US20110212757A1 - Smart capacitive detection sensor system - Google Patents

Abstract

An apparatus that wirelessly integrates actual golf equipment with a computer to allow players to engage in a competitive real sport such as golf. This system includes motion sensing devices, smart golf clubs, and golf ball receptacles all containing circuits and contact sensors coupled with signal processing and radio frequency transmitter circuitry to thereby wirelessly communicate game performance information to a remote receiver-computer. This invention uses the electric field of a capacitive plate for sensing object proximity, motion and composition. More particularly, the invention relates to a system wherein an objects physical geometry, spatial orientation and motion, and an environmental change of state can be detected via a change in the dielectric of a capacitor array. This invention also uses the coupling of sports equipment and a computer to communicate information wirelessly to a personal computer and thereby, if desired, to the internet. An individual player may opt to play solo or practice to improve basic golfing techniques. The system employs specially developed computer software to process player performance data, control game play, communicate game information, generate and control visual simulations, and display player performance information.

Description

CROSS REFERENCE TO RELATED APPLICATION
• Priority is claimed from U.S. Provisional Ser. No. 60/13,722, filed May 12, 1999 for all subject matter common hereto. That provisional application is incorporated by reference herein. This is a divisional application and the parent application for this divisional application is, Ser. No. 09/570,233.
REFERENCE TO MICROFICHE APPENDIX
• A microfiche appendix including 1 microfiche with 27 frames accompanies and forms a part of this application.
FIELD OF INVENTION
• This invention uses the electric field of a capacitive plate for sensing object proximity, motion and composition. More particularly, the invention relates to a system wherein an objects physical geometry, spatial orientation and motion, and an environmental change of state can be detected via a change in the dielectric of a capacitor array. This invention also uses the coupling of sports equipment and a computer to communicate information wirelessly to a personal computer and thereby, if desired, to the internet.
BACKGROUND OF THE INVENTION
• Resolving an object's direction post impact is a problem that has been addressed in the literature often with great complexity. In addition, few high-tech solutions have been employed but may be unsuitable for use under repeated impact of the object and impact surface.
• A number of patented devices embody various object sensor contacts or implement swing sensing components. Typically, these devices display information related to a player's swing and accuracy in hitting a golf ball. In certain of these, the information is displayed and signaled by the golf club itself in the form of a small visual readout or an audible sound. One such device contains an array of mechanically depressible pins on the face of the golf club. When the ball is struck by the club, the pins are physically depressed in a pattern to inform the player of the location on the club face where contact with the ball occurred, however, it does fails to predict the ball's subsequent trajectory. Another device uses a light emission and reflection detection technique to provide information to a player, displayed on the club, regarding the alignment of the golf ball with the preferred location on the golf club face.
• Also, numerous conventional computer golf game software packages and video games use a variety of unrealistic techniques to emulate the striking of a golf ball with a club. None of these cooperates with actual golf clubs, actual golf ball target or cup receptacles, or a swing detector that senses the actual golf stroke.
• It is desirable to obtain some insight into directionality of an object resulting from the impact of a golf club or sports implement and to remotely communicate actual player performance location, whereby more sophisticated analysis and prediction possibilities are realizable via computer technology and state-of-the-art display techniques. Further, it is also desirable to use such performance information in an expanded capacity to provide interactive competitive play among numerous players in locations remote from each other.
• It is also desirable to sense and discern proximal object shape factors, environmental changes, material composition, ambient conditions and perturbations.
SUMMARY OF INVENTION
• This invention relates to a system that interconnects a golf club or other sports implements to a computer. In a preferred embodiment the computer is coupled wirelessly to a capacitive plate, a receptacle or a swing sensing component. A single player may play without an opponent to practice and improve basic sports skills using a computer and display to track their performance. Further, the invention, with components summarized below, uses the electric field of a capacitive plate array for sensing object proximity, motion and composition. More particularly, the invention relates to a system wherein an objects physical geometry, spatial orientation and motion, and an environmental change of state can be detected via a change in the dielectric of each capacitor in the array.
• The system application is unlimited. Much of this system can be used not only for golf competition locally and remotely via the Internet, but for other sports and applications as well. Sports implements other than golf clubs can be used with this invention to determine proximity, spatial orientation, directionality, geometry, and material composition. This invention can be used for training purposes, rehab, or for interactive internet competition.
• The technology can be used for training, competition, and the improvement of player reflexes and coordination. With little or no modification, the technology also has applications in medicine, particularly physical therapy.
1. Smart Golf Club
• A wireless golf club is constructed to contain or alternatively, a standard golf club is modified to contain, a multiple sensor or transducer array located on the club head at the face or hitting surface. Upon impact of the head of the club with a golf ball, the impacted sensors produce detectable variances representing the magnitude and duration of the club-ball impact force and the proximate location of such contact relative to the preferred location, the “sweet spot”, on the face of the club head. The variances are electronically processed into digitally coded information and remotely transmitted by an electrical communication circuit either contained within or attached to the golf club.
• In each golf club device and golf ball receptacle device according to this invention, in a preferred embodiment the transducers are or include piezoactive elements and or pressure sensors. As used herein, “piezoactive” includes piezoelectric and piezoresistive components. Piezoactive components are defined as components the electrical properties of which, when the component is subjected to physical force, vary.
• The smart golf club system uses biofeedback to create an intelligent golf training and entertainment system. The smart golf club system is a diagnostic and analysis tool used to improve a player's skills by relatively instantaneous visual cues and acoustic feedback with little or no human intervention. The smart golf club system takes the generated data and reconstructs it into a useful visual format that can be presented in a variety of ways including 3-dimensional animation. The smart golf club system integrated circuit or circuits can be located anywhere within the club including the head and or shaft.
• The smart golf club has a means via its built in microcontroller to process, analyze, store, hitting pattern data and transmit it to the computer and or the Internet for further analysis. In playback mode the smart golf club system memorizes how many times each sensor was hit. This provides the golfer information about his or her hitting pattern. Using a computer algorithm, we can analyze and calculate a hitting pattern and having a personalized sports hitting detection system for each athlete.
2. Golf Ball Receptacle
• A ball receptacle has an open end to receive a golf ball and contains a transducer located so as to sense the ball entering receptacle. Upon impact with the golf ball, the sensor produces a detectable variance representing impact with the ball. The variance is electronically processed into display coded information and remotely transmitted by an electrical communication circuit. In one preferred embodiment the communication circuit is contained within the receptacle. Preferably the communicate circuit for the receptacle is a radio frequency transmitter. The receptacle can either be designed for indoor use or can be a cup in an actual green with the communication circuit housed in the cup or elsewhere.
• In each of the golf club device and golf ball receptacle device according to this invention, in a preferred embodiment the transducers are or include piezoactive elements. As used herein, “piezoactive” includes piezoelectric and piezoresistive components. Piezoactive components are defined as components the electrical properties of which, when the component is subjected to physical force, vary.
3. Golf Club Motion Sensor Plate
• A golf club swing motion sensing device contains an array of uniformly distributed sensing transducers upon or proximate to the device surface. This motion sensing device may be formed as a mat or a plate or other substantially flat surface from which a golf ball is hit. The transducers produce detectable varying characteristics such as capacitance representing the velocity, angle, and proximity of a golf club relative to the surface of the device. The variances are electronically processed into digitally coded information and remotely transmitted by an electrical communication circuit contained within or electronically connected to the device.
4. Wireless Signal Receiver and Computer
• At each remote player site, wireless radio frequency equipment receives the digitally coded transmitted signals from the golf club, the golf ball receptacle, and the club swing motion sensing device. The signals are demodulated and processed into serial binary data suitable for communications to the computer via either serial or parallel ports. As the game progresses, the computer under the control of the golfing software, monitors and directs the flow of communications between the players via the internet and displays the game simulations and performance information.
5. Computer Golfing Software System
• At each remote player site, a computer under the control of the golfing software, monitors and controls the sequential play of the game and interacts with the player at the site and also competing players at the other remote sites via the internet. The software system generates the game simulations for display and tracks each player's performance as the game progresses.
• The above and further features and advantages of the invention will be better understood with reference to the accompanying drawings and the following detailed description of preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a diagrammatic illustration of components of a computer implemented golf system according to this invention.
• FIG. 2 is a top plan view of a golf club with sensors and circuitry and used in the computer implemented system ofFIG. 1.
• FIG. 3 is front elevation view of the golf club head ofFIG. 2, and shows three sensors located at the face of the club head.
• FIG. 3 A is a front plan view of a further embodiment of a club head for use with the computer implemented golf system ofFIG. 1.
• FIG. 4 is a diagrammatic front plan view of a putter with a club head and circuitry forming a further, alternative embodiment of a club for use with the computer implemented system ofFIG. 1.
• FIG. 5 is a schematic block diagram of a club head electronics installation for use with the club heads ofFIGS. 2-4.
• FIG. 6A is a front elevation view of a golf ball receptacle for use with the system ofFIG. 1.
• FIG. 6B is a cross-sectional view along the lines B-B ofFIG. 6A.
• FIG. 6C is a fragmentary top plan view of the receptacle ofFIGS. 6A and 6B illustrating internal components of the receptacle.
• FIG. 7 is a top plan view of a golf ball sensing element with three distinct activation areas for use in the receptacle ofFIGS. 6A-6C.
• FIG. 8 is a schematic block diagram of a receptacle electronics installation for communicating with the computer in a computer implemented system according toFIG. 1.
• FIGS. 9A-9D are diagrammatic illustrations of a golf club motion or swing sensor plate for use with the system according toFIG. 1.
• FIG. 9E is a block diagram of electronics used in association with the swing sensors plate ofFIGS. 9A-9D.
• FIG. 10 is a block diagram of a computer installation for use as the computer and information receiving interconnect of the system ofFIG. 1.
• FIG. 11 is a functional block diagram of the software operation of the computer ofFIG. 10.
• FIG. 12 is a flowchart illustrative of a portion of the operation of the computer ofFIG. 10 operating as indicated in the block diagram ofFIG. 11.
DETAILED DESCRIPTION OFPREFERRED EMBODIMENT1. Smart Golf Club
• Thesmart golf club20 has ahead40 and ashaft42. As shown inFIGS. 2 and 3, thehead40 has ashaft opening42, a plurality of embedded contact sensors46 (three are illustrated in the preferred embodiment), and theinternal electronics circuitry48 including a wireless radio frequency transmitter (58 inFIG. 5). As shown, at least one of thesensors46 is located at or proximate to the optimal location on a club face47 for contact with the golf ball, the “sweet spot”49. The remaining two sensors are adjacent and on either side of thesweet spot49. The contact sensors may be, but are not limited to sensors employing piezoactive type transducers, specifically, either piezo-electric or piezo-resistive transducers (similar, but is not limited to the Cooper Instruments LPM 562).
• In an alternative embodiment,FIG. 3A, threesensors46 are applied to the face of an adapted club by a Mylar tape orother means49. Again, the electronic circuitry is internal to theclub head40 and connects to thesensors46 by leads27.
• In a second alternative embodiment, to retrofit a standard golf club,contact sensors46 are part of anadapter40 attached to an ordinary club head as seen inFIG. 4 and wire connected to anelectronic circuitry48 attached to theclub shaft42 or elsewhere on the club.
• A golf ball contacting anysensor46 produces a detectable variance indication the magnitude and duration of sensor-ball impact. The variance may be a change in resistance of a piezo-resistive transducer or a voltage change in the case of a piezo-electric transducer. As shown inFIG. 5, the variance is detected and amplified by an associatedamplifier52 and is the input to an associatedintegration circuit54, the output of which represents the energy of the ball-club contact event. Connected to theintegration circuit54, amicroprocessor56 is a multi-input signal processing circuit (similar, but not limited to a Motorola #68HCO5) having analog to digital signal converting circuits (ADCs), one for each input channel, and a sequential digital signal encoding circuit connected so as to convert the ADC outputs into a time multiplexed serial digital data stream containing a binary-coded word for each channel indicating the energy of the associated sensor-ball impact event.
• A radiofrequency transmitting circuit58 receives the serial digital data from themicroprocessor56 and wirelessly transmits the information via an internal antenna60 to a receiver26 (FIG. 1) for subsequent processing by thecomputer28.
2. Golf Ball Receptacle
• Thegolf ball receptacle22 has a top62 shaped to allow entry of a golf ball, as shown inFIGS. 6A,6B, and6C. The receptacle has acontact sensor pad64, shown inFIG. 7, containing at least one contact sensor (threedifferent activation areas65,66, and67 are illustrated in the preferred embodiment), a ball return mechanism69 (FIG. 6B) and internal electronic circuitry68 (FIG. 6B). The internal circuitry includes a wireless radio frequency transmitter (not separately shown inFIGS. 6A, B and C). As shown, the preferred embodiment hascontact sensor pad64 positioned within the receptacle60 such that thecenter activation area66 aligns with the center of aball entry70. Additionalsensor activation area65 and67 are adjacent, one on either side of thecenter area66. In the preferred embodiment, ofFIGS. 6A,6B, and6C, and like the sensor used at the face of the club, the sensors may be, but are not limited to, sensors employing piezo-active type transducers, specifically, either piezo-electric or piezo-transducers.
• A golf ball entering the receptacle60 and containing thesensor pad65,66 or67 produces a detectable variance indicating the ball entry event. The variance may be a change in resistance in the case of a piezo-resistive transducer (similar, but not limited to Cooper Instruments LPM 562) or a voltage change in the case of a piezo-electric transducer. As illustrated inFIG. 8, the variance is detected and amplified by an associatedamplifier71. The amplified signal then is input to amicroprocessor72 having an analog to digital signal converting circuit (ADC) and a digital signal encoding circuit connected so as to convert the ADC output representing the sensors signals into a serial digital data stream containing a binary coded word indicating the sensor-ball contact event. Themicroprocessor72 may be the same or similar to themicroprocessor56 of the golf club electronics. A radiofrequency transmitter circuit74 receives the serial digital data from themicroprocessor72 and wirelessly transmit' the information via aninternal antenna76 to the receiver26 (FIG. 1) for subsequent processing by thecomputer28.
• The ball return mechanism68 can be simple as aback plate80 located to be engaged by a golf ball entering thereceptacle22 and supported and biased by a spring or springs82 to eject the ball. Other known ejection devices, similar to those used in pin ball machines and either mechanically or even electrically activated, can be used to improve the effect if desired.
• The receptacle configuration is susceptible to much variation. The receptacle illustrated and described above is well suited to indoor use, on carpet for example. It is clear, however, that an actual cup, installed in an actual green, with real or synthetic grass, can be similarly equipped.
3. Golf Club Motion Sensor Plate
• The golf clubmotion sensor plate80 having atop motion plate82 and abottom motion plate84 is diagrammatically shown inFIGS. 9A-D, wherein thetop motion plate82 contains a plurality of capacitor-forming electrically isolated platelets83 (twelve platelets are illustrated in this exemplary preferred embodiment). They are evenly distributed at or just below the top plate's exteriorupper surface82. Thebottom plate84 has a homogenous electrically conductiveinterior surface85 underlying the platelets83. Each capacitive platelet83 contained in thetop motion plate82 forms a capacitive component when the top and bottom motion plates are vertically closely spaced to form the golf club motion sensor plate. A suitable insulator may be sandwiched between the two plates. The structure is adhesively or otherwise mechanically joined and it may be covered or coated as desired. The result is a golf clubmotion sensor plate80 containing a capacitor matrix (a 3×4 capacitor matrix is illustrated in the preferred embodiment0. The capacitive components83 are connected to form acapacitive network88 as is indicated inFIG. 9E.
• Applying an energizing high frequency alternating electrical signal having a frequency in the range from 100 MHz to 200 MHz from an oscillator87 to the golf club motionplate capacitive network88 produces an electromagnetic field above the surface of each platelet83 of the capacitive components of themotion sensor plate80. Any object, including a golf club, passing near the surface of the energized motion plate will cause a perturbation of the electromagnetic field as illustrated by the samplepossible pathways90 across the plate inFIG. 9C. A network92 of electrical comparator amplifiers (FIG. 9B) is connected to the capacitor network. The comparators of the network92 are connected one to one with the capacitive elements of thecapacitive network88. The comparators of thenetwork88 detect voltage variations occasioned by electromagnetic field disturbance due to a golf cub moving over certain of the capacitive elements of the motion plate. Each different golf club motion over the energized motion plate will produce a uniquely identifiable signal from the comparator amplifier network. There are a variety of known proximity sensors that could be gathered together in an array like that of the platelets83 to serve as the transducer portion of the golf club motion detector.
• The electrical signal from the comparative amplifier network92 is applied to an analog to digital signal converter94 (ADC) and the ADC digitized output signal is converted into a serial digital data stream by amultiplexer96. This data identifies each platelet having had its field disturbed. The serial digital data can be input directly by wire from amultiplexer96 to thecomputer28 located at the site of the golf player and golf clubmotion sensor plate80, or as in the preferred embodiment, illustrated inFIG. 1, the serial data can be transmitted100 and anantenna102, included in the golf club motion electronic transmitter communication circuitry fromFIG. 1.
• Thecomputer28, under the control of the golf system software, will analyze the serial digital club motion signal, recognize from the transmitted signals the platelets83 over which the club head passed and display the golf club swing motion.
4. Wireless Signal Receiver and Computer
• At each player site, a wireless radiofrequency signal receiver26 is connected to thecomputer28 by either the serial (USB) or parallel computer ports, as shown in the functional block diagram,FIG. 10. Thewireless signal receiver26 detects digitally coded radio frequency transmissions from the communication circuit associated with any of asmart golf club20, agolf ball receptacle22, or a golf clubmotion sensing plate24, as shown inFIG. 1. The received transmission are demodulated by the RF receiver circuitry122 (FIG. 10) connected to a microprocessor124, which converts the demodulated data signal to serial binary coded data suitable for communications to acomputer28. Thecomputer28, under the control of the internally installed golf system software program, monitors and directs the flow of communications between remotely located players via the internet and displays the game simulations and performance information. In appropriate installations the wireless electromagnetic signals that communicate with the receiver may be infrared communications.
5. Computer Golfing Software
• At each remote player site, the computer28 (FIG. 1) under the control of the golfing software program (shown in the golfing software system functional block diagram,FIG. 11) monitors and control initialization and the sequential play of the golf game, or alternatively, the individual player practice session. Upon start up by a player at a particular site, the system input parameters are set and the system internet and player port interfaces are initialized130 as indicated by the arrows130aand130b.For internet communications, the serial port listener of thecomputer28 is enabled in the preferred embodiment. A remote player event listener is initialized. It will communicate events from one or more of the smart golf club, the golf ball receptacle and the motion sensor plate. The main operational software (program) thread is run130, and the system awaits data input from the appropriate computer communications ports at132 (port),133 (Remote player Socket Event Listener)
• If the competitive play mode has been selected, the program generates a player participation request and sends134 the request to the GGC game internet server (GGC server)34 (FIG. 1). Upon identification of a player opponent at150 (FIG. 12) by the GGC server, the program initiates the player identification sequence152 and sequential play begins154 (This software sequence and control routine occurs at each remote site where play has been initiated. During thegame play sequences154, the program generates the appropriate animation, display, and audio data and commands136 and138 (FIG. 11), and communicates with the associated display andspeaker devices30 and31 (FIG. 1). Upon the occurrence of a local player event, detected at133, the main operating program at130, displays the event at136, and communicates the event at132 by causing a device transmission at137 to be send at134 via theinternet GGC server135 which displays the event for the opposing player and alerts the opposing player it is his/her turn to play. The local player event may be, but is not limited to the smart golf club impacting a ball, the swing of a club across the sensing plate or the balls entry into the receptacle. The program contains time delay limits for the player action, and delays of play beyond these limits generate play quit and disconnect signals.
• The event at133 also has the effect of indicating at139 that it is no longer the local players turn and enables (as indicated by line139) the serial port listener at132 to detect an event from the remote player, again via the internet.
• If the single player practice mode is selected, the internet communications sequences are disabled, other software sequential operating routines continue as above described and the players golf club stroke, ball-receptacle contact, and/or club swing motion sensor information are communicated only to the computer located at the players site and the performance information analyzed and displayer only at the local players site.
• When a game is won, lose, or terminated, the golf software system generates the appropriate output signals156 (FIG. 12), displays the player performance information, and resets to initial pre-game conditions. If one player opponent quits the game or is “timed out” (due to excessive delay in play) and the remaining player wishes to continue play, the software resumes an internet search for anotheropponent152 and153.
• Using programming as contained in the accompanying microfiche appendix, one skilled in the art can readily accomplish the game programming described. Alternative programming too will be apparent from the foregoing functional description and the illustrations contained in the appended drawings
• While a preferred embodiment has been described, it will be appreciated that many variations and modifications in the system, its operation, and its various components may be made without departure from the spirit and scope of invention as set forth in the appended claims.

Claims (26)

1. A golf club or sports implement motion sensing and direction detection device, comprising:

a plurality of motion sensors uniformity distributed upon or proximate to a device surface area; and

a communications circuit connected with a plurality of sensors to transmit an electromagnetic signal upon one or more of the sensors detecting club motion over the device.

means for acquiring information of a ball-club contact event from a first array of sensors and transmitting these data via a first communications link wirelessly to a receiver for analysis by a first computer;

means for detecting digitally coded wireless transmissions from data derived from data acquired from said first communications link and said first and second contact sensor arrays encompassing a golf ball receptacle, golf club spatial orientation device, or a golf club motion sensing plate, remotely connected to said means for acquiring information of a ball-club contact event from a first array of sensors and transmitting these data via a first communications link wirelessly to a receiver for analysis by a first computer; and

means for a second computer programmed to communicate with one or more said first computers. a third communications link for transmitting data derived from data acquired by said first computers to said second computer. a fourth communications link for transmitting data derived from said data acquired by said second computer to said first computers. wherein said second computer is programmed to cause the transfer of local player events from a remote player site to one or more remote player sites for presentation to said remote players, notify players when it is their respective turn to play, measure player time delays, disconnect remote player sites with excessive time delays, and conduct an internet search for other opponents if the remaining players wish to continue to play. at each remote player site, the computer under the control of the golfing system program, monitors and controls initialization and the sequential play of the golf game, or alternatively, the individual player practice session, electrically connected to said means for detecting digitally coded wireless transmissions from data derived from data acquired from said first communications link and said first and second contact sensor arrays encompassing a golf ball receptacle, golf club spatial orientation device, or a golf club motion sensing plate.

2. The golf club motion sensing and direction detection device ofclaim 1, wherein the plurality of motion detecting sensors comprise a plurality of capacitors connected in a capacitor array and adapted to create electromagnetic fields at an upper surface of the device upon energizing with a high frequency alternating voltage.

3. The golf club motion sensing and direction detection device ofclaim 2, wherein the sensing device is a multilayer plate including at least one continuous conductive layer and a plurality of electrically isolated conductive platelets spaced from and located above at least one continuous conductive layer with a dielectric sandwiched between them to form the motion sensors.

4. The golf club motion sensing and direction detection device of either2 or3, further comprising an array of comparators connected to each one of the sensors.

5. The golf club motion sensing and direction detection device according toclaim 1, wherein the communications circuit includes a wireless electromagnetic signal transmitting circuit.

6. The golf club motion sensing and direction detection device ofclaim 5, wherein the wireless electromagnetic signal transmitting circuit is a radio frequency transmitter.

7. The smart capacitive detective sensor system as recited inclaim 1, further comprising:

a top motion plate, bottom motion plate, homogenous electrically conductive interior surface, capacitive platelet, golf club motion plate capacitive network, capacitive components of the motion sensor plate, network of electrical comparator amplifiers, multiplexer, transmitter, antenna, spatial orientation device golf club motion sensor, for sensing varying characteristics of capacitance representing the velocity, angle, and proximity of a golf club relative to the surface of the device and or spatial orientation devices to detect the rotational orientation, translational path, and directional orientation of said club-head, remotely connected to said wireless signal receiver and computer.

8. The smart capacitive detective sensor system in accordance withclaim 1, wherein said means for detecting digitally coded wireless transmissions from data derived from data acquired from said first communications link and said first and second sensor arrays encompassing a golf club spatial orientation device, or a golf club motion sensing plate comprises a computer, wireless signal receiver, a golf club, golf ball receptacle, golf club motion sensor plate, microprocessor wireless signal receiver and computer.

9. An apparatus comprising: a first electrode; a second electrode located at a distance from the first electrode, the second electrode forming a capacitive element with the first electrode, wherein a gap is present between the first and second electrodes, wherein each of the first electrode and second electrode partially surrounds a member subject to accumulation of frozen material, such that the gap is formed between edges of the first and second electrodes along lateral sides of the member; an electric field sensor having an electrode terminal coupled to the first electrode and providing an electric field output value representative of an amount of frozen material located in the gap between the first and second electrodes; a first insulating layer around the member, between the member and the first electrode and between the member and the second electrode; and a conductive layer around the member, between the member and the first insulator, wherein a shield output of the electric field sensor is coupled to the conductive layer.

10. The apparatus ofclaim 7, further comprising: a coaxial cable, wherein the electrode terminal is coupled to the first electrode via a center conductor of the coaxial cable and wherein a shield output of the electric field sensor is coupled to the conductive layer via an outer shield of the coaxial cable.

11. The apparatus ofclaim 8, wherein the shield output maintains an approximately zero voltage differential between the center conductor and the outer shield.

12. The apparatus ofclaim 7, wherein the second electrode is subject to frost accumulation and the first electrode at least partially surrounds the second electrode.

13. The apparatus ofclaim 7, wherein the member is at least a portion of a cooling element.

14. The apparatus ofclaim 7, further comprising a refrigerator or air conditioner, the refrigerator or air conditioner comprising the first electrode, the second electrode, the electric field sensor, the first insulating layer, and the first conductive layer.

15. The apparatus ofclaim 7, further comprising a transportation device, the transportation device comprising the first electrode, the second electrode, the electric field sensor, the first insulating layer, and the first conductive layer.

16. The apparatus ofclaim 13, wherein the transportation device comprises a window, the window comprising the first and second electrodes.

17. The apparatus ofclaim 14, wherein the first and second electrodes each comprises indium titanium oxide.

18. The apparatus ofclaim 13, wherein the transportation device comprises a wing, the wing comprising the first and second electrodes.

19. An apparatus comprising: a member subject to accumulation of frozen material; a first electrode at least partially surrounding the member; a second electrode at least partially surrounding the member and located at a first distance from the first electrode, the second electrode forming a capacitive element with the first electrode; an electric field sensor having a first electrode terminal coupled to the first electrode and providing an electric field output value representative of an amount of frozen material formed on the member between the first and second electrodes; and a third electrode at least partially surrounding the member and located at a second distance from the first electrode, the first electrode between the second and third electrodes; wherein the electric field sensor comprises a second electrode terminal coupled to the second electrode and a third electrode terminal coupled to the third electrode, and wherein when the first electrode terminal is enabled, the electric field output value is representative of an amount of frozen material formed on the member between the second and third electrodes.

20. The apparatus ofclaim 17, wherein when the first electrode terminal is enabled, the second electrode terminal couples the second electrode to ground and the third electrode terminal couples the third electrode to ground.

21. The apparatus ofclaim 17, further comprising: a first insulating layer at least partially surrounding the first electrode; a first conductive layer at least partially surrounding the first insulating layer, wherein a shield output of the electric field sensor is coupled to the first conductive layer; second insulating layer at least partially surrounding the second electrode; and a second conductive layer at least partially surrounding the second insulating layer, wherein the shield output of the electric field sensor is coupled to the second conductive layer.

22. The apparatus ofclaim 19, wherein the first electrode, first insulating layer, and first conductive layer form concentric rings, and wherein the second electrode, second insulating layer, and second conductive layer form concentric rings.

23. The apparatus ofclaim 17, wherein the member subject to frozen material accumulation comprises a cooling element of a refrigerator or air conditioner.

24. An apparatus comprising: a member subject to accumulation of frozen material; a first electrode at least partially surrounding the member; a second electrode at least partially surrounding the member and located at a first distance from the first electrode, the second electrode forming a capacitive element with the first electrode; an electric field sensor having a first electrode terminal coupled to the first electrode and providing an electric field output value representative of an amount of frozen material formed on the member between the first and second electrodes; a first insulating layer at least partially surrounding the first electrode; a first conductive layer at least partially surrounding the first insulating layer, wherein a shield output of the electric field sensor is coupled to the first conductive layer; a second insulating layer at least partially surrounding the second electrode; and a second conductive layer at least partially surrounding the second insulating layer, wherein the shield output of the electric field sensor is coupled to the second conductive layer; a third insulating layer at least partially surrounding the member, the third insulating layer between the member and the first electrode; a third conductive layer at least partially surrounding the member, the third conductive layer between the member and the third insulating layer, wherein the shield output of the electric field sensor is coupled to the third conductive layer; a fourth insulating layer at least partially surrounding the member, the fourth insulating layer between the member and the third conductive layer; a fifth insulating layer at least partially surrounding the member, the fifth insulating layer between the member and the second electrode; a fourth conductive layer at least partially surrounding the member, the fourth conductive layer between the member and the fifth insulating layer, wherein the shield output of the electric field sensor is coupled to the fourth conductive layer; and a sixth insulating layer at least partially surrounding the member, the sixth insulating layer between the member and the fourth conductive layer.

25. The apparatus ofclaim 22, wherein the first electrode, first insulating layer, and first conductive layer form concentric rings, and wherein the second electrode, second insulating layer, and second conductive layer form concentric rings.

26. The apparatus ofclaim 22, wherein the member subject to frozen material accumulation comprises a cooling element of a refrigerator or air conditioner.

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