U.S. patent application number 11/202046 was filed with the patent office on 2006-02-16 for device for determining the position of a sliding seat.
Invention is credited to Timothy William Baker.
Application Number | 20060035753 11/202046 |
Document ID | / |
Family ID | 33017554 |
Filed Date | 2006-02-16 |
United States Patent
Application |
20060035753 |
Kind Code |
A1 |
Baker; Timothy William |
February 16, 2006 |
Device for determining the position of a sliding seat
Abstract
A device that measures the position of a sliding seat used in
rowing, canoeing or kayaking. Digitally encoded strips are fixed to
the boat and sensors are fixed to a sliding seat such that the
sensors detect the encoded strips. A microprocessor analyses the
sensor outputs and determines the seat position. The seat position
is transmitted from the seat to the boat or other location via a
non contact link such as radio.
Inventors: |
Baker; Timothy William;
(Derby, GB) |
Correspondence
Address: |
TIM BAKER
35 WEST AVENUE
DERBY, DERBYSHIRE
DE1 3HS
GB
|
Family ID: |
33017554 |
Appl. No.: |
11/202046 |
Filed: |
August 12, 2005 |
Current U.S.
Class: |
482/51 |
Current CPC
Class: |
B63B 2029/043 20130101;
B60N 2/06 20130101; A63B 2220/30 20130101; G01P 3/486 20130101;
G01D 5/34715 20130101; G01D 5/2497 20130101; B63B 34/26 20200201;
A63B 2069/068 20130101; B60N 2/002 20130101; A63B 69/06 20130101;
B63B 29/04 20130101 |
Class at
Publication: |
482/051 |
International
Class: |
A63B 22/00 20060101
A63B022/00; A63B 71/00 20060101 A63B071/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 14, 2004 |
GB |
GB 0418213.5 |
Claims
1. A device for determining the position of a sliding seat
comprising, one or more encoded strips attached to a boat or part
of a boat, one or more sensors attached to a sliding seat such that
the sensors detect the encoded strip and provide one or more
channels of encoded information, and a method a transmitting the
output of the sensor(s) from the seat to the boat or other
location.
2. A device for determining the position of a sliding seat
according to claim 1, in which a detector is fixed to the seat
comprising sensors and supporting electronic circuits, a
microcontroller, a power source and a transmission method.
3. A device for determining the position of a sliding seat
according to claim 1, in which a receiver, designed to detect the
signal transmitted from the seat is fixed to the boat.
4. A device for determining the position of a sliding seat
according to claim 1, in which the encoded strips are attached to
the boat, the rails that the sliding seat runs in or a support
bracket.
5. A device for determining the position of a sliding seat
according to claim 1, in which the encoded strips are mounted at
any angle to the horizontal in order to suit the design.
6. A device for determining the position of a sliding seat
according to claim 1, in which a receiver, designed to detect the
signal transmitted from the seat is fixed to another boat, shore
station or other location.
7. A device for determining the position of a sliding seat
according to claim 1, in which a single channel of digital encoded
information is used to determine the speed of a sliding seat.
8. A device for determining the position of a sliding seat
according to claim 1, in which two channels of digital encoded
information are used to determine the speed and direction of
movement of a sliding seat.
9. A device for determining the position of a sliding seat
according to claim 1, in which three channels of digital encoded
information are used to determine the speed, direction of movement
of a sliding seat and to fix the position of the seat in absolute
terms as it passes a given point.
10. A device for determining the position of a sliding seat
according to claim 1, in which multiple channels of digital encoded
information are used to determine the absolute position of a
sliding seat by providing a unique output combination for each
potential position of the seat.
11. A device for determining the position of a sliding seat
according to claim 1, in which each channel of digital encoded
information is provided by a single sensor and single encoded
strip.
12. A device for determining the position of a sliding seat
according to claim 1, in which multiple channels of digital encoded
information are provided by multiple sensors and a single encoded
strip.
13. A device for determining the position of a sliding seat
according to claim 1, in which the encoded strip comprises sections
with properties that are good and poor infra-red reflectors and the
sensor comprises an infra-red source and detector.
14. A device for determining the position of a sliding seat
according to claim 1, in which the encoded strip comprises sections
of high and low magnetic field and the sensor is a hall effect
sensor.
15. A device for determining the position of a sliding seat
according to claim 1, in which the encoded strip and sensor are a
non-contact method of digital encoding.
16. A device for determining the position of a sliding seat
according to claim 1, in which one or more analogue strips, with
varying properties along the length of he strip are used to
determine the seat position.
17. A device for determining the position of a sliding seat
according to claim 1, in which the method of transmitting the
sensor output from the boat is a non-contact method.
18. A device for determining the position of a sliding seat
according to claim 1, in which the method of transmitting the
sensor output from the boat is a radio link, ultrasonic link or
infra-red link.
19. A device for determining the position of a sliding seat
according to claim 1, in which raw data from the sensors is
transmitted from the seat.
20. A device for determining the position of a sliding seat
according to claim 1, in which a microcontroller analyses the
sensor output(s) and converts this information to a value
representative of the distance of the seat from a known point and
this value is transmitted from the seat.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from the United Kingdom
application GB 0418213.5.
[0002] The invention relates to a sliding seat in the sports of
rowing, canoeing and kayaking.
[0003] In the sports of rowing, canoeing and kayaking, sliding
seats are often used to allow the athlete to use their legs, in
addition to their arms and body, to propel the boat. With the feet
fixed in position relative to the boat, the legs can bent during
the recovery phase of a stroke and then straightened during the
drive phase of the stroke, when the blade or paddle is in the
water, such that the legs help to propel the boat.
[0004] Such seats are typically mounted on wheels that slide in
smooth tracks. This system constrains the movement of the seat to a
single dimension and reduces frictional losses.
[0005] For the purposes of teaching and high performance coaching
it is desirable to be able to measure the position of such a
sliding seat as it varies with time.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0006] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM
LISTING COMPACT DISC APPENDIX
[0007] Not Applicable
BACKGROUND OF THE INVENTION
[0008] The invention relates to a sliding seat in the sports of
rowing, canoeing and kayaking. This could apply to water based
craft or land based simulators such as rowing machines or
ergometers.
[0009] In the sports of rowing, canoeing and kayaking, sliding
seats are often used to allow the athlete to use their legs, in
addition to their arms and body, to propel the boat. With the feet
fixed in position relative to the boat, the legs can bent during
the recovery phase of a stroke and then straightened during the
drive phase of the stroke, when the blade or paddle is in the
water, such that the legs help to propel the boat.
[0010] Such seats are typically mounted on wheels that slide in
smooth tracks. This system constrains the movement of the seat to a
single dimension and reduces frictional losses.
[0011] For the purposes of teaching and high performance coaching
it is desirable to be able to measure the position of such a
sliding seat as it varies with time. From this data the velocity
and acceleration of the seat at any time can be derived. Such a
device should provide a single linear measurement from a known
point. This is sufficient to define the position of the seat in
space.
[0012] It would be undesirable for the device to alter the forces
required to move the seat since this would change the
characteristics of the rowing boat and alter the performance of the
athlete. This requirement rules out a lot of conventional contact
methods of determining position due to frictional forces.
[0013] An obvious solution to the need for a non-contact sensor
would appear to be an ultrasonic range finder. This however is not
a practical solution due to complications from spurious reflections
from the user's body.
[0014] A further problem is that if a sensor is to be mounted on
the sliding seat, a method of transmitting data from the sensor to
the boat or fixed structure of a rowing machine is required. Again
this must not interfere with the characteristics of the system.
[0015] A further problem is one of space and weight limitations.
Any sensor that is to be fitted to a sliding seat must be
lightweight in order not to interfere with the characteristics of
the system and is constrained on dimensions due to the geometry of
the seat and slide rail system.
BRIEF SUMMARY OF THE INVENTION
[0016] The object of this invention is to provide a device that
will accurately determine the position of a sliding seat as it
varies with time, without interacting with the mechanical
characteristics of the sliding seat system.
[0017] The invention uses an encoded strip which is attached to the
boat or rowing machine and a sensor arrangement which is attached
to the underside of the sliding seat. The sensor arrangement
includes a microcontroller that monitors the encoded pattern on the
strip and determines the position of the sliding seat. This data is
then transmitted via a radio link to the boat or fixed
structure.
[0018] The advantages of this system are that the seat position is
determined by a reliable non-contact method. The precision of the
measurement can be set by altering the geometry of the encoded
strip. The mass of the seat sensor arrangement is sufficiently low
to have negligible effect on the characteristics of the system. No
wires or other material interfaces are needed to retrieve the seat
position data from the sensor arrangement. The encoded strip can be
located as an integral part of the slide rails that support the
seat. This feature allows the system to be fitted to a boat or
rowing machine without encroaching on the space needed by the rower
or altering the geometry of the boat and seat in any significant
way.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0019] FIG. 1 shows a sliding seat and the invention in plan
view
[0020] FIG. 2 shows the detector and encoded strip in side view
[0021] FIG. 3 shows the detector as a functional block diagram
[0022] FIG. 4 shows an alternative arrangement in side view
DETAILED DESCRIPTION OF THE INVENTION
[0023] According to the present invention there is provided a
device for determining the position of a sliding seat
comprising,
[0024] One or more encoded strips attached to a boat or part of a
boat, one or more sensors attached to a sliding seat such that the
sensors detect the encoded strip and provide one or more channels
of encoded information, and a method a transmitting the output of
the sensor(s) from the seat to the boat or other location.
[0025] Preferably a detector is fixed to the seat comprising
sensors and supporting electronic circuits, a microcontroller, a
power source and a transmission method.
[0026] Preferably a receiver, designed to detect the signal
transmitted from the seat is fixed to the boat.
[0027] In other embodiments a receiver, designed to detect the
signal transmitted from the seat is fixed to another boat, shore
station or other location.
[0028] Encoded strips are attached to the boat, the rails that the
sliding seat runs in or a support bracket.
[0029] Encoded strips are mounted at any angle to the horizontal in
order to suit the design.
[0030] A single channel of digital encoded information may be used
to determine the speed of a sliding seat.
[0031] Two channels of digital encoded information may be used to
determine the speed and direction of movement of a sliding
seat.
[0032] Three channels of digital encoded information may be used to
determine the speed, direction of movement of a sliding seat and to
fix the position of the seat in absolute terms as it passes a given
point.
[0033] Multiple channels of digital encoded information may be used
to determine the absolute position of a sliding seat by providing a
unique output combination for each potential position of the
seat.
[0034] In one embodiment each channel of digital encoded
information is provided by a single sensor and single encoded
strip.
[0035] In another embodiment multiple channels of digital encoded
information are provided by multiple sensors and a single encoded
strip.
[0036] Preferably the encoded strip comprises sections with
properties that are good and poor infra-red reflectors and the
sensor comprises an infra-red source and detector.
[0037] In another embodiment the encoded strip comprises sections
of high and low magnetic field and the sensor is a hall effect
sensor.
[0038] Preferably the encoded strip and sensor are a non-contact
method of digital encoding.
[0039] In another embodiment one or more analogue strips, with
varying properties along the length of he strip are used to
determine the seat position.
[0040] Preferably the method of transmitting the sensor output from
the boat is a non-contact method.
[0041] Preferably the method of transmitting the sensor output from
the boat is a radio link, ultrasonic link or infra-red link.
[0042] In one embodiment raw data from the sensors is transmitted
from the seat.
[0043] In another embodiment the microcontroller analyses the
sensor output(s) and converts this information to a value
representative of the distance of the seat from a known point and
this value is transmitted from the seat.
[0044] A specific embodiment of the invention will now be described
by way of example with reference to the accompanying drawing.
[0045] Referring to the drawing a seat [3] has wheels [4] which run
on tracks [2] which are in turn attached to a boat [1].
[0046] A detector [5] is attached to the underside of the seat and
a receiver unit [6] is attached to the boat at a convenient
location. Three encoded strips [7,8,9] are fixed to the boat using
adhesive tape such that they are parallel to the direction of
motion of the seat and cover the full range of movement of the
seat. The encoded strips comprise a pattern of black and white
sections in which the black sections are a poor reflector of
infra-red radiation and the white sections are a good reflector of
infra-red radiation. The size of these sections is chosen to give
the required resolution. Three sensors [10,11,12] each comprise an
infra-red emitting diode and a phototransistor and are mounted on
the detector such that they are above the three encoded strips
[7,8,9] respectively.
[0047] Referring to FIG. 3, the three sensors are connected to a
processing circuit [13]. This circuit provides produces power to
the infra-red emitting diode and provides a low or high voltage
output depending on the state of the phototransistor. Thus three
output signals are obtained which correspond to whether each of the
three sensors is above a white or black section of the encoded
strip. A battery power source [15] provides power to the electrical
circuits.
[0048] A microcontroller [14] converts the three output signals
into a single value that is representative of the seat position.
From a single sensor output, the speed of the seat can be
determined. From a second sensor output, both speed and direction
can be determined. Encoded strips [8] and [9] are used to determine
speed and direction of the seat by relative encoding. FIG. 1 shows
that encoded strips [8] and [9] are alternate black and white
sections. Furthermore they are positioned longitudinally relative
to one another such that only one sensor output changes state at
any one time. This is done in order to prevent glitches. As the
seat moves over the encoded strip the output pattern from sensors
[8] and [9] will be as follows (low-low), (low-high), (high-high),
(high-low). The microcontroller detects changes in output state and
increments or decrements a parameter representative of the distance
of the seat from a known point. The third sensor represents the
state of encoder strip [7] and is used to fix the absolute position
of the seat. Encoder strip [7] is black except for a single section
of white at a known location. Thus every time the seat passes this
known point sensor [10] provides a high signal to the
microprocessor and the distance parameter is set to a value
representative of this position. The distance parameter is
transmitter from the seat to the boat via a radio link. The
microprocessor provides a pulse code modulated signal to a radio
transmitter [16] which is connected to an aerial [17]. The receiver
[6] (attached to the boat) detects the radio signal and converts
the pulse modulated signal back into the distance parameter.
[0049] In another example, three infra-red sensors [18,19,20] are
mounted on the seat in a line along the direction of travel of the
seat. A single digital encoded strip [21] of black and white
sections is fixed to the boat such that each of the three sensors
are over the encoded strip. FIG. 4 shows the arrangement. The
pattern of encoding is arranged such that at one seat position a
unique combination of the three sensor outputs is obtained [22].
This allows absolute location of the seat at this point. At all
other seat positions [23], two of the sensor outputs are used to
determine the relative movement of the seat, both in terms of speed
and direction. This arrangement has the advantage of reducing the
width of encoded strip required. This is useful since many boat
designs have limited space in this area.
[0050] In another example a single encoded strip is used in which
the infra-red reflective properties increase continuously along the
length of the strip. An infra-red transmitter emits a constant
level of radiation. A receiver on the seat measures the magnitude
of the reflected pulse thus determining the reflectivity of the
strip at that position. The measured reflectivity corresponds to a
unique seat position.
[0051] Whilst endeavoring in the foregoing specification to draw
attention to those features of the invention believed to be of
particular importance it should be understood that the Applicant
claims protection in respect of any patentable feature or
combination of features hereinbefore referred to and/or shown in
the drawings whether or not particular emphasis has been placed
thereon.
* * * * *