiment, the data may be received from the user, e.g. via
control panel 118, a scale and/or switch (e.g. a pressure sensitive
switch that can detect to a desired degree of accuracy when a
weight is pressing down on the switch) coupled with the system, or
if the system has the pressure source turned off and therefore
knows there is no pressure being applied in the system, etc.
[0094] Pressure can then adjusted in the system until no user body
weight is detected on a scale or switch (processing block 504). In
one embodiment, a lift-off pressure in the chamber corresponds to
the pressure at which the user is sufficiently separated from the
measuring surface, or a sufficiently low force is exerted by the
user on the measuring surface so that reasonable accuracy is
obtained when assuming this pressure measurement value corresponds
to an effective zero user weight. Any suitable sensor or sensor
type may be used to detect when the user exerts no detectable force
on the measuring surface, e.g. a weight sensor, or a displacement
sensor or other type of sensor to detect a separation between the
user and a surface of the system such as an optical sensor, Hall
effect magnetic sensor, resistive sensor, capacitive sensor, or the
like. In another embodiment, data received from a user, e.g. by a
control panel or handheld user control interface to send a signal
to alert processing logic that the user has been lifted off of the
surface (e.g., for example, a user pressing a button to halt the
increase in pressure).
[0095] A correlation between pressure and force (which can be
expressed as a percent of a user's body weight) is then created
(processing block 506). As discussed in connection with other
embodiments describe herein, the correlation allows the system to
create a predictive pressure vs. load curve to adjust a user's
effective body weight by adjusting the pressure in the chamber. The
curve may be assumed to be a straight line with two (pressure,
load) data points used as end pressure and load intercept points,
or the curve may assume a non-linear relationship. In some
variations the pressure-load curve may be adjusted and/or scaled
based on test data of various subjects.
[0096] As discussed with reference to FIG. 5, the first (pressure,
load) data point used can be at zero differential pressure and 100%
effective body weight measured at ambient pressure, and the second
(pressure, load) data point can be at a full pressure measurement
at which 0% effective body weight value is sensed.
[0097] The processing logic can be supplied with at least two
(pressure, load) data points to construct pressure-load
relationship (e.g. a line in the case that two pressure-load data
points are supplied). The logic can then calibrate the system, e.g.
relative to the body weight of the user at ambient pressure, such
as a percentage of the ambient pressure body weight, or as an
offset from the ambient pressure user body weight. For example, a
user may enter his body weight to give an estimate of absolute
effective body weight, not just an effective percent body weight,
and the system may operate in terms of absolute weight units, not
just relative body weight units, e.g. percent body weight.
[0098] FIG. 6 is a flow diagram 600 schematically illustrating
another example of a method for calibrating a differential pressure
system, e.g. as illustrated in FIG. 1 or FIG. 2. The process can be
performed by processing logic that may comprise hardware
(circuitry, dedicated logic, etc.), software (such as is run on a
general purpose computer system or a dedicated machine), or a
combination of both. In one embodiment, processing logic resides in
processor 122 of FIG. 1 or processor 206 of FIG. 2.
[0099] Referring to FIG. 6, the process begins by processing logic
receiving data indicating a user's body weight at ambient pressure
(processing block 602). In one embodiment, the weight is received
when a user steps on a scale coupled with processing logic, from a
control panel, etc. In another embodiment the weight is simply
entered by the user as his known body weight at zero system
pressure. In another embodiment the process begins with processing
604, and requires at least one repetition of the processing blocks
604 and 606 to collect at least two (pressure, load) data points
required to form a pressure vs. applied load curve for the
user.
[0100] The force exerted by the user on a surface of the system
relative to one or more objects of known weight is measured
(processing block 604). Processing logic then adjusts system
pressure until the force exerted by the user equals the known
weight(s) (processing block 606). In one embodiment, pressure is
adjusted until force exerted by the user equals the known weight(s)
of the object within some reasonable tolerance. Processing logic
may optionally repeat processing blocks 604 and 606 multiple
times.
[0101] In the embodiment discussed in FIG. 6, calibration is
enabled by a form of scale system. An example of such a scale
system may be a beam that the user stands on that pivots at a point
between the user and the object of known weight. The user is then
unloaded (e.g., pressure is adjusted) until the force or torque
applied by the user and the object cancel. At this point, the user
is known to weigh some ratio of the weighted object by taking into
account the relative distances from the pivot and the mass of the
beam. An example of a scale system is illustrated in FIG. 10. There
a differential air pressure system 1000 includes a chamber 1002,
with at least a portion of body of the user 1004 surrounded by the
chamber 1002. The differential air pressure system 1000 comprises a
scale system 1010. The scale system 1010 comprises a platform 1012
that supports the user 1004. The platform 1012 is coupled to one
end 1014 of a beam 1016. A spring 1024 with a known spring constant
k.sub.s connects an end 1020 of beam 1016 that is opposite end 1014
(that supports the user) to the ground or other reference point.
The beam 1016 is balanced on a pivot block 1018 at pivot point
1022. One or more sensors 1026 are placed on the beam 1016. The
sensor(s) 1026 may be any suitable type of sensor (e.g. a tilt
sensor, a torque sensor, and the like). As the user exerts force on
the end 1014 of the beam 1016, the beam pivots at pivot point 1022,
causing a spring 1024 to compress or expand. Pressure P.sub.1 in
the chamber 1002 may be adjusted until the force exerted by the
user on the beam 1016 causes the beam to balance out the force due
to the spring 1024. In certain variations, any one of the spring
constant k.sub.s of the spring 1024 may be changed, the length of
the beam 1016 may be changed, and the position of the pivot point
1022 along the beam 1016 may be changed. The weight of the user may
be measured in the manner using multiple objects having known
weights and the associated pressure values stored to create the
pressure versus load curve for that individual. Furthermore, as
discussed herein, a user may also enter his normal body weight at
zero system pressure as one valid (pressure, load) data-point to be
used in the creation of a prediction curve.
[0102] In some variations a differential air pressure system, e.g.
as illustrated in FIG. 1 or FIG. 2, may be calibrated by user pain
level relative to pressure. Such calibration using pain may be
performed instead of or in addition to calibrating effective body
weight relative to pressure. FIG. 7 is a flow diagram 700
schematically illustrating an example of a method for calibrating a
differential air pressure system by the use of user pain level
relative to pressure. The process can be performed by processing
logic that may comprise hardware (circuitry, dedicated logic,
etc.), software (such as is run on a general purpose computer
system or a dedicated machine), or a combination of both. In one
embodiment, processing logic resides in processor 122 of FIG. 1 or
processor 206 of FIG. 2.
[0103] Referring to FIG. 7, the process begins by processing logic
adjusting system pressure (processing block 702). In one
embodiment, system pressure of the bag is increased to a
predetermined initial or threshold level, and then adjusted
according to user pain as discussed below. In another embodiment,
system pressure is increased from zero system pressure rather than
from a predetermined initial or threshold level.
[0104] Data is received that indicates a user's current pain level
(processing block 704). In one embodiment, as the pressure in the
bag is increased, a user can input how much pain they feel. The
user may answer questions, turn a dial on a control panel 118,
press a button of control panel 118 to determine a threshold or
level of pain (e.g. a user may select a button to indicate a level
on a pain scale, which may for example be a pain scale from 0
indicating no pain to 10 indicating intolerable pain), respond to
prompts supplied by the system (e.g. by pressing a number on a
number pad, verbally, or any kind of touch sensor, or use any other
known method of user input). In one embodiment, this pain
measurement can be taken either statically or dynamically, meaning
the user can be standing still or in motion. Steps 702 and 704 in
the process 700 may be repeated until a level of pain indicted on a
pain scale and/or a maximum pain threshold is determined to be
appropriate for the user. The process may be halted by any signal
from the user if pain is too great.
[0105] Pressure is then correlated with the data indicating user
pain level relative to pressure (processing block 706). In one
embodiment, the system correlates pressure with pain to enable the
system to automatically adjust pressure to allow a user to move
based on comfort level. Furthermore, the correlation may enable the
pressure differential system, e.g. as illustrated in FIG. 1 or FIG.
2, to adjust one or more workout metrics, such as speed of a
treadmill, incline, resistance, pressure regulation, pressure
level, etc., to adjust the workout based on known user pain
tolerances.
[0106] In certain variations of differential air pressure systems,
such as those described in connection with FIG. 1 or FIG. 2,
pressure in the chamber can be controlled by controlling flow of
gas into and/or out of the pressure chamber, i.e. using an air
intake valve to control flow into the pressure chamber, air exhaust
valve to control flow out of the pressure chamber, or a combination
thereof. Thus, by knowing how gas flow into and/or out of the
chamber affects pressure, pressure in the chamber can be determined
without a direct pressure measurement.
[0107] In certain variations of differential air pressure systems,
such as those described in connection with FIG. 1 or FIG. 2, load
experienced by a user in a pressure chamber can be determined
without measuring the individual's weight. For example, where
pressure chamber contains an active exercise system, such as a
treadmill, the startup power in a motor could be used to determine
effective user body weight, rather than via user input or a scale
coupled with differential air pressure system. Without any load, a
motor consumes a certain amount of power to start the exercise
system. When a user is impeding starting of the motor, such as by
standing on the belt of a treadmill or by having their legs on a
bike, the amount of power it takes to start the system
increases.
[0108] Thus, one or more system resources other than measured
chamber pressure and can be utilized for calibrating a system to
determine user load. For example, by controlling gas intake,
exhaust flow, or some combination of thereof, a correlation can be
found between pressure and the expenditure of that resource. Power
(voltage or current) consumed by the pressure source (e.g. blower)
may be correlated to pressure in a chamber. In some variations,
position of an exhaust valve may be correlated to chamber pressure.
In some variations, a startup power (voltage and/or current) needed
to operate an exercise machine (such as a treadmill, elliptical
trainer, or stepper) may be correlated with user applied load
(which incorporates user's body weight). Such data from system
components or devices that is other than pressure in the chamber or
a direct or indirect measure of a user's body weight but that can
be linked to pressure or load can be used to generate a set of
(pressure, load) data points with which to calibrate a differential
pressure system. The calibration curve may be generated using these
system device parameters other than pressure or load as
appropriate. For example, the chamber pressure may be calibrated
versus startup power needed to operate an exercise machine, or load
in the chamber (e.g. as a percentage of user's ambient pressure
body weight) may be calibrated versus exhaust valve position or
power delivered to a pressure source. In some variations, startup
power needed to operate an exercise machine may be calibrated
versus a valve position or power delivered to a pressure
source.
[0109] FIG. 8 is a flow diagram 800 schematically illustrating an
example of a method for calibrating a differential air pressure
system, e.g. as illustrated in FIG. 1 and FIG. 2. The process can
be performed by processing logic that may comprise hardware
(circuitry, dedicated logic, etc.), software (such as is run on a
general purpose computer system or a dedicated machine), or a
combination of both hardware and software. In some embodiments,
processing logic resides in processor 122 of FIG. 1 or processor
206 of FIG. 2.
[0110] As discussed above, in some variations, the system device
used to calibrate a differential air pressure system may be a motor
of an exercise machine such as a treadmill motor, an elliptical
trainer motor, or a stepper machine motor, an exhaust valve
position that controls air exhaust from the chamber, or input
blower control power (voltage or current), etc. While the device(s)
are adjusted, pressure or load is monitored directly or indirectly
as appropriate.
[0111] As discussed above, chamber pressure can be a known function
of a system device parameter, e.g. exhaust valve position or power
consumed by the pressure source (blower). For example, chamber
pressure can be automatically or manually correlated with exhaust
valve position or power consumed by the pressure source. Such a
correlation can, for example, be established during a system design
stage, or an initial setup stage. Further, load can be a known
function of a system device parameter, e.g. startup power of an
exercise machine. For example, startup power of an exercise machine
can be automatically or manually monitored as a function of user
applied load, e.g. during system design or as an initial setup
stage. If the correlation of chamber pressure or load with a system
device parameter is accomplished automatically processing logic can
control adjustment of the system device parameter and monitor
pressure chamber or user applied load in response.
[0112] In some variations, it may not be necessary to determine a
continuous relationship between the device system parameter and
pressure or load. For example, it may be sufficient to know the
relationship between a device system parameter and pressure or load
at a single point, e.g. exhaust valve position or power consumption
by a pressure source can be determined for a single chamber
pressure. Startup power by an exercise machine can be determined at
a single user load value.
[0113] Once it is known how a system device parameter correlates
with pressure or load at one or more points, the differential air
pressure system can be calibrated using that system device
parameter. One example of such a process is illustrated in flow
chart form in FIG. 8. There, the process begins by adjusting one or
more devices of a system, where a parameter of that device has been
correlated with pressure or load (processing block 802). In the
variation illustrated in FIG. 8, the device parameter can be
adjusted until it reaches a value corresponding to a known pressure
or load value (processing block 804). The user data in terms of
pressure, load or a related quantity can be determined from the
known monitored values (processing block 806). The process steps
804 and 806 may be repeated as many times as desired, as indicated
by the dashed lines.
[0114] By using processing logic to monitor startup energy, power,
voltage, amperage, inertia, torque, or any combination of these at
different levels of applied load, processing logic may determine
the change in the user's effective body weight while one or more of
the system devices are adjusted. For example, a differential air
pressure system using the method illustrated in FIG. 8 may set an
initial target startup current value and adjust chamber pressure
until the target value is reached. The system may repeat this
process multiple times, storing both the pressure and the target
value each time. The system may then use a known correlation
between startup current and load in conjunction with the measured
pressures to create a pressure vs. effective body weight curve for
the user. It should be clear that startup current is but one
example, and other system device parameters may be used in the
methods described above, e.g. in connection with FIG. 8.
[0115] In another embodiment, where the system device parameter is
a system exhaust, an exhaust valve position versus chamber pressure
can be pre-calibrated for the system. The system can determine one
or more opening sizes of the exhaust valve, or one or more valve
positions to adjust pressure in the chamber to reach one or more
preset loads. Because the pressure versus load curve may be
determined and used as a predictive function of exhaust valve
position and effective body weight, eliminating the need for a
pressure sensor.
[0116] In yet another embodiment, where the control is a system
input blower control voltage or current, the voltage or current to
the blower can be changed by processing logic to find a voltage or
current to adjust pressure in the chamber to reach one or more
preset loads. Therefore, voltage or current draw by the blower can
be calibrated to effective body weight curve in a similar manner.
Here again, the calibration process utilizes flow rate of gas into
pressure chamber of the system to control pressure, and utilizes a
known system conversion between blower power consumption and
pressure, but does not require a direct measurement of
pressure.
[0117] While embodiments and applications of this invention have
been shown and described, it would be apparent to those skilled in
the art having the benefit of this disclosure that many more
modifications than mentioned above are possible without departing
from the inventive concepts herein. For example, the present
invention may be applicable to containing any part of the body,
such as the upper body, torso area, etc. The invention, therefore,
is not to be restricted except in the spirit of the appended
claims. Furthermore, embodiments of the systems, apparatuses, and
methods described herein may be practiced individually, or in
combination. Many different combinations would be apparent to those
skilled in the art having the benefit of this disclosure.
[0118] It shall be understood that any of the concepts described
herein may be joined together, or combined, to form a useful
invention. For example, any combination of the calibration and
sensing methods described herein may be implemented to accomplish a
system that performs calibration. For the sake of brevity, and to
avoid obscuring the individual concepts discussed above, not all
combinations of the inventions described herein have been listed,
but combinations shall be held within the scope of this patent.
Additionally, it shall be understood that systems that described a
pressurized chamber may be construed to include both positive and
negative pressure configurations. Positive verses negative pressure
may require different configurations of the inventions but such
modifications from those explicitly described herein shall be
considered within the scope of this patent.
* * * * *