WO1990007249A1

WO1990007249A1 - Tongue activated communications controller

Info

Publication number: WO1990007249A1
Application number: PCT/US1989/005573
Authority: WO
Inventors: Daniel Fortune; John E. Ortiz
Original assignee: Zofcom, Inc.
Priority date: 1988-12-16
Filing date: 1989-12-14
Publication date: 1990-06-28
Also published as: CA2005703A1; CA2005703C; AU4806890A

Abstract

A tongue activated communications controller (10) includes an intra-oral transmitter assembly (12) having a keyboard (36) having a plurality of tongue activatable positions (38) for encoding a signal depending on the position activated and a transmitter (98) for transmitting encoded signals. The intra-oral transmitter assembly (12) includes a two sided printed circuit board (20). The first side (22) includes electronics for transmitting signals and the second side (24) includes circuitry for switching from one position to another. The controller (10) further includes a receiver (16) for receiving the encoded signals from the transmitter (98). The receiver (16) sends the signal to a microcomputer (18) for decoding the encoded signals for forming a set of instructions for operating a device from the decoded signal. The microcomputer (18) sends the signals to a device to be operated.

Description

Description TONGUE ACTIVATED COMMUNICATIONS CONTROLLER

Cross-Reference to Other Applications:

This application is related to Mr. Dan Fortune's earlier filed and now abandoned patent application, filed July 18, 1983, seria no. 06/514,973. Technical Field:

This invention relates to the field of communications controllers and more particularly to the field of such controlle which are activated with a user's tongue. Background Art:

A significant portion of persons who do not have the use of their limbs are isolated from daily functioning in society. Some of these persons may have suffered traumatic injuries to their spinal cord, such as during automobile accidents or sport injurie and the like; others may have had diseases of the neuromuscular and central nervous system. In these types of diseases, cognitiv function most often remains intact. It has been found that often these pathologies do not affect the function of the user's tongue The tongue remains accessible as a communications link after all limb control has been lost, even in such progressive neuromuscula diseases, such as multiple sclerosis.

The number of such disabled people is increasing in the general population. Thus, there is an increased need for new devices tha allow the disabled person to work and to have a near-normal lifestyle. With a faster and more aesthetically acceptable communications controller, it is possible for the disabled person to become a productive part of society. There has been a great amount of recent development in this area, particularly in the area of computer controllers for operating mechanical devices.

Current devices exist for hands free computer input. These devices include a mouth stick controller which is a device clenched in the user's teeth and operated by gross head motions to perform various mechanical tasks. This device is utilized primarily by high level quadriplegics and can be wielded with adequate proficiency after some practice. However it requires a high degree of mobility to accomplish specific tasks and is often awkward to use and leads easily to deteriorization of teeth and oral occlusion. Additionally, a mouth stick controller has the limitation that the patient must be in extremely close proximity, in fact a mouth stick controller extends from the mouth to the device being operated.

Voice recognition systems are known. However, further refinement is necessary to produce a reliable method of data communication even for a person having an unimpaired voice. In many cases, quadriplegics have partial paralysis of the diaphragm and larynx. Their speech articulation and volume are severely hampered. Therefore, voice recognition systems, which require good articulation and volume, are not well suited to a broad range of physically impaired persons. Additionally, voice recognition systems present difficulty in environments where multiple users coexist. Other devices proposed to assist the disabled person include many forms of single switch computer control. This type of control is slow to operate and requires many levels of programming. Typically, a single switch actuation device requires an action such as "sip" and "puff" breathing, eyebrow motion, or chin movements to control or to operate a computer, to actuate an environmental control or to achieve personal mobility. Disabled persons with a great degree of mobility and who have a capacity to operate more than one switch desire increased and faster access to a computer. Currently, single switch driven software does not achieve the desired speed that can be obtained by multiple switch inputs.

Another relevant device is an ultra-sonic head controller. This device is limited to the user that is able to produce at least small and precise head movements necessary for keying a computer via ultra-sonic position detectors. The computer recognizes the position of the head and deviations in head positions are interpreted as an analog signal. An example of an ultrasonic device is the Personics View Control System (VCS) , which is currently commercially available. The Personics system includes three ultra sonic transducers housed in a headset to receive a signal transmitted from a control unit. By comparing the signal received at three points on the headset, changes in the angle and rotation of the head are tracked.

Yet another device which is designed for persons of limited mobility is an eye switch apparatus which is an infrared emitter and detector pair mounted on standard eye-glasses. This system operates by emitting small, low power, infrared beams. The reflectivity of the surfaces in front of the emitter can be sensed. For example, when the eyelid opens or closes, an electronics unit activates a relay which serves as a switch. Virtually any body surface can reflect the beam, giving a wide range of threshold levels and possible methods of operation. However, there is a distinct lack of speed in the use of such a device and there is the disadvantage of triggering this type of device unintentionally, such as during normal eye blinking.

The devices currently known are quite limited in the variety of devices they can control. Additionally, presently known devices require physical movements from the disabled user that may not be possible. What is needed is a device which can be used by a large number of persons having limited mobility and which can operate a broad range of devices. The device must not require difficult physical movements for persons suffering from progressive neuromuscular disorders and quadriplegia due to spinal injuries. And, the device should be aesthetically pleasing.

SUMMδRY OF THE INVENTION

It is a general object of this invention to provide a tongue activated communications controller which enables persons of limited mobility to operate various devices.

It is a further object of this invention to provide such a tongue activated communications controller which is well suited for use by persons having quadriplegia due to spinal cord injuries and neuromuscular disorders.

In accordance with the above objects, a tongue activated communications controller in accordance with this invention comprises: an intraoral transmitting assembly including a keyboard having a plurality of tongue activatable positions for encoding a signal depending on the position activated and transmitting means for transmitting the encoded signal; and receiving means for receiving the encoded signals from the transmitting assembly including computing means for decoding the encoded signals and for forming a set of instructions for operating a device from the decoded signals and means for sending the instructions to the device for operation.

In a preferred embodiment, the tongue activated communications controller includes a wire wound around the perimeter of a printed circuit board (hereinafter PC board) to define a high performance inductor embodiment. This enhances the broadcast ability of the controller and allows the user to be farther away from the receiver with acceptable results.

In another preferred embodiment the tongue activated communications controller includes a transmitter for broadcasting encoded signals to the receiver which communicates with a smart box having the computing means. The smart box sends signals to a device to be operated and acts as a controller of that device. Additionally, the preferred embodiment of the smart box includes software for decoding the received signals and for converting the received digital signal into a control signal which could either be an analog signal or a digital signal or even a modified digital signal for operating the desired device.

It is an advantage of the present invention to provide a tongue activated communications controller which is easily used by persons having limited physical mobility.

It is an additional advantage of the present invention to provide such a tongue activated communications controller which can be made to operate a broad range of devices.

It is an additional advantage of this invention to provide such a tongue activated communications controller which can be used by large numbers of persons having quadriplegia due to spinal cord injuries and neuromuscular disorders.

Brief Description of the Drawing:

For a further understanding of the objects and advantages of the present invention, reference should be made to the following detailed description, taken in conjunction with the accompanying drawing, in which like parts are given like reference numerals and wherein:

Fig. 1 is a schematic illustration of the tongue activated communications controller in accordance with this invention illustrating usage with a personal computer, a wheelchair as well as additional applications. Fig. 2 is a partial sectional schematic view of the tongue activated communications controller in accordance with this invention installed in the mouth of the user.

Fig. 3 is a perspective view of the assembled tongue activated communications controller.

Fig. 4 is an exploded perspective view of the tongue activated communications controller of Fig. 3.

Fig. 5 is an enlarged bottom view of the assembled tongue activated communications controller illustrating the electrical circuit of the keypad.

Fig. 6 is an enlarged bottom view of the tongue activated communications controller of Fig. 3.

Fig. 7 is an enlarged cross-sectional view of the keyboard in accordance with this invention.

Fig. 8 is an electrical circuit schematic of the tongue activated communications controller in accordance with this invention.

Fig. 9 is a side perspective view of a second embodiment of the tongue activated communications controller in schematic illustrating a fixed inductor wrapped around the perimeter of a PC board.

Fig. 10 is an electrical circuit schematic of a second embodiment of the transmitter circuit of the tongue activated communications controller in accordance with this invention.

Fig. 11 is a timing diagram illustrating encoded transmission from the tongue activated communications controller in accordance with this invention.

Fig. 12 is a schematic illustration of the encoded signal being received by the tongue activated communications controller in accordance with this invention.

Fig. 13 is a flow chart of the software enclosed in the smart box in accordance with this invention.

Detailed Description of the Invention:

Two embodiments of the tongue activated communications controller will be described below. It will be appreciated that many other embodiments are possible within the spirit and scope of this invention. With particular reference to Fig. 1, there is shown the overall schematic of the tongue activated communications controller, in accordance with this invention, generally designated by the numeral 10. The tongue activated communications controller 10 (hereinafter TACC) is illustrated as interfacing with either a personal computer and/or a wheelchair and/or additional applications. The TACC 10 includes an intra- oral transmitter assembly 12. The intra-oral transmitter assembly 12 fits into the mouth of a user and is held in place therein by press fit. It may also be desirable for the intra-oral transmitter assembly 12 to be held in place in a user's mouth by clasps as illustrated in phantom in Figs. 3 and 4. After installation, the user can transmit encoded signals illustrated by waves 14 to a receiver 16. It is preferable that the transmission be wireless to increase the flexibility of movement of an associated transmitter, however hard-wired embodiments of the TACC are within the scope of this invention. The signals are encoded and are transmitted by the TACC in binary form.

The receiver 16 receives the encoded binary signals and communicates with a smart box 18 which decodes the signals. The smart box 18 comprises a microcomputer; for example, a Z-80 microprocessor or a 4 bit microcontroller would be suitable. The smart box 18 decodes the encoded binary signal and determines which switch on the keyboard has been depressed. The smart box 18 sends a control signal to the desired device for carrying out the appropriate action, such as inputing to a personal computer or directing the motion of a wheelchair. The smart box 18 includes the software for monitoring the received signal and converting it to the appropriate control signal as will be more fully appreciated hereinafter.

With particular reference to Figs. 2-4, there is shown the details of the intra-oral transmitter assembly 12. The intra-oral transmitter assembly 12 includes a PC board 20. The PC board 20 is a two-sided board having a first side 22 with transmitter electronics and a second side 24 with the electrical circuit for the keyboard. Thus, the PC board in accordance with this invention includes both the transmitter electronics and circuitry for switching from one keyboard position to another.

The first side 22 includes an encoder 96, a transmitter 98, a timer 100, an oscillator 102, and a voltage regulator 104. A detailed description of the above elements is set forth below with reference to Fig. 8. The particular electrical devices are preferably low power, high speed semiconductors and are preferably a combination of CMOS integrated circuits and discrete devices. These types of semiconductor devices are preferred because they are compatible with the speed of the 2 MHz crystal oscillator 102.

The intra-oral transmitter assembly further includes an adhesive spacer 26 having a plurality of openings 28 and a keyboard membrane 36 including a plurality of conductive key pad members 38. The keyboard membrane 36 is bonded to the PC board 20 using the adhesive spacer 26. The adhesive spacer 26 is an acrylic adhesive which creates a water tight seal between the keyboard membrane 36 and the PC board 20. The adhesive spacer 26 has channels 27 to permit the movement of air trapped within the channels 27 and the openings 28 as one of the conductive key pad members 38 is depressed by the user's tongue.

The adhesive spacer 26 spaces the membrane 36 away from the second side 24 to prevent short circuiting of the keyboard. Therefore, the adhesive is made from an insulating material, such as an acrylic based adhesive. Additionally, the adhesive spacer 26 acts as a moisture barrier to prevent corrosion and disfunctioning of the electrical circuits. This is especially important since much of the life of the intra-oral transmitter assembly 12 is spent in a moist or wet environment.

In the preferred embodiment, there are three rows of openings 28. The rows have an arc shaped design, designated by the lines having reference numerals 30, 32 and 34 for each of the first, second and third rows, respectively. The arc shaped design accommodates the conductive key pad members 38. The conductive key pad members 38 are similarly divided into three rows 40, 42 and 44, designating the first, second and third rows respectively As will be appreciated from the more detailed explanation found with reference to Figure 6, the conductive key pad members 38 are generally flat and each includes a nipple 92 which protrudes away from the second side of the PC board. Pressure from the tip of a user's tongue deforms the pad members 38 and pushes the conductiv surface of the pad members 38 through the opening 28 of the adhesive spacer 26 and into electrical contact with the second side 24 of the PC board as best shown in Fig. 7.

The intra-oral transmitter assembly 12 is encapsulated by an encapsulant 46 made of methyl methacrylate. As shown more clearl in Figures 2 and 3, the methyl methacrylate encapsulates the PC board 20 the adhesive spacer 26 and the keyboard membrane 36. Th bottom of the operating surface of the keyboard membrane 36 which includes the nipples 92 is exposed for access by the user's tongue and not encapsulated.

The encapsulant 46 has a recess defining a battery compartment 48. Within the compartment 48 are two electrically conductive pads 50 and 52 which are electrically connected to the voltage regulator. A pair of batteries 54 are placed in electrical contact with the pads 50 and 52. In order to protect the user the batteries 54 are sealed in the battery compartment 48 by a gasket 55 and a cover 56. The cover 56 is placed over the batteries 54 for securing the batteries 54 into electrical contact with the pads 50 and 52. The cover 56 includes an electrical contact 57 for bridging the two batteries. The cover 56 is secured to the battery compartment 48 by use of screws 58 and nuts 59 in the battery compartment.

The cover 56 is made from fiberglass and is mounted almost flush with the encapsulant 46. In the preferred embodiment, the encapsulant encapsulates the cover 56. This ensures a comfortable fit of the intra-oral transmitter assembly 12 to the roof of the mouth of the user.

The battery compartment 48 has walls 49 made of A-Butyl Styrene. This provides a double insulation in combination with the encapsulant to limit any passage of fluids or gases between the inside of the battery compartment 48 and the user's mouth.

The encapsulant further has teeth interface members 60 which comprise the shaped outside edges of the encapsulant 46. The edges are shaped in the form of the profile of the inside of the teeth and gums in the mouth of the user. In order to accomplish this, the encapsulant 46 is cast into an impression of the user's mouth, using standard dental techniques. This allows the intra- oral transmitter assembly 12 to be press fit to conform to teeth and gum and the roof of the mouth of the user. Additionally, this procedure ensures that the fit of the intra-oral transmitter assembly 12 will be comfortable and secure within the user's mouth. In some mouths, additional security is desirable. As shown in phantom in Figs. 3 & 4, a clasp 62 can be embedded in the encapsulant 46 and secured to the teeth using standard dental techniques.

With particular reference to Fig. 5, there is shown the second side 24 of the PC board 20 having the electrical circuit for the keyboard. The circuitry is divided into three arc shaped rows 64, 66 and 68. The arc shaped rows 64, 66 and 68 are compatible with the earlier described first, second and third rows, 30, 32 and 34, respectively, of the adhesive spacer 26 and the first, second, and third rows, 30, 32 and 34, respectively, of the keyboard membrane 36. Thus, the conductive key pad members 38 of the keyboard membrane 36 align with the openings 28 of the adhesive spacer 26 which are aligned with the switches 63.

Each switch 63 is approximately 0.175 inch in diameter. The switches 63 are divided into three rows. The first row comprises switches 70, 72 and 74, which are consecutively numbered switches 1, 2 and 3. The second row comprises switches 76, 78 and 80, which are numbered switches 4, 5, and 6. The third row comprises numbered switches 82, 84 and 86 which are switches 7, 8 and 9, respectively.

Each of the switches 63 is generally round in shape. The center-to-center spacing of adjacent switches is approximately equal and is approximately 0.3 inch. This is true except for the center-to-center spacing of switch 2 to switch 4, which is somewhat larger, approximately 0.37 inch. As can be seen from Fig. 5, each of the switches 63 is electrically connected by conductive lines 88 and holes 89 in the PC board 20 to the first side 22 of the PC board 20. Thus, when an electrical connection is made across the switch 63, a signal for that switch is sent to the first side 22 keyboard electronics and transmitted by the intra-oral transmitter assembly 12 to the receiver 16.

With particular reference to Fig. 6, there is shown the bottom side of the keyboard membrane 36. The keyboard membrane 36 is made from mylar and has conductive ink applied to it to create pad members 38. The conductive ink provides a conductive path across one of the switches 63 when one of the corresponding pad members 38 is depressed. The adhesive spacer 26 spaces the keyboard membrane 36 away from the PC board 20 sufficiently (approximately 0.002 inch) so that no electrical contact is made until one of the pad members 38 is depressed. The channels 27 facilitate the depression of the pad members 38 by allowing the displacement of air between the pad members 38 and the PC board 20.

As shown most clearly in Fig. 7, each of the pad members 38 have a nipple 92. The nipple 92 is in the form of a Braille raised dot as to both diameter and shape made with a Braille slate stylus. This provides the user with accurate tactile feedback.

Similar to the switches 63, the pad members 38 are 0.175 inch in diameter. Adjacent pad members 38 are spaced apart 0.3 inch, center-to-center. The distance between the middle pad in the first row 40 and the middle pad in the second row 42, which corresponds to switches 2 and 4 are somewhat larger than the 0.3 inch center to center spacing and match exactly the spacing of switches 2 and 4. The nipples 92 are formed so as to facilitate the detection of one of the pad members 38 with the tongue. Approximately 0.50 ounce of force is required to depress one of the pad members 38 to make electrical contact such that a circuit for switch 63 is completed.

With respect to Fig. 8, there is shown the electrical circuit schematic for the intra-oral transmitter assembly 12. As shown, the assembly 12 includes a keypad 94, an encoder 96, a transmitter 98, a timer 100, an oscillator 102 and a voltage regulator 104. The oscillator 102 preferably oscillates at a fixed frequency of 2MHz.

The keypad 94 comprises the second side 24 switches 1 through 9 as shown in the Fig.8. When one of the switches 63 is closed, an electrical signal is sent to the encoder 96. The signal received is encoded using a decade counter 106; for example, if switch 3, designated by the numeral 74, is closed, an electrical signal is received at Q4 of the decade counter designated by the numeral 108. This is also pin position 10 of the decade counter 106. The signal is encoded and sent to an output of the decade counter designated by Ql and the reference numeral 110. This is also known as pin position 2 of the decade counter.

The encoded output of the decade counter, Q-l, 110, is sent to the first NAND gate 112 of the oscillator 102. The encoded signal sent to the first NAND gate 112 is mixed with a carrier signal created by the oscillator 102.

The oscillator 102 uses a second NAND gate 114, a crystal and appropriate discrete components to generate a 2 MHz carrier signal. The carrier signal is then sent through conductive line 116. The carrier signal is then mixed with the encoded signal at the first NAND gate 112. The output of the mixed signal is sent to the transmitter 98 over conductive line 118.

The transmitter 98 transmits at 2 MHz frequency using the carrier signal created by the oscillator 102. In the embodiment of the transmitter 98 shown in Fig. 8, the transmitter 98 has a variable inductance and can be adjusted to tune the resonant frequency of the transmitter 98 to the carrier signal of 2 MHz

The receiver 16 detects, the encoded signal from the intra-oral transmitter assembly 12 and filters out the carrier signal. The encoded modulated signal, which remains, is passed to the smart box 18, and decoded to determine which switch on the keyboard has been depressed. The smart box 18 translates the encoded modulated signal into a control signal for controlling and operating various devices, as shown in Fig. 1. The control signal may be analog or digital in nature. The operation of the receiver 16 and smart box 18 will be more fully appreciated with ref rence to Figs. 11 - 13.

The frequencies of the various modulating signals transmitted by the intra-oral transmitter assembly 12 are determined by the timer 100. The voltage regulator 104 reduces the battery voltage potential of nominally 6V to a potential of 3.3V. This provides the power to the semiconductor devices, the decade counter 106 and NAND gates 111. The 3.3V potential also represents the binary high for the digital logic. The 3.3V potential is sent over conductive line 120 to the decade counter enable 122 of the decade counter 106. This is also known as pin position 14 of the decade counter 106.

Thus, when the voltage regulator 104 provides the 3.3V signal, the decade counter 106 is enabled and the clock input 124 is tied to the timer 100. As can be seen, the clock input 124 is tied to the output of the timer 100 by conductive line 126 and the voltage regulator output is tied to the decade counter enable 122 by conductive line 120. Thus, when the clock is enabled, an encoding signal corresponding to one of the switches 63, namely the switch depressed, is sent from the decade counter 106 to the oscillator 102 and then transmitted.

With particular reference to Fig. 9, there is shown a second embodiment of the intra-oral transmitter assembly generally denoted by the numeral 130. In the second embodiment, there is a groove 132 of about .25 inch in depth around the perimeter of the PC board 20. The wire is wound around the PC board replacing the variable inductance surface mounted component of the earlier described embodiment. Magnet wire 133 of 39 gage is tightly wound around groove 132 and is held in place thereby. Wrapping the magnet wire 133 creates an inductor having a fixed value, in the preferred embodiment, the value ranges between 2.8 μH and 10 μH. Unlike the first embodiment the inductance can not be varied after assembly. However, the inductance can be measured on a case by case basis. The magnet wire 133 is connected to the first side 22 of the PC board in the same location where the variable inductor was found in the first embodiment 12.

As can be appreciated, a new transmitter circuit, generally designated by the numeral 135, is necessary to accommodate the second embodiment of the intra-oral transmitter assembly 130. The corresponding circuit diagram is shown in detail in Fig. 10. The transmitter assembly 130 includes a fixed inductor 134 which comprises the magnetic wire 133 wound around the PC board groove 132, as described earlier. The inductor 134 is a fixed value that ranges between 2.8 μH and 10 μH. The transmitter assembly 130 further includes a pair of 1000 pF capacitors and a tuning capacitor 136. The tuning capacitor 136 is inserted into the circuit to assure that the tuned resonant frequency of the transmitter matches the 2 MHz carrier. The value of the tuning capacitor 136 is selected accordingly. This ensures the signal is accurately received by the receiver 16.

When the signal is transmitted, it is done so by a wireless transmission. If it was desirable for there to be a hard wire between the intra-oral transmission assembly 12 and the smart box 18, the signal would be tapped directly from the output of the decade counter 106. In this embodiment no transmitter or oscillator would be necessary.

Fig. 11 illustrates the encoding of the signal transmitted by either of the intra-oral transmitter assemblies 12 or 130. The timer sends out a clock signal represented by pulse line 140. When none of the switches 63 has been activated, no signal is sent out from the decade counter 106. This is schematically represented by a straight pulse line 142. When one of the switches 63 is depressed a unique pulse line is generated. For example, when switch 1 has been depressed, a pulse line 144 is created. Pulse line 144 is a square wave line having a period of

2 T, where T is one timer period. This form of modulation is called pulse coded modulation.

Coded pulse line 144 is then combined with the 2 MHz carrier and forms pulse line 145. Pulse line 145 is then transmitted to the receiver 16 where the carrier is filtered out and the signal decoded.

When switch 2 is depressed, a pulse line 146 having a period of

3 T (1 T high and 2T low) is created. Pulse line 146 is combined with the 2 MHz carrier to form pulse line 147 and is then transmitted to receiver 16. Similarly, when switch 3 is depressed a 4 T (I T high and 3 T low) pulse line 148 is created. Again, it is combined with the carrier and transmitted. The remaining switches 63 follow the same pattern.

Fig. 12 illustrates receipt of the wireless transmission of the signal from either of intra-oral transmitter assemblies 12 or 130. As described above, the receiver filters out the carrier portion of the signal. The receiver 16 is a modified AM receiver which has been tuned to the carrier frequency of 2 MHz. This is done by adjusting the core and changing the capacitors to stabilize the reception by minimizing drift. The receiver 16 uses an amplitude modulation detection scheme to recover the encoded signal.

The receiver 16 sends the demodulated , encoded signal to a comparator 150 which converts the wave form into binary format. The comparator 150 sends the signal to a digital filter 152 which converts the encoded signal into a square wave. The digital filter 152 sends the resulting, filtered signal to the smart box 18.

The smart box 18 comprises a standard microcomputer architecture. The preferred embodiment of the smart box includes a single board computer which has a plurality of input and output ports, e.g. Prolog, STD-7000 System 7806 Z-80A Multifunction CPU card 7904 TTL Decoded 1/0 Utility Card. The smart box 18, using the software described in detail below, generates a control signal for controlling and operating various devices. The control signal may be digital or analog or a modified digital signal. The control signal may be altered as needed using the smart box and the system software.

In order to generate the correct signal, the smart box 18 uses the system software to determine which switch has been depressed and activates its own corresponding switch to direct the desired device to perform the desired function.

The system software referenced above will now be described with reference to Fig. 13. At the top level of the software, there are two software loops operating at all times. The main routine is called TOP, generally designated by the numeral 154. TOP performs initial and preparatory routines and then enters into a repeating loop. Within this repeating loop the computer executes the MAP- SWITCH 158 subroutine which selects the mapping of the switch position identification for different keyboard layouts. Upon completion of MAP-SWITCH 158, TOP 154 enters another subroutine called RUN-MODES 160. After executing RUN-MODES 160, the software checks for keyboard inputs in another subroutine called 7TERMINAL 162. If a key is activated on a programmer's computer, the Main Event loop within TOP 154 ends. This programmer's computer is connected to the smart box 18 only during programming and testing. Otherwise, the Main Event loop repeats, continuing with the MAP- SWITCH subroutine. The Main Event loop is comprised of MAP-SWITCH 158, RUN-MODES 160 and ?TERMINAL 162. The TOP 154 routine remains within the RUN MODES 160 as long as one of the pad members 38 is depressed to cause activation of one of the switches 63.

At regular .512 msec intervals, the computer halts whatever it is doing in the TOP routine and executes another routine called TICKER, generally designated by the numeral 164. TICKER 164 is the interrupt service routine which reads the binary signal from the receiver 16 and updates the clock variables to reflect the time between each low to high transition edge of the pulse, line as described with reference to Fig. 11. The TICKER 164 routine prepares data to be sent out to those devices which require repeating outputs, for example, a Macintosh computer mouse port. In other cases, routines within RUN-MODES 160 send out control information directly without using TICKER 164, for example wheelchair controllers. The TICKER 164 routine calculates the length of time between successive low to high transition edges and stores information in the software variables NEW-CLOCK and OLD- CLOCK. These variables are read into RUN-MODES 160 to determine which of the switches 63 has been closed.

There are several software subroutines within the smart box 18. As shown in Fig. 13 there is an initialization subroutine called INITS, designated by the reference numeral 156, which performs the functions of initializing variables, and configuring the timers in the smart box 18 necessary for the interrupt service routine. INITS 156 also performs a one time initialization of variables handled regularly within the interrupt service routine, TICKER 164, and establishes the location of TICKER 164 in memory. The TICKER 164 routine runs whenever its interrupt is encountered and handles all timing calculations.

Additionally, INITS 156 performs the functions of preparing the variables used in identifying each switch 63, configuring the va^'riables that control the acceleration behavior of a device such as a computer mouse and configuring the motorized wheelchair controller so that the wheelchair is stationary upon initial operation.

The MAP-SWITCH 158 contains a simple one to one table which changes the logical identity associated with each switch so that the switches 1 through 9 can be mapped anywhere on the keypad.

The RUN-MODES 160 selects one of the available operation modes which the smart box 18 operates. For example, the modes in the smart box 18 are ?TEST, MOUSE or CHAIR. ?TEST configures the operation of the intra-oral transmitter assembly 12 into a test mode; MOUSE converts operation of the intra-oral keypad into a Macintosh mouse emulation; and CHAIR converts the operation of the intra-oral keypad into the directional control of a powered wheelchair. Other additional operational modes can be added as required and then the smart box will behave in one of these modes as desired.

In the CHAIR mode, the user depresses one of the conductive key pad members 38 to control a motorized wheelchair. In a preferred embodiment a DUFCO controller is used and the CHAIR subroutine produces the output necessary to operate such a controller. The user can move one of 8 directions; forward, forward right, right, ...or send a stop signal.

The CHAIR mode includes a lower level subroutine entitled, TACC- KEY? which examines the switch closure data from either one of the transmitter assemblies 12 or 130 to determine which switch if any, has been closed. There are several error suppression algorithms within the TACC-KEY? subroutine to minimize the effect of key bounce and transmission signal degradation.

The CHAIR mode includes another lower level subroutine entitled, RUN-CHAIR, which reads which switch the user has closed and performs a table look-up to determine which bits (binary values) to set high or low in the output signal. This output signal is composed of a four bit word: a forward bit, a reverse bit, a left bit and finally a right bit. These bits determine the direction that the wheelchair moves. All acceleration and velocity ramping is handled by the DUFCO wheelchair controller hardware. These bits form a command instruction for the wheelchair controller and when outputted, the wheelchair controller responds with movement.

An additional low level CHAIR subroutine is entitled, STOP-CHAIR which sets the four bit signal sent to the DUFCO wheelchair controller to zero. This instructs the wheelchair to stop.

The mouse mode includes low level routines which translate switch closure into Macintosh mouse emulation. The algorithm for performing this emulation is set forth in Appendix A, which represents the source code for the above software, is attached hereto and made part hereof.

While the foregoing detailed description has described several embodiments of the tongue activated communications controller in accordance with this invention, it is to be understood that the above description is illustrative only and not limiting of the disclosed invention. Particularly, any number of devices, including environmental controls, computers, telephone, musicals instruments and other devices could be operated by the tongue activated communications controller in accordance with this invention. It will be appreciated that all such embodiments are within the scope and spirit of this invention. Thus, the invention is to be limited only by the claims as set forth below.

Claims

What is claimed is:

1. A tongue activated communications controller, comprising: an intra-oral transmitting assembly including a keyboard having a plurality of tongue activatable positions for encoding a signal depending on the position activated and transmitting means for transmitting the encoded signal; and receiving means for receiving the encoded signals from the transmitting assembly including computing means for decoding the encoded signals and for forming a set of instructions for operating a device from the decoded signals and means for sending the instructions to the device for operation.

2. A controller as set forth in Claim 1, wherein the intra- oral transmitting assembly includes a two sided printed circuit board, having a first side for the electronics for transmitting an electrical signal and a second side having the circuitry for switching depending on the position activated.

3. A controller as set forth in Claim 2, wherein the intra- oral transmitting assembly transmits using a wireless transmitter having an inductor.

4. A controller as set forth in Claim 3, wherein the printed circuit board has a perimeter, and wherein an inductor is wound around the perimeter for enhanced transmission.

5. A controller as set forth in Claim 4, wherein the perimeter of the printed circuit board has a .25 inch recess.

6. A controller as set forth in Claim 1, wherein the intra- oral transmitter assembly includes a two sided printed circuit board having a first side including electronics for transmission, the electronics comprising low power, high speed semiconductor devices.

7. A controller as set forth in Claim 6, wherein the first side of the printed circuit board includes an encoder, voltage regulator, timer, oscillator and transmitter.

8. A controller as set forth in Claim 1, wherein the keypad has nine discrete positions.

9. A controller as set forth in Claim 8, wherein the keypad has three arc-shaped rows, and each row having three key positions.

10. A controller as set forth in Claim 1, wherein the intra- oral transmitter assembly includes a two sided printed circuit board having a first side with transmission electronics and a second side with circuitry for switching positions, a keyboard membrane having an operational surface with a plurality of key positions and an adhesive spacer between the printed circuit board and the keyboard membrane, and wherein the printed circuit board, adhesive spacer and keyboard membrane are encapsulated by an encapsulant suitable for use in a human mouth with the operational surface of the keyboard membrane exposed.

11. A controller as set forth in Claim 10, wherein the printed circuit board is bonded to the keyboard membrane by the adhesive spacer for creating a moisture resistant barrier.

12. A controller as set forth in Claim 10, wherein the adhesive spacer spaces the keyboard membrane away from printed circuit board approximately 0.002 inch.

13. A controller as set forth in Claim 10, wherein the operational surface for the keyboard membrane includes a plurality of spaced apart, separate conductive pads for making electrical contact with the printed circuit board.

14. A controller as set forth in Claim 12, wherein each pad has a nipple which can be depressed by a human tongue.

15. A controller as set forth in Claim 13, wherein each of the nipples is a Braille nipple and provides tactile feedback for a human tongue.

16. A controller as set forth in Claim 10, wherein the encapsulant having an outer edge which define means for interfacing with the teeth and forming a press-fit connection therewith.

17. A controller as set forth in Claim 15, wherein a clasp is embedded into the encapsulant for securing the intra-oral transmitter assembly in the mouth of a user.

18. A controller as set forth in Claim 10, wherein the encapsulant is made from methyl methacrylate.

19. A controller as set forth in Claim 10, wherein the encapsulant has a top surface defining a recess for a battery compartment.

20. A controller as set forth in Claim 15, wherein the intra- oral transmitter assembly includes two lithium coin sized batteries which fit inside the battery compartment.

21. A controller as set forth in Claim 16, wherein the battery compartment includes a cover.