U.S. patent application number 14/207393 was filed with the patent office on 2014-11-13 for optically controlled motorized linear fader.
This patent application is currently assigned to QSC Audio Products, LLC. The applicant listed for this patent is QSC Audio Products, LLC. Invention is credited to Chuck T. Jensen, Greg C. Mackie, Peter F. Watts.
Application Number | 20140334079 14/207393 |
Document ID | / |
Family ID | 44257798 |
Filed Date | 2014-11-13 |
United States Patent
Application |
20140334079 |
Kind Code |
A1 |
Mackie; Greg C. ; et
al. |
November 13, 2014 |
OPTICALLY CONTROLLED MOTORIZED LINEAR FADER
Abstract
Methods and apparatus are provided for a control device and
control device operation. In one embodiment a control device
includes a slider configured to support a control knob, a rack
coupled to the slider and configured to linearly displace the
slider. The rack including slots. The control device may further
include a drive element configured to displace the rack and
position the control knob, and an optical detection module
configured to detect position of the control knob based on one or
more optical signals detected relative to slots of the rack.
According to another embodiment, a control console is provided
including control devices.
Inventors: |
Mackie; Greg C.; (Kirkland,
WA) ; Jensen; Chuck T.; (Everett, WA) ; Watts;
Peter F.; (Caramarthenshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QSC Audio Products, LLC |
Costa Mesa |
CA |
US |
|
|
Assignee: |
QSC Audio Products, LLC
Costa Mesa
CA
|
Family ID: |
44257798 |
Appl. No.: |
14/207393 |
Filed: |
March 12, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12987011 |
Jan 7, 2011 |
8680452 |
|
|
14207393 |
|
|
|
|
61294821 |
Jan 13, 2010 |
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Current U.S.
Class: |
361/679.01 ;
356/614 |
Current CPC
Class: |
H05K 7/00 20130101; G01D
5/264 20130101; H04H 60/04 20130101 |
Class at
Publication: |
361/679.01 ;
356/614 |
International
Class: |
G01D 5/26 20060101
G01D005/26; H05K 7/00 20060101 H05K007/00 |
Claims
1. A control device, comprising: a slider configured to support a
control knob; a rack coupled to the slider and configured to
linearly displace the slider, the rack comprising a plurality of
slots; a drive element configured to displace the rack and position
the control knob; and an optical detection module configured to
detect position of the control knob based on one or more optical
signals detected relative to slots of the rack.
2. The control device of claim 1, wherein the slider is supported
by at least one rod, and configured for linear displacement along
the at least one rod.
3. The control device of claim 1, wherein the control knob includes
a contact tab configured to detect user touch.
4. The control device of claim 1, wherein the control knob includes
a wiper configured to electrically couple the control knob to a
control circuit of the fader based on user contact with the control
knob.
5. The control device of claim 1, wherein slots of the rack are
equally sized and are employed by the optical detection module to
provide a linear encoder based on displacement of the rack.
6. The control device of claim 1, wherein the drive element is
coupled to a motor and relates to a drive wheel in contact with the
rack.
7. The control device of claim 1, further comprising a spring clip
configured to maintain the drive element in contact with the
rack.
8. The control device of claim 1, wherein drive element is
configured to control position of the control knob based on one or
more control signals received from a control unit.
9. The control device of claim 1, wherein optical detection module
includes at least one light source and at least two
photodetectors.
10. The control device of claim 1, wherein the optical detection
module includes a first circuit board configured to detect position
of the rack with phototransistors and a second circuit board
configured to provide a light source.
11. The control device of claim 10, wherein each circuit board is
arranged on an opposite side of the rack.
12. The control device of claim 1, wherein the optical detection
module includes a control unit configured to control and disable
operation of the drive element.
13. A control console comprising: a plurality of control devices; a
memory; and a processor coupled to the plurality of control devices
and memory, the processor configured to output one or more signals
to one or more of the control devices, wherein each control device
includes a slider configured to support a control knob; a rack
coupled to the slider and configured linearly displace the slider,
the rack comprising a plurality of slots; a drive element
configured to displace the rack and position the control knob; and
an optical detection module configured to detect position of the
control knob based on one or more optical signals detected relative
to slots of the rack.
14. The control console of claim 13, wherein the slider is
supported by at least one rod, and configured for linear
displacement along the at least one rod.
15. The control console of claim 13, wherein the control knob
includes a contact tab configured to detect user touch.
16. The control console of claim 13, wherein the control knob
includes a wiper configured to electrically couple the control knob
to a control circuit of the fader based on user contact with the
control knob.
17. The control console of claim 13, wherein slots of the rack are
equally sized and are employed by the optical detection module to
provide a linear encoder based on displacement of the rack.
18. The control console of claim 13, wherein the drive element is
coupled to a motor and relates to a drive wheel in contact with the
rack.
19. The control console of claim 13, wherein each control device
further comprises a spring clip configured to maintain the drive
element in contact with the rack.
20. The control console of claim 13, wherein drive element is
configured to control position of the control knob based on one or
more control signals received from the processor.
21. The control console of claim 13, wherein optical detection
module includes at least one light source and at least two
photodetectors.
22. The control console of claim 13, wherein the optical detection
module includes a first circuit board configured to detect position
of the rack with phototransistors and a second circuit board
configured to provide a light source.
23. The control console of claim 22, wherein each circuit board is
arranged on an opposite side of the rack.
24. The control console of claim 13, wherein the optical detection
module includes a control unit configured to control and disable
operation of the drive element.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application No. 61/294,821 filed Jan. 13, 2010, and entitled
"Optically Controlled Motorized Linear Fader," the disclosure of
which is hereby incorporated by reference in its entirety.
FIELD
[0002] The embodiments described herein relate generally to a
control devices and more particularly to an apparatus and method
for optical detection and control of a control device, such as a
fader.
BACKGROUND
[0003] Conventional audio mixing consoles typically employ a
plurality of slide controls, commonly referred to as faders, to
control the audio level of one or more signal channels. The
position of a control knob of the fader generally controls an
output, which is typically an electrical signal. Conventional
faders typically employ a carbon track to detect the position of
the control knob. A conventional mixer may employ faders which are
user controlled (e.g., non-motorized) or automatically controlled
(e.g., motorized faders). Motorized faders may be controlled by
providing an electric drive signal to a motor to adjust the
position of a control knob. Similar to non-motorized faders, these
faders may additionally be positioned by a user.
[0004] A drawback of conventional carbon track potentiometer faders
is the limited operating life of these faders due to contamination
of the carbon tracks. The carbon tracks may be contaminated by all
types of debris, such as dust, liquid, etc. Debris typically enters
through the control slot of the fader. As a result, mechanical
operating life of these conventional control devices may be greatly
reduced. Further, typical carbon track faders are rated as having a
lifespan of 10,000 cycles if the carbon track does not become
contaminated.
[0005] One attempted solution to avoiding contamination of carbon
track fader designs is to rotate the body of the fader so that dust
and/or other contaminating debris do not fall directly on a carbon
track. Another approach is to employ conductive plastic tracks
which may be more resilient to debris in comparison to carbon track
faders. However, these designs are either expensive, as in the
example of conductive plastic track designs, and/or can limit the
mechanical "feel" (e.g., stability, side-to-side wobble, etc.)
associated with the fader control knob. The feel and/or ease of
operation of a fader may directly define the overall quality of an
audio mixer to a buyer or user. Consumer success of audio consoles
may be based, at least in part, on perceived quality associated
with the mechanical feel of the faders. Accordingly, it is desired
to provide a fader with extended operating life that does not
diminish the "feel" of the fader over time and with use.
[0006] Another drawback of conventional faders relates to the
design of motorized drive systems. For example, micro drive belt
and tuner cord controlled devices used by conventional motorized
faders may limit the operating life of a fader. With use over time,
these drive mechanisms may fail and/or require maintenance.
[0007] Therefore, what is needed is an improved control device
design which overcomes one or more drawbacks of conventional fader
designs.
SUMMARY OF THE EMBODIMENTS
[0008] A method and apparatus for a control device are disclosed
and claimed herein. In one embodiment, a control device includes a
slider configured to support a control knob, and a rack coupled to
the slider, the rack comprising a plurality of slots and configured
linearly displace the slider. The control device further includes a
drive element configured to displace the rack and control position
of the control knob, and an optical detection module configured to
detect position of the control knob based on one or more optical
signals detected relative to slots of the rack.
[0009] According to another embodiment a control console is
provided including a plurality of control devices, a memory, and a
processor. The processor may be coupled to the plurality of control
devices and memory. The processor may be configured to output one
or more signals to one or more control devices. Each control device
includes a slider configured support a control knob, and a rack
coupled to the slider, the rack comprising a plurality of slots and
configured linearly displace the slider. Each control device
further includes a drive element configured to displace the rack
and control position of the control knob, and an optical detection
module configured to detect position of the control knob based on
one or more optical signals detected relative to slots of the
rack.
[0010] Further aspects, objects, desirable features, and advantages
of the apparatus and methods disclosed herein will be better
understood and apparent to one skilled in the relevant art in view
of the detailed description and drawings that follow, in which
various embodiments are illustrated by way of example. It is to be
expressly understood, however, that the drawings are for the
purpose of illustration only and are not intended as a definition
of the limits of the claimed embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1A depicts a control device according to one or more
embodiments;
[0012] FIG. 1B depicts a control device according to one or more
embodiments;
[0013] FIG. 1C depicts a disassembled view of the control device of
FIG. 1B according to one or more embodiments;
[0014] FIGS. 2A-2C depict graphical representations of chassis
guide members according to one or more embodiments;
[0015] FIGS. 3A-3C depict graphical representations of optical
position sensing according to one or more embodiments;
[0016] FIG. 4 depicts a simplified diagram of an optical detection
system according to one or more embodiments;
[0017] FIG. 5 depicts a simplified block diagram of a control
console employing a fader according to one or more embodiments;
[0018] FIG. 6 depicts a process for control of a fader according to
one or more embodiments;
[0019] FIG. 7 depicts a graphical representation of an control knob
according to one or more embodiments;
[0020] FIG. 8 depicts a graphical representation of optical
detection elements according to one or more embodiments;
[0021] FIG. 9 depicts a graphical representation of fader elements
according to one or more embodiments; and
[0022] FIG. 10 depicts a simplified block diagram of a fader
control unit according to one or more embodiments.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0023] One aspect of the embodiments described herein relates to a
control devices commonly referred to as faders, such as linear
controls or slide controls. In one embodiment, a control device is
provided to include one or more elements for optically sensing
positioning and displacement of a control knob associated with the
control device. The optical detection elements may be configured to
sense position of the control knob based on displacement of a rack
element relative to one or more optical detection elements. The
optical detection elements may allow for accurate and repeatable
detection of control knob position. As used herein, a control
device may be referred to as a fader. It should also be understood
that a control device as described in herein is not limited to
functioning as a fader. As such, output of a control device may not
be limited to a range of values from 0% to 100% based on control
device position.
[0024] In contrast to conventional fader and control devices,
control devices described herein may have operational use with no
mechanical wear or degradation and can easily exceed one million
cycles before failure. As such, the control devices described
herein can greatly exceed operation characteristics of conventional
fader devices. The control devices may include a drive system for
positioning a control knob. In one embodiment, a rack may position
a control knob of the control device based on wheel drive element,
such as a rubber wheel in contact with the rack. The control device
may include a slider configured to support a control knob, wherein
position of the slider may be detected based on displacement of the
rack. The control knob may include a contact tab configured to
detect user touch. The control device may be configured to initiate
and/or terminate the drive system based on user contact of the
contact tab to provide a touch sense of the control device. In
another embodiment, the control device may include a rack and
pinion drive system for motorized control of a control knob. The
drive system provided herein may provide a level of feel that is
improved relative to conventional fader designs.
[0025] In another embodiment, a control console is provided to
include a plurality of control devices. According to another aspect
of the embodiments described herein, a process may be provided for
detecting position of one or more control devices and controlling
one or more drive systems for controlling position of control knobs
singularly and in combination.
[0026] As used herein, the terms "a" or "an" shall mean one or more
than one. The term "plurality" shall mean two or more than two. The
term "another" is defined as a second or more. The terms
"including" and/or "having" are open ended (e.g. comprising).
Reference throughout this document to "one embodiment", "certain
embodiments", "an embodiment" or similar term means that a
particular feature, structure, or characteristic described in
connection with the embodiment is included in at least one
embodiment. Thus, the appearances of such phrases in various places
throughout this specification are not necessarily all referring to
the same embodiment. Furthermore, the particular features,
structures, or characteristics may be combined in any suitable
manner on one or more embodiments without limitation. The term "or"
as used herein is to be interpreted as inclusive or meaning any one
or any combination. Therefore, "A, B or C" means "any of the
following: A; B; C; A and B; A and C; B and C; A, B and C". An
exception to this definition will occur only when a combination of
elements, functions, steps or acts are in some way inherently
mutually exclusive.
[0027] In accordance with the practices of persons skilled in the
art of computer programming, embodiments are described below with
reference to operations that are performed by a computer system or
a like electronic system. Such operations are sometimes referred to
as being computer-executed. It will be appreciated that operations
that are symbolically represented include the manipulation by a
processor, such as a central processing unit, of electrical signals
representing data bits and the maintenance of data bits at memory
locations, such as in system memory, as well as other processing of
signals. The memory locations where data bits are maintained are
physical locations that have particular electrical, magnetic,
optical, or organic properties corresponding to the data bits.
[0028] When implemented in software, the elements of the embodiment
are essentially the code segments to perform the necessary tasks.
The code segments can be stored in a processor readable medium,
which may include any medium that can store or transfer
information. Examples of the processor readable mediums include an
electronic circuit, a semiconductor memory device, a read-only
memory (ROM), a flash memory or other non-volatile memory, a floppy
diskette, a CD-ROM, an optical disk, a hard disk, a fiber optic
medium, a radio frequency (RF) link, etc.
[0029] Referring now to the figures, FIGS. 1A-1C illustrate a
control device, referred to as a fader, according to one or more
embodiments. Referring first to FIG. 1A, a graphical representation
of fader 100 is depicted according to one embodiment. Fader 100 may
relate to an optically controlled linear control device according
to one or more embodiments. As depicted in FIG. 1A, fader 100
includes control knob 102 for user control. The position of control
knob 102 may correspond to a desired gain and/or level of a signal
controlled by fader 100. For example, position of the fader may
relate to values to provide a range associated with 0% to 100%
and/or different values. According to one embodiment, fader 100 may
be configured to optically detect the position of control knob 102.
Further, fader 100 may allow for user or motorized positioning of
control knob 102.
[0030] Control knob 102 may be supported by a metal tab (not shown
in FIG. 1 A) coupled to slider 104. Slider 104 may be configured to
linear displace control knob 102 along rods 106 and 108. In one
embodiment, slider 104 may be a plastic slider. Rods 106 and 108
may be comprised of steel or another conductive material. As shown,
rods 106 and 108 may be substantially parallel to allow for
positioning of slider 104. According to another embodiment, fader
100 may alternatively employ a C-chassis to allow for displacement
of slider 104 as discussed below with respect to FIGS. 2A-2C.
[0031] Control knob 102 of fader 100 may be configured to detect
user touch in order to provide touch sense. In one embodiment,
slider 104 may include a conductive wiper to provide conductivity
through rods 106 and 108 to circuit board 116. User activation, or
touch, of control knob 102 may be detected based on contact with a
contact tab of control knob 102 as will be discussed in more detail
below with respect to FIG. 7. In one embodiment, based on user
contact with control knob 102, the wiper may electrically couple
the contact tab to a control circuit of fader 100. One or more
signals provided by the conductive wiper of slider 104 may be
employed to provide touch sense. In that fashion, fader 100 can
detect user control of control knob 102 to adjust and/or cease
motorized operation of one or more faders. Touch sense of fader 100
may similarly allow for detection of a switch circuit (not shown)
that may be included in control knob 102 to detect user touch or
proximity to the knob according to another embodiment.
[0032] Slider 104 may be coupled to rack 110. Rack 110 may comprise
a plurality of slots and be configured to linear displace slider
104. Slots of rack 110 may be equally sized and employed with
phototransistors of the optical detection module to provide a
linear encoder based on displacement of the rack. Fader 100 may
additionally include a snap tab configured to support rack 110 to
drive element 112. As will be discussed in more detail below with
respect to FIG. 9, fader 100 may include spring 126 to provide
contact pressure between the drive system and rack 110.
[0033] Rack 110 may be positioned by a drive system comprising
drive element 112 and drive motor 120. Drive element 112 may be
configured to displace the rack and control position of control
knob 102. Drive element 112 may be coupled to motor 120 and relates
to a drive wheel as depicted in FIG. 1A in contact with rack 110.
Drive element 112 may also be configured to control position of
control knob 102 based on one or more control signals received from
a control unit. The drive system of FIG. 1A includes a rubber wheel
as drive element 112 coupled to motor 120 and configured to engage
rack 110. The bottom of rack 110 may be smooth to engage the rubber
wheel and/or other types of drive wheels. Additionally, the drive
system allows for user positioning of the control knob.
[0034] Fader 100 includes motor mount module 114 to support the
drive system and motor 120. As shown in FIG. 1A, motor mount module
114 may additionally support circuit board 116 and may be coupled
to slotted structure 122. According to one embodiment, motor mount
module 114 and slotted structure 122 may be configured to support
one or more components of fader 100. Support structure 128 may be
coupled to slotted structure 122 and may be configured to support
rods 106 and 108. Rods 106 and 108 may additionally be supported
by, and electrically insulated from, motor mount module 114.
[0035] According to one embodiment, fader 100 may include an
optical detection module to detect the position of control knob 102
and displacement of rack 110. The optical detection module may be
configured to detect the position of control knob 102 based on one
or more optical signals detected relative to slots of rack 110
depicted as 129. In particular, circuit board 116 and circuit board
124 may include one or more elements to optically detect
displacement of rack 110. Optical detection of fader movement
and/or linear displacement of rack 110 may be employed for
motorized control and control of one or more channels. In certain
embodiments control signals for positioning of control knob 102 may
be received by terminals 118 of circuit board 116. Similarly, a
detected position of control knob 102 may be output via terminals
118.
[0036] Optical detection of rack displacement may be based on light
detected relative to movement of one or more slots 129 of rack 110
relative to circuit boards 116 and 124. Slots 129 may relate to a
row of windows which may be used to optically detect the position
and/or displacement of rack 110. As will be discussed in more
detail below with respect to FIG. 8, circuit board 116 may include
one or more LED's and photodetectors (e.g., phototransistors) in a
directly-facing arrangement relative to each other. The optical
detection module may include at least one light source and at least
two photodetectors. In another embodiment, the optical detection
module includes first circuit board 116 configured to support a
light source for detecting position of rack 110 and second circuit
board 124 configured to support and receive one or more signals
from at least two light detection sensors. Circuit boards 116 and
124 may be arranged on opposite sides of rack 110 and configured to
electrically communicate.
[0037] Circuitry of fader 100 may be configured to detect
positioning of control knob 102 and/or user touch of contact tab of
control knob 102. The circuitry may be mounted to one or more of
circuit boards 116 and 124 and may include one or more components.
Terminals 118 may be coupled to a processor or controller of an
control device (e.g., control console, control module, audio
device, etc.) to output and/or receive one or more signals. The
circuitry of circuit boards 116 and 124 may additionally be
configured to output drive signals to motor 120. When a user
touches a control knob 102, the circuitry may temporarily disable
motorized control of rack 110. Based on user positioning of control
knob 102, fader circuitry may detect and/or store the position of
the control knob. Terminals 118 of circuit board 116 are depicted
as a plurality of conductive terminals according to one embodiment.
It should also be appreciated that terminals 118 can relate to
printed circuit board (PCB) edge card fingers.
[0038] Fader 100 may be configured to detect the position of
control knob 102. Circuitry of the fader may be configured to
detect position accuracy within increments of 0.5 mm according to
one embodiment. It should also be appreciated that smaller
increments of position accuracy may be employed. For example,
intermediate states where photodetectors are not completely on or
off can be measured to provide a higher resolution in between hard
on and off states. Similarly, by employing analog inputs, the
resolution may be increased to 0.25 mm, or even 0.125 mm in certain
embodiments.
[0039] Referring now to FIG. 1B, a graphical representation is
depicted of a fader according to another embodiment. Fader 130
relates to control device including gear rack 132 configured to
interface with pinion gear 134. Gear rack 132 may be positioned by
drive elements including pinion gear 134 and a drive motor (shown
as 144 in FIG. 1C). According to another embodiment, gear rack 132
may provide a row of windows which may be used to optically detect
the position of control knob 102 as will be discussed in more
detail below with respect to FIGS. 3A-3C.
[0040] Fader 130 may include snap tab 136 coupled to support gear
rack 132 to motor mount module 114. Fader 130 may additionally
include spring clip 138 to provide constant contact pressure
between pinion gear 134 and gear rack 132. Spring clip 138 relates
to a wire spring configured to snap to snap tab 136 in order to
provide proper contact pressure between pinion gear 134 and gear
rack 132. In that fashion, spring clip 138 may correct for possible
manufacturing inconsistencies for one or more components of fader
130 and increase the operational life of gear rack 132 and pinion
gear 134.
[0041] Fader 130 includes circuitry 117 configured to detect
positioning of control knob 102. Pins 140 of circuitry 117 may be
coupled to a processor or controller of an audio control device to
output and/or receive one or more signals. Circuitry 117 may
additionally be coupled to a drive motor of fader 130. Signals
received by pins 140 may control operation of the drive motor to
position gear rack 132.
[0042] Referring now to FIG. 1C, a semi-disassembled view is shown
of fader 130 of FIG. 1B. As shown in FIG. 1C, fader 130 includes
drive motor 144. As further shown, rods 106 and 108 may be
electrically coupled to circuitry 117 via wires 146a and 146b. Tab
150 is coupled to slider 104 and may be configured to support
control knob 102 (not shown in FIG. 1C). In that fashion, contact
of control knob 102 by a user may activate a conductive wiper of
slider 104 to provide conductivity through rods 106 and 108 to
circuit board 142 in order to provide a "touch sense." Touch sense
may relate to detecting user touch and modifying one or more signal
paths based on user operation of a control knob or control knob
during the user touch or contact. Touch sense may further allow for
disabling one or more drive elements associated with a control knob
during user contact of the control knob and optical detection of
the user positioning.
[0043] In one embodiment, circuitry 117 can include optical sensors
and/or optical infrared (IR) light emitting diodes (LEDs). Light
that is emitted from the LEDs may be directed through prism 143 to
be redirected through gear rack 132 to a sensor window with
openings above phototransistors. In certain embodiments, prism 143
may be coupled to circuit board 142 of circuitry 117. Light
directed through prism 143 may be redirected through windows, shown
as 148, of gear rack 132. In that fashion gear rack 132 may be
employed for optical detection of displacement and positioning of
control knob 102 and/or slider 104. The one or more windows
depicted as 148 may relate to a plurality of windows provided by
gear rack 135. Based on the position of gear rack 132, one or more
windows of the gear rack may straddle phototransistors of circuitry
117. Accordingly, the positioning of gear rack 132 may be
determined by sensing position using one or more pulses that may be
electrically translated by circuitry 118. According to another
embodiment, the position of gear rack 132 may be determined during
motorized operation and/or during user control of control knob
102.
[0044] Referring now to FIGS. 2A-2C, graphical representations of
chassis guide members are depicted according to one or more
embodiments. In certain embodiments, the faders of FIGS. 1A-C may
employ a chassis guide member instead of rods (e.g., rods 106 and
108) to guide positioning of a slider (e.g., slider 104). Referring
first to FIG. 2A, a C-chassis is depicted according to one
embodiment. C-chassis 200 may be employed by a fader to allow for
positioning of a slider within C-chassis 200 as shown by 205.
C-chassis 200 may be comprised of steel or another conductive
material. A conductive wiper of the slider may conduct through
C-chassis 200 to a circuit board of the fader to provide touch
sense signals in certain embodiments.
[0045] Referring now to FIG. 2B, a C-chassis is depicted according
to another embodiment. Round C-chassis 250 relates to a guide
member with a curved shape to allow for positioning of a slider as
shown by direction 255. In FIG. 2C, slider 260 and round C-chassis
250 are shown according to another embodiment. Slider 260 (e.g.,
slider 104) may be a plastic slider including wiper 265 to provide
touch sense as described herein.
[0046] Referring now to FIGS. 3A-3C, graphical representations are
depicted of optical position sensing according to one or more
embodiments. Referring first to FIG. 3A, a disassembled view is
depicted of elements of optical sensor 300. According to one
embodiment, optical sensor 300 includes phototransistors 305a-305b,
sensor window 310 and slide rail encoder 320. Slide rail encoder
320 may be attached to, or part of, a rack (e.g., rack 110, gear
rack 132). Optical sensor 300 may be configured to detect light
emitted from LEDs associated with displacement of a fader control
knob (e.g., control knob 102).
[0047] In one embodiment, light emitted from the LEDs may be
directed from a prism through windows of a gear rack (e.g., gear
rack 125). As will be discussed in more detail below with respect
to FIG. 10, two circuit boards may be employed instead of a prism
to optically detect rack displacement and position. In one
embodiment, optical sensor 300 includes two phototransistors
305a-305b to detect the LED light redirected through a rack. It
should also be appreciated that additional phototransistors may be
employed in certain embodiments.
[0048] Phototransistors 305a-305b may be configured to detect LED
light received via one or more openings, shown as 350, of slide
rail encoder 320. Phototransistors 305a-305b may be included in
circuitry of the fader. Slide rail encoder 320 may overlay
phototransistors 305a-305b to provide a path for LED light from
circuit board 310 including light source 315. Based on positioning
of a control knob of a fader, slide rail encoder 320 may be
displaced with respect to circuit board 310. Phototransistors
305a-305b may be configured to detect displacement based on light
received via windows 325 of slide rail encoder 320. Optical
position detection will be discussed in more detail below with
respect to FIG. 3C. Slide rail encoder 320 may relate to windows of
a rack and may straddle phototransistors 305a-305b.
[0049] Referring now to FIG. 3B, a graphical representation is
shown of the slide rail encoder 350 of the optical sensor
overlaying the light source. The optical sensor may detect light
received via windows in slide rail encoder 350 and sensor window
310, shown as 355. As such, optical position sensor 350 can detect
light directed by a prism, or circuit board, for a minimum
footprint shown as 360. In that fashion, the optical sensor may
detect the positioning of the gear rack using one or more pulses
that may be electrically translated by circuitry during motorized
operation and/or during user control.
[0050] Referring now to FIG. 3C, a graphical representation is
depicted of operation of the optical sensor of FIG. 3A. Graphical
representations 370 depict four states in which light passes
through windows or slots of a rack to phototransistors of the
optical sensor. The optical sensor states, associated with
positions shown as 371-375, allow for detection of rack
displacement (and control knob position) in each direction. Each
position of the fader may be associated with one of the states.
Slide rail encoder 320 of optical sensor 300 includes a plurality
of windows 325 for light emitted by LED 380 to pass. Based on the
position of slide rail encoder 320, phototransistors 381a-381b
(e.g., phototransistors 305a-305b) may or may not detect the LED
light. In one embodiment, LED 380 may relate to a single LED. In
other embodiments, LED 380 may relate to a plurality of LEDs, such
as LED pair of FIG. 8.
[0051] States 371 and 375 may relate to states of the control knob
wherein LED light can be detected by each of the phototransistors
381a-381b. As the rack is displaced, shown by direction 385 with
respect to LED 380 and phototransistors 381a-381b, windows 325 may
block one or more of the phototransistors 381a-381b. For example,
in position 372 phototransistor 381a is blocked, while
phototransistor 381b may receive light emitted by LED 380 due to
the position of slide rail 320. State 373 depicts blockage of each
phototransistor. State 374 depicts detection by phototransistor
381a and blockage of phototransistor 381b as the rack is
subsequently displaced in direction 385. Output of each of
phototransistors 381a-381b may be detected and monitored by
circuitry of the fader (e.g., circuitry 118) to determine position
of the control knob. Further, a current position of the control
knob may be stored in memory by one or more of a mixer and control
console. Stored position may be used to determine subsequent
positioning by a user and/or motorized positioning.
[0052] Referring now to FIG. 4, a simplified diagram is depicted of
an optical detection system according to one embodiment. Optical
detection system 400 includes circuit board 405 which includes
phototransistors 410 (e.g., phototransistors 305a-305b) and light
blocker 415 (e.g., sensor window 310). Circuit board 405 may
additionally include light source 420 (e.g., LED 380) configured to
emit light, shown as 435, via prism 425 of coupler 430 (e.g.,
coupler 160). As depicted in FIG. 4, prism 425 is configured to
direct light 435 to phototransistors 410 based on the position of
rack 445. Openings of rack 445, shown as 440, can allow light to be
detected by phototransistors 410. As will be discussed below with
reference to FIG. 8, an optical detection system may employ an
additional circuit board to detect light emitted by circuit board
405.
[0053] Referring now to FIG. 5, a simplified block diagram is
depicted of a control console which employs a fader according to
one or more embodiments. Control console 500 may relate to an audio
control device (e.g., a mixer). It should also be appreciated that
control console 500 may relate to any type of control device which
employs a fader or linear control device in general. As shown,
control console 500 can include one or more faders 505.sub.1-n to
control gain or input level of one or more signals received on
input terminals 510.sub.1-n. Processor 515 may be configured to
process one or more audio signals received by input terminals
510.sub.1-n based on the position of control knobs and/or sliders
of faders 505.sub.1-n. According to one embodiment, each of faders
505.sub.1-n may be configured to optically detect the position of a
control knob and further may be configured to adjust the position
of a control knob based on one or more signals received by
processor 515.
[0054] According to another embodiment, data processed by processor
515 related to input data received by input terminals 510.sub.1-n
and/or data associated with positioning of faders 505.sub.1-n may
be output by output interface 525. It may also be appreciated that
display 520 may be configured to display data based on data
received and/or position of faders 505.sub.1-n. According to
another embodiment, display 520 may be configured to display the
position and/or user inputs for control of faders 505.sub.1-n.
[0055] Faders 505.sub.1-n may each be configured to provide touch
sense. For example, each fader may be configured to include a touch
sensitive contact tab. In contrast to conventional consoles, touch
sense as used herein may be based on user touch of metal tabs or
sensor of the control knob of the fader. As shown in FIG. 5,
contact tabs 506.sub.1-n relate to exposed metal tabs at which may
be positioned on each fader control knob. Contact tabs 506.sub.1-n
may be coupled to circuitry of the fader via a wire and/or
coupling. Based on user touch of a fader, specifically a contact
tab, control console 500 may be configured to perform one or more
functions. In one embodiment, contact tabs 506.sub.1-n may be
located at the center of the fader control knob.
[0056] According to one embodiment, the control console 500 may
display one or more of a channel number, bank select (e.g.,
selection of a plurality of faders) and name (if given a name) on
display 520 based on user touch of a contact tab. For example, if
the channel was named "lead guitar," display 520 would display lead
guitar, the channel number and associated bank information. In that
fashion, control console 500 may provide automatic identification
of the name, title, or use of a particular fader within a channel
of the console. The identification may provide the functionality of
an electronic write strip for the fader. For effects channels (such
as FX return), selected effects may be indicated by display 520
when a fader tab is touched. Alternatively, if no effects have been
selected or associated with a fader, display 520 may output a
display message such as "no fx." Further, when multiple fader tabs
are touched, display 520 may be configured to not display
attributes such as name, title or effects associated with the
tabs.
[0057] Control console 500 may be configured to allow for selection
and/or control of one or more faders. Faders group button 535 may
be employed by users for selection of a group of faders. For
example, a user may select faders group button 535 which may be
configured to blink based on a user selection. The user may then
select one or more of faders 510.sub.1-n by selecting a button, or
touching a contact tab of a control knob, for each fader to be
selected. Based on user selection, each selected button, or an LED
associated with the fader, may be configured to blink. A user may
then select faders group button 535, at which time each button will
stop blinking. To adjust faders within a group, a user can touch
the tab, such as tab 506.sub.1, and move the fader. As such,
control console 500 may be configured to adjust each fader
associated with the fader group.
[0058] According to another embodiment, to adjust only a single
fader of a group, a user can adjust the fader without touching the
control knob. Control console 500 may additionally be configured to
detect simultaneous movement of more than one fader in a group when
a user tries to move more than one fader. In some instances control
console 500 may suspend group adjustment. According to another
embodiment, control console 500 may be configured to provide a
reverse audio function wherein all faders may be decreased when a
single fader control knob is increased.
[0059] Control console 500 may be configured to allow a user to
name each fader based on manufacturer supplied names and/or user
defined names. In one embodiment, a factory name may be selected by
a user touching a fader tab, such as tab 506.sub.1, and rotating
master control encoder 530 to select a stored name. Display 520 may
be configured to list factory stored names. A user may then depress
master control encoder 530 to select a displayed name. To select a
custom name, a user may employ master control encoder 530 to select
one or more characters (e.g., alphanumeric) to define a name for
one or more faders. In certain embodiments, control console 500 may
include an interface for coupling to a keyboard or input device. In
that fashion, a user may specify one or more custom names using the
keyboard. Control console 500 may additionally store a list of
names previously used.
[0060] According to another embodiment, control console 500 may be
configured to provide a faders down function. By selecting faders
down button 540, control console 500 may be configured to position
the faders within a single control bank to the lowest position
(e.g., an "Off" position). This eliminates the need for the
operator to manually move all faders to the lowest position. Faders
down button 540 may avoid possible damage to fader controls by
users who simultaneously position each of faders 510.sub.1-n. In
certain embodiments, faders down button 540 may be triggered after
a user presses faders down button 540 for at least a predetermined
period of time (e.g., 1-2 seconds) in order to reduce unwanted
triggering. Faders down button 540 may relate to one of a hard
button and soft button. Control console 500 may employ
functionality associated with faders down button 540 to calibrate
the position of a control knob.
[0061] According to another embodiment, control console 500 may
include one or more indicators to aid in adjustment of faders. In
certain embodiments, control console 500 may employ non-motorized
faders. Accordingly, control console 500 may optionally include an
indicator 545 for one or more faders. Indicator 545 may be employed
by a user to set a fader control knob to match a scene setting of
the console. For example, scene setting may relate to one or more
predefined positions for each fader. As such, control console 500
may illuminate one or more LEDs of indicator 545 to assist a user
to position a fader. Indicator 550 may indicate that a fader should
be lowered, indicator 555 may indicate a correct position and
indicator 560 may indicate that the fader should be raised. Console
500 may include indicators 550, 555, and 560 for each fader.
[0062] Although use of faders has been described in connection with
an audio console in FIG. 5, it should also be appreciated that a
fader as described herein may additionally be employed for other
equipment. For example, control console 500 may be configured for
operation as one or more of a lighting console, audio effects
parameter control, audio/video console, controllers for remote
positioning/movement of servo controlled equipment, and any device
in general which requires one or more positioning controls.
[0063] Referring now to FIG. 6 a process is depicted which may be
performed by circuitry of the fader of FIGS. 1A-1C according to one
embodiment. Process 600 may be initiated by optically detecting
position of a fader (e.g., fader 100) at block 605. For example, in
one embodiment optical sensors of the fader circuitry may be
configured to detect light emitted from LEDs directed through a
rack of the fader. Based on the position of rack, the position of a
control knob of the fader may be detected at block 605. Position of
the rack may be determined at block 605 while the control knob of
the fader is under motorized control, user control and/or while
stationary.
[0064] At block 610, circuitry of the fader can monitor control
signals for motorized operation. Control signals may be received
from a controller (e.g., processor 515) of a control console (e.g.,
console 500) to control movement of the fader. Alternatively, or in
combination, one or more signals generated by the fader, such as
user touch of the fader, may be monitored at block 610. Based on
one or more signals received at block 610, fader circuitry can
determine whether to position a control knob of the fader at
decision block 615. When the control knob does not require
positioning (e.g., "NO" path out of decision block 615), the fader
circuitry may continue to monitor control signals at block 610.
When the fader circuitry determines that positioning of the control
knob is required (e.g., "YES" path out of decision block 615), the
circuitry may output one or more control signals to operate a motor
(e.g., drive motor 150) to control fader position at block 620.
Process 600 may proceed to adjust signal gain of one or more
signals received based on the position of the fader control knob at
block 625 before returning to block 605.
[0065] Referring now to FIG. 7, a graphical representation is
depicted of a control knob according to one or more embodiments.
Control knob 700 may be employed by one or more of the faders
described herein. Control knob 700 includes contact tab 705.
Contact tab 705 may relate to a metal tab enclosed by control knob
700 and electrically coupled to a slider (e.g., slider 104) or
circuit board (e.g., circuit board 116). Based on user contact with
contact tab 705, circuitry of the fader may detect a user touch.
Based on the user touch, the circuitry of the fader may cease
motorized control of control knob 700. In certain embodiments,
contact tab 705 may relate to a sensor configured to detect a users
touch or close proximity to control knob 700. For example, contact
tab 705 may relate to one or a capacitive and optical sensor.
Control knob 700 further include indicia 710 which may be used to
align the control knob with indicia of a control console (e.g.,
console 500). Indicia 710 may relate to a separately colored
portion of the control knob or a marking in general.
[0066] Referring now to FIG. 8, a graphical representation is
depicted of optical detection elements of a fader according to one
or more embodiments. FIG. 8 depicts a dissembled view of one or
more elements of the fader of FIG. 1A. In one embodiment, optical
detection elements 800 may be employed to detect the position or
displacement of a rack (e.g., rack 110) employing the optical
detection process discussed above with respect to FIGS. 3A-3C.
Optical detection elements 800 include circuit board 805 (e.g.
circuit board 116) and circuit board 840. Circuit board 805
includes solder pads 815 which may interface with phototransistors
820. Circuit board 805 additionally includes terminals 810 which
may be configured to output one or more signals based on output of
phototransistors 820. Light guide 825 may be configured to support
circuit board 840 relative to circuit board 805. Light guide 825
may be comprised of an opaque plastic material and may be
configured to allow light from LEDs 835 to pass through one or more
slots of a rack (e.g., rack 110) for detection by phototransistors
820. Accordingly, light guide 825 includes a slot to allow a rack
to freely move between. Light guide 825 may additionally include
conductor pins 830 which may be employed to provide power for the
LEDs.
[0067] Circuit board 840 may include slots 845 for receiving
conductor pins 830. LEDs 835 may be configured to output light
based on one or more output signals by circuit board 840. In one
embodiment, circuit board 840 may be electrically coupled to
circuit board 805 via conductor pins 830. It should also be
appreciated that optical detection elements 820 may be employed for
one or more embodiments of control devices described herein.
[0068] Referring now to FIG. 9, a partially disassembled view is
depicted of a fader according to one or more embodiments. As
depicted in FIG. 9, rack 905 (e.g., rack 110) is depicted relative
to circuit board 910 (e.g., circuit board 805). Circuit board 910
may be configured to support phototransistors depicted as 915
according to one embodiment. Phototransistors 915 may be configured
to detect light emitted from a second circuit board (e.g., circuit
board 840, not shown in FIG. 9) relative to slots 920 of rack
905.
[0069] According to one embodiment, tab 925 may be configured for
coupling to circuit board 910, or alternatively to a housing of the
control device, as a guide for rack 905. One advantageous element
of the control device may be spring clip 930 which may be
configured to maintain contact of rack 905 to a drive element
(e.g., drive element 112). Spring clip 930 (e.g., spring clip 138)
may be positioned above tab 925 and within channel 935. In that
fashion, an inexpensive solution may be provided for maintaining
contact of rack 905 with a drive element and providing needed, but
controlled, friction. In addition, spring clip 930 may be
configured to apply pressure to rack 905 to allow the rack to
easily slide when displaced by a drive element and when displaced
due to user positioning of a control knob. Spring clip 930 may
relate to a wire spring and may correct for possible manufacturing
inconsistencies of one or more components of a control device.
Another advantage of spring clip 930 may be an increase in
operational life of rack 905 and a drive element.
[0070] Referring now to FIG. 10, a simplified block diagram of a
fader control unit is depicted according to one or more
embodiments. In certain embodiments, a fader (e.g., fader 100 or
fader 130) may be configured to receive one or more signals for
controlling operation and positioning of a control knob. Received
control signals by the fader may activate a drive element or motor
of the fader. In other embodiments, a fader may include a control
module as depicted in FIG. 10. Control module 1000 may be
configured to receive one or more control signals from a controller
of a console and transmit one or more signals to the controller. In
certain embodiments, control module 1000 may be configured to
translate one or more received control signals for activating
and/or disabling drive elements, and determining position of a
control knob.
[0071] As depicted in FIG. 10, control module 1000 includes control
unit 1005, memory 1010, optical sensor unit 1015, drive interface
1020 and input/output (I/O) interface 1025. Control unit 1005 may
be configured to receive and transmit one or more control signals
to a processor (e.g., processor 515) of a control board. Operation
of control unit 1005 may be based on one or more instructions
stored by memory 1010. Optical sensor unit 1015 may relate to one
or more elements for optically detecting displacement of a rack
(e.g., rack 110) of a control device. Based on one or more signals
received from optical sensor unit 1015, control unit 1005 may
generate one or more signals to activate or deactivate drive
interface 1020. In one embodiment, control unit 1005 may be
configured to decode one or more signals detected by optical sensor
unit 1015 employing the decoding processes described above with
reference to FIGS. 3A-3C. In certain embodiments, control unit 1005
may be configured to determine a base line position or calibrate a
position of a control knob during initialization of the fader.
Further, during displacement do to user and/or control device drive
elements, control unit 1005 may determine a position of the control
knob.
[0072] Drive interface 1020 may be coupled to a drive element, such
as a motor, for positioning a control knob and displacing a rack.
I/O interface 1025 may include one or more terminals (e.g.,
terminals 745) for receiving and/or transmitting control signals to
an external control module.
[0073] Although the embodiments has been described with reference
to preferred embodiments and specific examples, it will be readily
appreciated by those skilled in the art that many modifications and
adaptations of the motorized linear fader described herein are
possible without departure from the spirit and scope of the
embodiments as claimed hereinafter. Thus, it is to be clearly
understood that this description is made only by way of example and
not as a limitation on the scope of the embodiments as claimed
below.
* * * * *