Abstract:
An apparatus and method for behavior monitoring and training for an animal, comprising a remote unit with a microprocessor, accelerometers, stimulators, and batteries. The remote unit microprocessor receives monitoring and training instructions from a host unit and signals from the accelerometers. The remote unit, when placed on an animal, produces training stimuli, including sound and/or electric shock, in response to digging and jumping. When a microphone and receiver are also employed in the remote unit, the remote unit can also produce training stimuli in response to barking and leaving a confined area.

Description:
This application claims the benefit of an earlier filed copending provisional patent application titled “MCU/Sensor Based, Canine Aversion Therapy, Behavior Modification Device,” application No. 60/110,071, filed Nov. 27, 1998, the disclosure of which is hereby incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of electronic animal training devices, and more particularly, to an electronic device that automatically and independently trains an animal not to vocalize, not to dig, and not to jump on people, and to remain within a designated area. 
     BACKGROUND OF THE INVENTION 
     Electronic dog training collars that provide warning sounds, followed by some form of punishment for the purpose of training dogs not to engage in nuisance barking are well known. This type system is activated when a dog&#39;s barking sound is picked up from the dog&#39;s throat area by a sound-sensing device located on a dog collar. This type device does not allow a user selectable time delay before corrective action, currently thought to be desirable. This type device also does not allow a user a selectable option to apply correction only at night when barking is most objectionable. 
     Electronic dog training collars that provide warning sounds, followed by some form of punishment for the purpose of training dogs to stay within an established area are also well known. This type system is activated when a collar based radio receiver picks up a signal transmitted through a buried wire antenna. This type device does not provide a method for allowing the dog to return to within the established area in the event he escapes, without receiving correction. 
     A third type of electronic dog training collar provides warning sounds, then some form of punishment only when perceived behavioral problems are visually detected by the dog owner who activates a radio transmitter contained within a hand held radio transmitter enclosure. This signal, in turn, is received by a dog collar based radio receiver and the correction sequence is initiated. Some training collars of this type have a tilt switch which senses whether a dog is moving or standing still (pointing). This training method may allow dog owner frustration to enter into the training process which can result in over correction, causing additional behavioral problems. 
     In all of the above-described systems, warning sounds are provided by a buzzer or loud speaker. Punishment stimuli include electronic stimulation, loud and/or high-pitched sounds, chemical sprays, and flashing lights. 
     The inventor of the present invention discovered through intensive field work with dogs, that with the use of accelerometers, an associated microprocessor containing unique software algorithms, and supporting circuitry, the detection of heretofore undetectable and undesirable behaviors such as digging and jumping up on people and/or objects is practical. After detection the microprocessor directs the system to provide owner prerecorded voice warning, and if selected, an optional electronics based stimulus. 
     Acceleration-sensitive motion analyzers use acceleration sensors that are attached to an object under study which can continuously monitor the motion of the object. Accelerometers are used in such diverse areas as industrial, medical, railway, automotive and aerospace engineering. The accelerometers used in these devices may detect either or both, dynamic and static acceleration, and are capable of providing electrical output signals to a microprocessor and/or a data recorder. 
     SUMMARY OF THE INVENTION 
     The present invention provides an apparatus and method for monitoring and training a canine, and has potential uses in the monitoring and training of any quadrupedal animal. In a preferred embodiment all hardware and software associated with the training functions are located within a remote electronics enclosure which is attached to a dog harness at the shoulder blade area. The electronics and software located within this electronics enclosure are capable of monitoring, based on owner selected preferences, one or more of the following behaviors: digging behavior, jumping up behavior, nuisance barking behavior, and movement relative to a buried wire antenna enclosure or running away behavior. An accelerometer system located in the center of the electronics enclosure is used in detecting the digging and jumping up behavior, a microphone located in the bottom of the electronics enclosure and just above the dog&#39;s chest area is used in detecting barking vibrations through the chest cavity, and a receiver located within the electronics enclosure is used in picking up signals from the buried wire antenna if and when the dog comes within the transmission range of the buried wire antenna Processing of motion data, sound data, and buried wire antenna proximity data is accomplished by a microprocessor and its associated unique software algorithms contained within the electronics enclosure. The functions of the hardware and software contained within the remote electronics enclosure are selected by the user, and the batteries are recharged, while the remote electronics enclosure is connected to a host unit using a custom designed, magnetic latching connector. The user is allowed the option of inputting his or her own voice commands, selecting one or more of the four (4) possible system functions described above, as well as selecting various options within each function, for example an option is available to correct for nuisance barking only at night. The selections of these options is accomplished using a four keypad, a LCD and its associated messages, and prerecorded voice assistance messages. All options are available to the user by selecting the ‘yes’ or the ‘no’ key and stepping through the host program decision tree. All user interface functions of the host unit are controlled by the microprocessor contained within the host unit. All training instruction options and user recorded voice commands are passed to the microprocessor and voice data storage chip located within the remote electronics enclosure. The remote electronics enclosure unit is completely independent from any user input once the unit is removed from the host unit and placed in the dog harness and into use. This independence insures that the device is incapable of producing overcorrection and associated unsafe situations for the dog. 
     It is an object of the present invention to provide an electronic device for an animal that monitors behavior, including vocalization, digging, jumping, and approaching a containment wire. 
     Another object of the present invention is to monitor digging and jumping in an animal using an accelerometer. 
     Another object of the present invention is to use an accelerometer, microphone, and a receiver simultaneously to monitor behavior in an animal. 
     Another object of the present invention is to train an animal by monitoring behavior such as vocalization, digging, jumping, and approaching a containment wire and by using stimulators such as voice commands, electric shocks, or a combination thereof. 
     Another object of the present invention is to provide a remote unit contained in a harness attached to an animal to monitor and modify behavior independently. 
     Another object of the present invention is to provide a remote unit contained in a harness attached to an animal to receive transmissions from a containment wire defining a containment area, warn or punish when the containment wire is approached or traversed, and allow reentry into the containment area without punishment. 
     Another object of the present invention is to provide a host unit with a microprocessor allowing inputting monitoring and training instructions into a remote unit having a microprocessor, adjusting operating parameters in the remote unit microprocessor, and navigating through a decision process to select active functions, voice messages, sound levels, electric stimulation voltage level, and electric stimulation duration. 
     Another object of the present invention is to provide a host unit having a transmitter for an integrated boundary wired containment system and a battery charging system to charge batteries in a remote unit. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects, and advantages will become more fully apparent from the following description, appended claims, and accompanying drawings in which: 
     FIG. 1 illustrates the remote unit docked in the host unit. 
     FIG. 2 illustrates the placement of a remote unit on a dog. 
     FIG. 3 is a block diagram of a preferred embodiment of the host unit of the present invention. 
     FIG. 4 is a block diagram of a preferred embodiment of the remote unit of the present invention. 
     FIG. 5 is a flow diagram of the functions of the host unit. 
     FIG. 6 is a flow diagram of the functions of the remote unit. 
     FIG. 7 shows a preferred embodiment of a navigation sequence for programming the remote unit with the host unit. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows a preferred embodiment of the present invention comprising a remote unit  10  and a host unit  17 , with remote unit  10  “docked” in host unit  17 . The remote unit has a microphone  14  on the underside, and a loudspeaker  16 . Host unit  17  has a keypad  18 , with a display unit  34 , for providing input necessary for adjusting operating parameters of remote unit  10 . 
     FIG. 2 shows a remote unit  10  inserted into a harness  11  in place on a dog  12 . Detail A shows the positioning of the various devices used by remote unit  10 . Stimulation electrodes  13  provide electrical paths to dog&#39;s  12  skin. The microphone  14  picks up noise from dog&#39;s  12  chest cavity and is used to sense vocalization, such as, for example, barking. Remote unit  10  has a light emission display (LED)  15  which is an ultra-bright device capable of being seen through a wide field (130°) of vision. A loudspeaker  16  provides audible user voice commands to dog  12 . 
     FIG. 3 illustrates the components of host unit  17 . Power supply  30  supplies low voltage DC power to host unit  17 . Charger circuit  31  is controlled from processor  32  and monitors a battery  59  (see FIG. 4) in remote unit  10  via an in-circuit serial programmable (ISP) port  33  and supplies an appropriate charge when remote unit  10  is docked in host unit  17 . A user interface function is provided by keypad  18  and a display unit  34 , preferably a two-line liquid crystal display (LCD) character display. Keypad  18  and display unit  34  are controlled by processor  32 . Processor  32  generates a continuous pseudo random phase encoded sinusoidal low frequency ac signal, for a wired containment system, which is amplified and filtered by amplifier  35  to transmit to and drive an external containment fence antenna  36  surrounding a containment area in which an animal is to be confined. This wired containment system is a subsystem of the host unit  17  and provides a corresponding electromagnetic field throughout the length of the buried wire antenna  36 . Amplifier  35  ensures that a constant signal current is supplied to external antenna  36 , independent of the length of antenna  36 , up to the operating limits of host unit  17 . 
     Host unit  17  with a remote unit  10  in the docked position, provides for monitoring and charging remote unit batteries  59  (FIG.  4 ), setting and monitoring all control options, recording and playing back user voice messages and playing back preinstalled programming guidance messages. With remote unit  10  removed from the host unit  17 , host unit  17  can, if selected as a user option, provide the transmitter for an integrated dog boundary wired containment system. Host unit  17  can serve as the host for an unlimited number of remote units  10 . 
     Microprocessor  32  provides for programming and central control of all host activities including necessary control, monitoring, programming, and serial communication with the remote unit microprocessor  51  (see FIG.  4 ), while docked, and for signal processing and display functions. Display  34  provides the user, while remote unit  10  is in the docked position, a means to visually display current operating parameters of remote unit  10 , and as a visual interface to be used in conjunction with the keypad  18  in viewing and altering operating parameters of remote unit  10 . 
     Loud speaker  16  provides the user, while a remote unit  10  is in the docked position, audible prerecorded programming guidance messages indicating current system operating system parameters etc., and providing an audio interface to be used in conjunction with the keypad  18  to alter operating parameters of a remote unit  10 . Loud speaker  16  is connected to and controlled by host unit  17  using a serial bidirectional serial connector  33  when a remote unit  10  is docked to the host unit  17 . 
     Microphone  14  (see FIG. 4) provides the user, while a remote unit  10  is in the docked position, a means for recording voice input for dog behavior correction and reward command messages into the remote unit voice processing circuit. This microphone  14  is located on remote unit  10  but serially connected to and controlled by the host unit when the remote unit is docked to the host unit  10 . 
     Keypad  18  provides, while remote unit  10  is in the docked position, input necessary for adjusting operating parameters of the remote unit  10 . A PIN number (security number) can be required and entered before changing function options. A user can navigate through a decision process in selecting active functions, voice messages, sound levels, stimulation circuit voltage levels, stimulation duration, correction delays, etc. In a preferred embodiment navigation is accomplished by selecting either ‘yes’ or ‘no’ keys on keypad  18 . Two other keys allow the user to navigate back to the last screen display or navigate forward to the next screen display. A battery charger  31  provides the means to safely charge, monitor, and maintain a good charge condition for a NiMH battery contained within the remote unit, via a serial connector. 
     In an alternative embodiment, host unit  17  also has a standard serial port for connection to a personal computer to allow for remote firmware upgrades for the microprocessor operating systems of both host unit  17  and remote unit  10  via the Internet or a disk, with supplied communication software, such as in PC or MAC format, for example. This embodiment also provides for reviewing, and setting of all functions, levels, durations and user messages within a PC or MAC environment. 
     FIG. 4 shows the components of remote unit  10 . The dual axes accelerometer  50  provides digital signals to microprocessor  51  proportional to vertical and horizontal orientation, and dynamic movement. Processor  51  checks these signals and decides if they justify a stimulus, by checking against the user defined parameters for that function. Only if a stimulus is required will the selected stimulus be delivered, at the level set, for the duration set. The accelerometer  50  is used to determine two functions, digging and jumping up. 
     The microphone  14  is used to detect vocalizations, preferably from the chest cavity of the animal, which are amplified by the audio amplifier  52  before being fed into microprocessor  51  for analysis. It is also used to allow user recorded messages to be input, and saved in voice circuit  53  when remote unit  10  is docked with host unit  17 . If the vocalization is of sufficient magnitude and duration, as set by the user, the selected stimulus will be delivered at the level set and for the duration set. This stimulation may be adapted after a user selects a time delay and may be applied, if selected, only at night. 
     An internal antenna  54  picks up containment signals when the animal moves within range of the containment wire. These signals are amplified by the receiver/amplifier  55  and fed into microprocessor  51  for analysis and decoding. Detection is triggered at two levels, for a warning stimulus, as the animal nears the inner confinement region of the containment wire, and another stimulus as the animal crosses the containment wire to the outer containment region. The stimulus provided, levels, and duration are all selected and set by the user within predefined limits. The phase of the signal is analyzed by microprocessor  51 , which decodes the signal by regenerating pseudo random information in the same fashion as the transmitter and is used to determine which side of the containment wire fence the animal is on, by comparing the decoded phase with that received. If the phase is opposite to that expected, microprocessor  51  decides that the animal has escaped outside the containment area, and disables any stimulus. This allows the animal to return. 
     The stimulus selected can be one of two types, voice messages/sounds replayed from voice circuit  53  via audio amplifier  60  into loudspeaker  16  or a short pulsed electric shock, delivered via two metal collar studs, generated by shock circuit  57 . The levels of each of these and the duration are independently selectable by the user. Voice circuit  53  is also used by host unit  17 , when remote unit  10  is docked, to provide prerecorded user messages during programming/charging. Shock circuit  57  is a separate module within the unit and may be omitted if not required by the user. 
     Microprocessor  51  saves power by shutting down the system into a sleep mode, and only waking to process signals at intervals. It does this by controlling the power management circuit  58 . During the short wake mode, microprocessor  51  also drives a high intensity LED  15  to provide indication of system function. Low battery is indicated by the lack of pulsing LED. This also provides a useful beacon function during low light conditions. Power management circuit  58  also saves power, in the wake mode, by only selecting one sensing circuit at a time in succession. The system also shuts down anytime the animal is not moving, for example, when the animal is asleep, which may be as much as 60% of each day. The result is very low power consumption, enabling long periods of use between battery charges. 
     Battery  59  is a NiMH type providing high energy density in a small size, and having no memory effect. This provides at least 1000 charge/discharge cycles before replacement is necessary. 
     The ISP port  33  connects with the host unit  17  when docked and provides two-way digital serial communication between the two units. The same port also automatically connects battery  59  for charging and analysis. 
     A light dependent resistor (LDR)  61  allows remote unit  10  options to be day or night selective. This light sensor  61  is employed to allow barking to go uncontrolled during daylight hours, and stimulus only applied at night, when most nuisance barking occurs. 
     Remote unit  10 , when in use as an intelligent remote device, is attached to but removable from a supplied animal harness with pouch. It is programmable by host unit  17 . It is an intelligent unit, which includes an audio system for recording (when attached to the host unit  17 ) and playing back remotely (when used on an animal), user voice correction and reward messages. Accelerometer  50  provides detection of static and dynamic acceleration. Stimulation circuitry module  57  provides physical behavioral correction. Internal antenna  54  and receiver/amplifier  55  provide for reception of the containment subsystem signals, which are decoded by microprocessor  51 . A high intensity LED  15  acts as battery monitor and night location beacon. 
     Microprocessor  51  provides central control, monitoring and signal processing functions for all remote unit activities. In this capacity, the microprocessor initiates, via loud speaker  16  and/or stimulation circuitry  57 , audible and/or electrical stimulus to the animal, when selected animal behavior criteria fall outside predefined limits. 
     Accelerometer  50  provides monitoring of animal body movement and provides input to microprocessor  51 . Many kinds of motion sensors may be suitable for this purpose. A preferred embodiment is accelerometer  50 , known in the art. It is a complete 2-axis accelerometer with a 2 g measurement range. It can measure both dynamic acceleration as well as static acceleration forces, including acceleration due to gravity, so the sensor can be used to measure X and Y tilt where it is placed. When the accelerometer is oriented so both the X and Y axes are parallel to the earth&#39;s surface it can be used as a two axis tilt sensor with a roll and pitch axis. Ninety degrees of roll would indicate that the dog is laying on its side. In addition, when the accelerometer indicates no movement at all, regardless of the orientation of the dog, the dog is asleep or inactive and the system is powered down, as described above. Thus, the accelerometer can readily detect when the dog is not standing. The accelerometer is placed directly above, the shoulder blades and is contained within remote unit  10  and associated dog harness  11  as described in FIG.  2 . 
     With regard to digging movements of the dog, the accelerometer can detect forward motion (dynamic motion) or lack of forward motion of the dog, in addition to X and Y tilt. If the accelerometer detects that the dog&#39;s forward motion has stopped and a motion perpendicular to the main axis of the dog continues, the dog is digging. If this criteria is used in conjunction with accelerometer recognition of a downward tilt toward the front of the dog&#39;s body, the digging motion is firmly established. The accelerometer can easily detect when the dog is not standing and the dog can only dig when standing. Thus, the digging detection can be disabled automatically when the dog is laying down, rolling over, etc. With regard to jumping, when the accelerometer detects a movement essentially straight up, or up and slightly rearward, the dog is jumping up. Based on these criteria, standard software programming can be used to detect and report digging or jumping. 
     Voice generating circuit  53  and power amplifier  60  are under control of microprocessor  51  providing user correction and reward audio data to loud speaker  16 . Microphone  14  provides monitoring of vocalization through the body cavity and provides audio signal input to amplifier  52  and microprocessor  51  while remote unit  10  is on the dog. Loud speaker  16  provides audible animal correction and reward commands while the remote unit  10  is on the dog. 
     Stimulation circuitry module  57  provides a series of voltages form 500 volts to 4500 volts, if/as selected by the user when remote unit  10  is docked to host unit  17 . This voltage correction provides a maximum current of 200 micro-amps for less than 25 milliseconds in a burst. Duration is from one to a maximum often seconds, as selected by the user when remote unit  10  is docked to host unit  17 . A user can select a delay time period of from one minute to ten minutes of continuous barking, before applying voice and/or correction stimulation, due to the fact that a dog barks as naturally as human beings talk. This is consistent with the LDR feature  61  which allows remote unit  10  to be day or night selective. To attempt to eliminate all barking is thought to be cruel and counterproductive. 
     Dog containment is within an area enclosed by a boundary wire antenna. The encoded pseudo-random electromagnetic signal generation and processing used in this system ensures that the voice and/or correction stimulus is used only for containment, and operates only as the dog moves near to and through the containment wire antenna to the ‘outside’ area. The correction capability is then disabled by microprocessor  51  to allow the dog reentry into the containment area, without receiving correction. The correction capability is then restored by microprocessor  51  to address the next move near to or through the containment wire antenna to the ‘outside’ area. 
     When the dog enters the electromagnetic field radiating from external antenna  36  transmitted from host unit  17  which is generating pseudo-random encoded signals, internal antenna  54  and receiver/amplifier  55  located within remote unit  10  pick up the signal and send it to microprocessor  51  for decoding. Microprocessor  51  determines the strength of the containment signal to find out how close the animal is to the containment fence. If it falls within the warning region, the selected training stimulus is provided to deter further movement in that direction. Should this fail and the containment signal grows stronger, signaling a move closer towards the fence, the main stimulus is provided. If the dog chooses to ignore this or moves at great speed to rush the fence, thereby rendering any system ineffective, the dog passes over the containment fence toward the outside of the containment area. The signal is still being received by remote unit  10 . Microprocessor  51  now determines from the change in phase of the containment signal, that the dog is outside the containment area and cancels any stimulus so that the dog may return to the containment area. 
     If the dog moves outside the range of the containment signal and outside the containment area, microprocessor  51  determines this and provides a voice message (for example, “GO HOME!) from loudspeaker  16 . If the dog moves back towards the containment fence to return within the containment region and the containment signal is received by the remote unit, microprocessor  51  determines from the phase of the containment signal, that the dog is outside the containment area and moving in, and thus cancels the audible beep (or voice message) and suppresses any stimulus to allow the dog to return. When the dog returns within the containment fence and within the allowed region, microprocessor  51  now determines, from the loss of containment signal and the previous condition, that the dog has returned and resumes normal operation. 
     FIG. 5 is a flow diagram of the functions of the host unit. When power is first applied to host unit  69  the microprocessor performs a standard initialization procedure  70  and standard function checks  71  and displays a welcome  72 . If no remote unit is detected by the host unit and the wire fence is enabled, then the pseudo-random signals are transmitted to the antenna until a remote unit is docked  73 . The remote unit is then checked for correct function and the battery condition assessed  74 . The functions selected in the remote unit are read into the host unit  75  and then displayed on the display  76  of the host unit. The battery charger is then started  77 . If editing of the functions is required, this is done  78  and the new functions are transmitted to the remote unit  79 . The battery charge continues until the battery is fully charged and then the battery charger switches into a low current maintenance charge  80  until the remote unit is removed  81 . The system then resets  82  and starts again  69 . 
     FIG. 6 is a flow diagram of the functions of the remote unit. The remote unit will start  90  when power from the battery is available and the unit is turned on. The remote unit maintains a low level of initialization  91  by following a continuous cycle  112  enabling each part of the circuit in turn in order to reduce power consumption. If the remote unit is docked with the host unit, the host unit will interrogate the remote unit  92  and the remote unit will respond to the host unit  93  so that functions can be downloaded from the host unit to the remote unit. 
     When the remote unit is attached to the animal, the beacon LED  94  and LDR  113  are on when the unit is “awake” and monitoring and training. If the fence function is enabled  95  it is checked for containment. If the animal approaches the fence a fence warning signal is created  96  and a warning stimulus is provided to the animal  97 . If the animal is close to the fence  98  a deterrent stimulus is provided to prevent escape  99 . If the bark function is enabled  100  and barking is detected  101 , the appropriate stimulus is provided to prevent barking  102 . If the dig function is enabled  103  and digging is detected  104 , the appropriate stimulus is provided to prevent digging  105 . If the jump function is enabled  106  and jumping is detected  107 , the appropriate stimulus is provided to prevent jumping  108 . The beacon is turned off  109  and the unit is sent to sleep for a short period of time  110 . The unit then resets  111  and the cycle is repeated continuously  112 , independently of a user, as long as the battery supplies power. In this regard, the monitoring and training of the animal is “turned over” to the remote unit and the presence of a user is not required. 
     FIG. 7 shows a preferred embodiment of a navigation sequence for programming the remote unit with the host unit. The user visual interface can be a 2×16 character Liquid Crystal Display providing a display for 32 alpha numeric characters. The ‘User Interface’ subsystem ‘starts up’ when the remote unit is placed in the host unit  120 . A system test is performed on the host and the remote microprocessor to test for functionality  121 . A sound system test is performed to test for a comfortable user volume for the prerecorded messages played throughout the programming process  122 . The user can at this point adjust the volume of these messages  123 . This volume has no effect on the ‘user voice correction’ messages played while the remote unit is on the dog. The user is allowed to select a ‘voice only’ or ‘electronic stimulation only’ form of correction or may select a ‘voice and electronic stimulation’ form of correction  124 . The volume is then set for the voice correction to be used while the remote unit is on the dog  125 . If the user has selected voice and electronic stimulation correction, the user then selects a duration (time) for the stimulation to occur. A period of from one (1) second to a maximum of ten (10) seconds may be selected. A voltage to be applied, of from 500 volts to 4500 volts is then selected  126 . The user then views the currently selected working functions; jumping up, fence, barking, and digging  127 . The current working functions may be from none (0) to four (4). The user may then set new working functions and sub functions  128 . The user may add to an existing function or may eliminate a function and make a new function operative. The containment system or ‘fence’ has two user selectable options. The proximity or nearness to the fence before a warning is given may be selected  129 . The proximity or nearness to the fence before a correction is given may be elected  130 . The barking system has two user selectable options. The system may be set to function only at night when most nuisance barking occurs  131 . The system may be set to function only after a user selectable delay of from one minute to ten minutes  132 . 
     Although this aspect of the invention has been described with respect to the embodiment illustrated in FIGS. 1-7, various alternatives may be used without departing from the scope of the invention. For example, stimulators delivering stimuli other than sound or electric shock may be used. A host unit and a remote unit may be contained in a single unit. A non remote unit using a tether may be used. A PC may serve as a host unit for providing instructions to the remote unit. The remote unit may be modified so that it can be controlled remotely by a user to train the animal directly. The remote unit may be constructed or used to train only a single behavior. The present invention may also be used to monitor and train other behaviors such as running, sleeping, rolling on the ground, eating, and the like. Various types of power supplies and batteries may be used, and different transmission signals may be used. The invention may be applied to many other kinds of animals in addition to dogs. Many other types of motion sensors may be applied to detect various movements. 
     It will be understood that various changes in the details, materials, and arrangements of the parts which have been described and illustrated above in order to explain the nature of this invention may be made by those skilled in the art without departing from the principle and scope of the invention as recited in the following claims: