Patent Publication Number: US-11650102-B2

Title: Adjustable dwell time for motion detector based on activity

Description:
BACKGROUND 
     I. Field of the Invention 
     The present invention relates to home security and, more particularly, to a system, method and apparatus to extend battery life for motion detectors. 
     II. Description of Related Art 
     Home security systems are very popular in the United States and abroad. Such home security systems typically comprise a security panel and a number of sensors distributed around the home to detect unauthorized entry and/or movement inside the home. For example, a home may have all of its doors and windows monitored by installing a wireless door/window sensor onto each door and window of the home to detect unauthorized entry, and one or more motion sensors installed at one or more points inside the home for detecting unauthorized movement within the home. Each of the sensors may transmit a wireless signal to the security panel, where the security panel may take further action once a signal has been received from one of the sensors, such as to sound a siren inside the home or contact a remote monitoring facility. 
     In addition to the popularity of home security systems, home monitoring and control systems are now becoming widespread. Such systems allow users to monitor their home security systems, turn lights on and off remotely, lock and unlock doors remotely, as well as to better control home heating and air conditioning systems. In the latter category, battery-powered, home occupancy sensors are being used to automatically control operation of heating and air conditioning systems when the sensors detect the presence of an occupant or not. 
     Motion sensors utilize a “dwell time”, or delay time, that prevents transmissions once movement is detected. Without this, as a person, for example, moves across a room, a motion sensor might continuously transmit a “motion detected” signal, needlessly draining its battery well before an expected battery life. 
     If the dwell time is set too long, for example 3 minutes or longer, a motion sensor may not capture all motion events. For example, an authorized person may move through a room, causing the motion sensor to transmit a motion detected signal. However, if a burglar enters the room within the dwell time, the motion sensor will not transmit another motion detected signal. 
     If the dwell time is set too short, a motion sensor will transmit more often when continuous motion is detected. For example, if the dwell time is set to 15 seconds, a motion detector would transmit a motion detected signal every 15 seconds while motion is present. This needlessly drains the battery. 
     It would be desirable to overcome the limitations of a fixed dwell time in security motion detectors in order to maximize battery life. 
     SUMMARY 
     A system, method and apparatus for automatically adjusting a dwell time of a motion detector based on detected activity in an area monitored by the motion detector. In one embodiment, a motion detector is described, comprising a detector for detecting a presence of a person in an area, a memory for storing processor-executable instructions and a dwell time, the dwell time comprising a minimum time period in which to transmit successive motion detection signals, a transmitter for transmitting the motion detection signals, and a processer coupled to the detector, the memory and the transmitter, for executing the processor-executable instructions that causes the motion detector to determine, by the processor, a level of activity in the area, based on the level of activity, adjust, by the processor, the dwell time to a new dwell time, and store, by the processor, the new dwell time in the memory. 
     In another embodiment, a method is described for automatically adjusting a dwell time of a motion detector based on detected activity in an area monitored by the motion detector, comprising determining, by a processor of the motion detector, a level of activity in the area, based on the level of activity, adjusting, by the processor, the dwell time to a new dwell time, and storing, by the processor, the new dwell time in the memory. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments and certain modifications thereof when taken together with the accompanying drawings in which: 
         FIG.  1    is a top, plan view of a home or business monitored by a security system comprising a motion detector  102  configured to automatically adjust a dwell time of the motion detector based on detected activity in an area monitored by the motion detector; 
         FIG.  2    is a functional block diagram of the motion detector as shown in  FIG.  1   ; 
         FIG.  3    is a functional block diagram of a personal communication device used to monitor and/or configure the motion detector as shown in  FIG.  1   ; and 
         FIGS.  4 A,  4 B and  4 C  represent a flow diagram illustrating one embodiment of a method for automatically adjusting a dwell time of a motion detector based on detected activity in an area monitored by the motion detector. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure describes a motion detector that automatically adjusts its “dwell time” based on activity levels detected in an area monitored by the motion detector. A “dwell time”, as described herein, comprises a time period during which the motion detector does not transmit a “motion detection” signal after detecting motion. It should be understood that throughout this disclosure, the terms “level”, “rate” and “frequency” may be used interchangeably. 
       FIG.  1    illustrates a top, plan view of a home or business monitored by a security system comprising a motion detector  102  used to monitor an area  100  in the home or business and central controller  104 . In this example, the security system comprises only motion detector  102  and central controller  104 . However, security systems typically comprise additional components, such as one or more door/window sensors, garage tilt sensors, glass break sensors, sirens, etc. These components have been omitted in order to focus on motion detector  102 . 
     Area  100  generally comprises a room, hallway, entryway, or some other portion of a residence or business. Motion detector  102  comprises a sensor/transmitter combination for determining the presence of one or more persons in area  100 , and for transmitting “motion detected” signals wirelessly to central controller  104  when motion is detected. Motion detector  102  may comprise a battery-powered motion sensor using passive infra-red (PIR) detection techniques, as known in the art, to detect infra-red heat as a person moves across area  100 . Motion detector  102  may, alternatively or in combination, comprise an occupancy sensor, used to determine the presence of one or more persons in area  100  using techniques such as ultrasonic, infra-red, thermal, or other well-known techniques to determine if a person is occupying area  100 . Unlike traditional motion (PIR) sensors, occupancy sensors generally do not require movement of a person in order to detect their presence. 
     Motion detected signals are transmitted to central controller  104 , upon detection of a person in area  100 , in accordance with a dwell time stored within motion detector  102 , as will be explained in greater detail later herein. In one embodiment, the dwell time is a static time period following a detection of motion. In another embodiment, the dwell time is a “sliding” time period, i.e., a fixed time period that is reset each time that motion is detected. For example, if the dwell time is 1 minute, and motion is detected, a software timer is started that determines if no further movement occurs during the dwell time. If no movement is detected during the dwell time, motion detector  102  will transmit a “motion detected” signal the next time it detects motion. On the other hand, during the dwell time, if further movement is detected, motion detector  102  will refrain from transmitting a “motion detected” signal and reset the software timer to the dwell time, where motion detector  102  will not transmit a “motion detected” signal from the time the that the further movement is detected until the end of the dwell time, assuming no additional movement is detected during this time period. 
     Central controller  104  comprises a home security panel, gateway, hub or some other device that monitors motion detector  102 , as well as other sensors and/or home monitoring and control devices, installed within area  100  or other areas of a home or business. Examples of central controller  104  include a GC3 Security &amp; Control panel sold by Nortek Security and Control, Inc., a base station sold as part of an alarm security kit by Ring, Inc., a Pulse® interactive touch screen panel sold by ADT, Inc. In other embodiments, controller  104  may not be used. In these embodiments, motion detector  102  is monitored by a remote server  110  in communication with motion detector  102  via a wide-area network  108 , such as the Internet, and a local-area network (LAN)  106 . In the remaining disclosure, any reference to central controller  104  may include reference to remote server  110 . In some embodiments, central controller  104  comprises both security and home monitoring and control functionality. Finally, central controller  104  may communicate with remote server  110  via local-area network  106  and wide-area network  108  where central controller  104  lacks independent means to send alerts or other information externally to area  100 . 
     When central controller  104  receives a signal from motion detector  102  when the security system is in an armed mode of operation, or some other security or home monitoring sensor, central controller  104  may perform one or more actions, such as to contact a remote, security monitoring facility (not shown) via wide-area network  108 , or by some other means, such as via cellular communication technology. Alternatively, or in addition, central controller  104  may cause a siren (not shown) inside of area  100 , or elsewhere in another location inside a home or business, to sound, and/or a strobe light (not shown) to flash. 
     The dwell time and/or a rate of change of the dwell time may be programmed remotely using a personal communication device  112 . Personal communication device  112  may comprise a fixed or mobile computing device, such as a laptop or desktop computer, or it may comprise a mobile phone, tablet computer, wearable device, or some other device capable of wireless communications with motion detector  102 , either directly or indirectly via local-area network  106  and/or wide-area network  108  (when personal communication device  112  is located outside of area  100  and out of range of local-area network  106 ) and also offering a user interface for monitoring and/or programming the dwell time and/or rate of change. Personal communication device  112  is configured to run an executable software program, or “app”, that allows a user to perform these actions. In one embodiment, personal communication device  112  communicates with remote server  110 , which stores account information for thousands, or millions, or users, each who have one or more motion detectors in their respective homes or businesses. In this embodiment, a user account may store a current dwell time of motion detector  102  or a dwell time rate of change metric, which indicates how quickly the dwell time will change, based on an activity level in area  100 , as will be explained later herein. The dwell time and/or rate of change may then be provided to motion detector  102 , where it is stored in memory. 
       FIG.  2    is a functional block diagram of one embodiment of motion detector  102 . In this embodiment, motion detector  102  comprises a processor  200 , a memory  202 , a sensor  204 , and a transmitter  206 . It should be understood that the functional blocks may be connected to one another in a variety of ways, that additional function blocks may be used (for example, amplification or filtering), and that not all functional blocks necessary for operation of motion detector  102  are shown for purposes of clarity, such as a power supply. 
     Processor  200  is configured to provide general operation of motion detector  102  by executing processor-executable instructions stored in memory  202 , for example, executable code. Processor  200  typically comprises a general purpose processor, such as an ADuC7024 analog microcontroller manufactured by Analog Devices, Inc. of Norwood Mass., although any one of a variety of microprocessors, microcomputers, microcontrollers, and/or custom ASICs selected based on size, cost, power consumption, computing power, and/or other factors. 
     Memory  202  is coupled to processor  200  and comprises one or more non-transitory, information storage devices, such as RAM, ROM, flash memory, or virtually any other type of electronic, optical, or mechanical information storage device. Memory  202  is used to store the processor-executable instructions for operation of motion detector  102  as well as any information used by processor  200 , such as a dwell time that defines how often motion detector  102  may transmit when a person is detected and/or a dwell time rate of change, which defines how quickly the dwell time will change based on the level of activity in area  100 . Memory device  202  could, alternatively or in addition, be part of processor  200 , as in the case of a microcontroller comprising on-board memory. 
     Sensor  204  is coupled to processor  200  and comprises a sensor and related circuitry and, in some embodiments, firmware, to detect the presence or absence of one or more persons in area  100 . Sensor  204  may comprise one or more passive infra-red (PIR) detectors (for detecting motion of an infra-red emitting body), ultrasonic detectors (for detecting a doppler shift from a reflected body), heat or thermal detectors (for determining a temperature change), carbon dioxide sensors (for detecting the presence of carbon dioxide), microwave sensors (for detecting a doppler shift from a reflected body), a keycard detector (for determining when a hotel guest has inserted a hotel key card), and/or a camera (using firmware to detect a shape in the form of a person). 
     Transmitter  206  is coupled to processor  200  and comprises circuitry necessary to transmit wireless signals from central controller  104 , local-area network  106  and/or personal communication device  112 . Such circuitry is well known in the art and may comprise BlueTooth, Wi-Fi, Z-wave, Zigbee, X-10, RF, optical, or ultrasonic circuitry, among others. In some embodiments, transmitter  206  additionally comprises a wireless receiver for receiving signals from central controller  104 , local-area network  106  and/or personal communication device  112 , such as programming commands to modify the dwell time rate of change. 
       FIG.  3    is a functional block diagram of one embodiment of personal communication device  112 , showing processor  300 , memory  302 , user interface  304 , and one or more transmitters  306 . It should be understood that the functional blocks shown in  FIG.  3    may be connected to one another in a variety of ways, and that not all functional blocks necessary for operation of personal communication device  112  are shown (such as a power supply), for purposes of clarity. 
     Processor  300  is configured to provide general operation of personal communication device  112  by executing processor-executable instructions stored in memory  200 , for example, executable code. Processor  300  typically comprises one or more microprocessors, microcontrollers, or custom ASICs that provide communications functionality to personal communication device  112  as well as to execute instructions that provide an ability for personal communication device  112  to monitor and configure motion detector  102  to change the dwell time and/or change the dwell time rate of change. 
     Memory  302  is coupled to processor  300  and comprises one or more non-transient information storage devices, otherwise referred to as one or more processor-readable mediums, such as RAM, flash memory, or virtually any other type of electronic, optical, or mechanical information storage device. Memory  302  is used to store the processor-executable instructions for general operation of personal communication device  112  (for example, communication functionality), one or more dwell times, and in some embodiment, a dwell time rate of change. 
     User interface  304  is coupled to processor  300  and allows a user to monitor and configure motion detector  102 . User interface  304  may comprise one or more pushbuttons, touchscreen devices, electronic display devices, lights, LEDs, LCDs, biometric readers, switches, sensors, keypads, microphones, speakers, and/or other human interface devices that present indications to a user or generate electronic signals for use by processor  300  upon initiation by a user. A very popular user interface today is a touchscreen device. 
     Transceiver  206  comprises circuitry necessary to wirelessly transmit and receive information to/from personal communication device  112 , such as one or more of a cellular transmitter, a Wi-fi transmitter, a Bluetooth transmitter, a cellular data transmitter, an Ethernet adapter, and/or some other type of wireless means for communications. In some embodiments, more than one transmitter is present, for example, a cellular transmitter and a Wi-Fi transmitter. Such circuitry is generally well known in the art. 
       FIG.  4    is a flow diagram illustrating one embodiment of method, or algorithm, performed by motion detector  102  and personal communication device  112 , for automatically changing the dwell time of motion detector  102  based on activity levels occurring in area  100 . It should be understood that in some embodiments, not all of the steps shown in  FIG.  4    are performed and that the order in which the steps are carried out may be different in other embodiments. It should be further understood that some minor method steps have been omitted for purposes of clarity. 
     The process begins at block  400 , where motion detector  102  is programmed with a default dwell time and, in one embodiment, a default dwell time rate of change. This typically occurs during the manufacturing process. A typical default dwell time is one minute. 
     At block  402 , motion detector  102  monitors area  100  for movement of a person by processor  200  evaluating signals from sensor  204 . Sensor  204  typically generates a signal when motion is detected and provides it to processor  200 . Processor  200  evaluates the signal to determine whether movement is present in area  100  using techniques well-known in the art. 
     At block  404 , if movement is detected, processor  200  causes transmitter  206  to transmit a “movement detected” signal. 
     At block  406 , processor  200  determines an activity level, frequency or rate, associated with area  100 . An “activity level” comprises an indication of activity in area  100 , expressed either at a level, rate or frequency. For example, if a single person enters area  100 , sensor  204  will generate a signal and provide it to processor  200 . Processor  200 , in turn, processes the signal and determines that movement has been detected in area  100 . The person who entered area  100  may continue to move around in area  100  over time. As a result, sensor  204  continues to generate signals in response to sensing this additional movement and provides those signals to processor  200  for processing. Processor  200  may make multiple determinations during this time period, based on the signals, that additional movement is occurring in area  100 , i.e., determine an activity level based on the frequency of motion determinations made by processor  200 . 
     In another example, multiple people may enter and occupy area  100 . Motion may be sensed by motion detector  102  as explained above after a first person enters area  100 . As additional people enter area  100 , and as these people move around area  100 , sensor  204  may generate numerous signals over time as movement of each person is detected. As such, processor  200  will receive and process these signals, determining that movement is occurring frequently in area  100 , such as determining that movement has been detected every second for a predetermined number of seconds, such as 10 seconds, or determining that movement has occurred a number of times that exceeds a predetermined threshold, such as, such as 3 movement detections over a 20 second time period. In these embodiments, processor  200  determines an activity level based on the frequency of motion determinations made by processor  200 . In another embodiment, processor  200  determines an activity level by periodically checking sensor  204  to see if sensor  204  has determined any movement in area  100  since the last time processor  200  checked sensor  204 . For example, processor  200  may evaluate sensor  204  every 2 minutes, and determine an activity level of “1” when activity is detected that meets or exceeds a predetermined consecutive number of times, such as three consecutive times, or a predetermined number of times within a predetermined time period, such as 2 times every 3 minutes. 
     At block  408 , in some embodiments, processor  200  assigns a value to the activity level. For example, a “1” can be assigned when the activity level exceeds a first level, and a “0” can be assigned when little or no activity is sensed. In another embodiment, processor  200  may assign a value between 1 and 10, or 1 in 5, etc., to indicate the activity level. In this embodiment, memory  202  may store a number of activity levels based on the frequency of motion detections. For example, the numerical value assigned by processor  200  when no movement is detected over a predetermined time period may be the lowest value, i.e., “1” in the two examples provided above, the numerical value increasing as the frequency of movement is detected. The numerical value may be stored in memory  202  representing the current activity level. 
     At block  410 , after detecting a second instance of activity when additional movement is detected, as described above, processor  200  determines whether to cause transmitter  206  to transmit a “movement detected” signal by evaluating the current dwell time. In this example, the dwell time is stored in memory  202  as 1 minute. Therefore, if the second instance of additional movement is detected within a 1 minute period, processor  200  does not cause transmitter  200  to transmit a “movement detected” signal. 
     At block  412 , in response to determining the increased activity level or rate in area  100 , processor  200  may automatically increase the default dwell time by a predetermine time when the activity level (i.e., frequency of detected movement) exceeds a predetermined threshold. For example, if the frequency of detected movement exceeds one per 30 second time period, processor  200  may increase the default dwell time to 2 minutes. If additional movement is detected within another predetermined time period, such as in the following 2 minutes, processor  200  may again increase the dwell time, for example to 3 minutes. Note that the amount of dwell time increase is not limited to linear values. For example, upon detecting additional movement in the following 2 minute time period, processor  200  may increase the dwell time to 5 minutes. As the dwell time increases, motion detector  102  transmits fewer “motion detected” signals, thereby increasing battery life. 
     In another embodiment, processor  200  may increase the dwell time continuously at a dwell time rate of change stored in memory  202 , i.e., change the dwell time a predetermined time while the activity level exceeds a predetermined threshold. For example, the dwell time rate of change may be stored in memory  202  is 1 minute of dwell time change every two minutes that the activity level exceeds 2 determinations per minute, processor  200  will increase the dwell time by 1 minute every minute, typically until the dwell time reaches a maximum value, such as 30 minutes. 
     At block  414 , in an example where multiple people are in area  100 , most or all but one of the people may leave area  100 . 
     At block  416 , as a result of most or all but one person leaving the area, processor  200  detects a decrease in the activity level in area  100 . For example, after the people have left area  100 , processor may only detect instances of movement sporadically, for example once every two minutes, or 3 times over a 5 minute time period. 
     At block  418 , in response to determining a decreased activity level or rate in area  100 , processor  200  decreases the dwell time. For example, if the number of motion detections per time decreases below a predetermined threshold, such as one detection every two minutes, processor  200  may decrease the dwell time by a fixed amount, such as from 10 minutes to 2 minutes, or to a fixed value, such as 3 minutes. Multiple predetermined thresholds may be stored in memory  202 , each indicating a particular activity level or frequency, each predetermined threshold associated with a particular dwell time value. For example, for an activity level of 10 detections every minute, the associated dwell time could be 8 minutes, and for an activity level of 1 detection every two minutes, the associated dwell time could be 5 minutes. 
     In another embodiment, processor  200  could reduce the dwell time based on the rate of change of the activity level. For example, when the activity level drops 10%, processor  200  may decrease the dwell time by 10% or by some other figure not associated with the percentage drop in detections. Additionally, the decrease may not be linear. For example, if the activity level drops by 10%, processor  200  may decrease the dwell time by 20%, and if the activity drops another 10%, processor  200  may decrease the dwell time by 30%. 
     In yet another embodiment, processor  200  may decrease the dwell time continuously at a dwell time rate of change stored in memory  202 , i.e., change the dwell time a predetermined time while the activity level remains below a predetermined threshold. This dwell rate may be the same or different than the dwell rate of change as described above. Processor may continue continuously changing the dwell time until it reaches 0 or some other relatively small time period, such as 15 seconds. 
     At block  420 , when processor  200  determines movement as a result of evaluating signals from sensor  204 , processor  200  checks memory  202  to determine a current value of the dwell time, as it may have changed since the last time processor  200  caused transmitter  206  to transmit a “motion detected” signal. Processor  200  refrains from causing transmitter  206  to transmit a “motion detected” signal when an elapsed time from a previous transmission does not exceed the current dwell time. 
     At block  422 , a user may launch an application on personal communication device  112  to monitor and/or configure motion detector  102 . The application may initiate a session with remote server  110  to access an account where information pertaining to motion detector  102 , and associated information such as an owner&#39;s name, address, phone number, account number, email address, etc., may be stored. In other embodiments, personal communication device  112  communicates with motion detector  102  either directly (i.e., using Bluetooth or BLE), or indirectly (i.e., via local-area network  106 ). 
     At block  424 , processor  300  of personal communication device  112  may present an electronic user interface for monitoring and/or configuring motion detector  102  to the user via user interface  304 . The electronic user interface is typically a graphical user interface, allowing the user to determine a status of motion detector  102  (such as whether motion detector  102  is connected to central controller  104 , an operating mode of motion detector (i.e., “walk test”, normal), a current setting for the dwell time, a current setting for the dwell time rate of change, an estimated battery life of motion detector  102 , etc.) and also to allow the user to make certain modifications to motion detector  102  (i.e., to change the dwell time and/or to change the dwell time rate of change, in embodiments where processor  200  changes the dwell time based on the dwell time rate of change). The electronic user interface may comprise one or more drop-down menus, slider bars, entry boxes, etc. to allow the user to change the dwell time and/or dwell time rate of change. 
     At block  426 , the user may modify the dwell time rate of change, or any of the thresholds that help determine various activity levels, using the user interface displayed on user interface  304 . The user may wish to decrease the dwell time rate of change, for example, if motion detector  102  is transmitting too frequently, or to increase the dwell time rate of change when motion detector  102  is failing to transmit “motion detected” signals as quickly as desired by the user. For example, if a current dwell time rate of change is 1 minute of change every 2 minutes that an activity level exceeds a predetermined threshold, the user may desire that the dwell rate of change be set to 1 minute of change every minute that the activity level exceeds the predetermined threshold, or to 20 seconds of dwell time change for every two minutes that the activity level exceeds the predetermined level. 
     At block  428 , an indication of the new dwell time rate of change, and/or change in threshold level(s), of is provided from user interface  304  to processor  300 . 
     At block  430 , processor  300 , in turn, generates a command to change the dwell time rate of change, or threshold level(s), and causes the command to be transmitted to remote server  110  and/or motion detector  102 , via transmitter  306 , which may include an identification of a particular motion detector  102  to be modified. The command may include the new dwell time rate of change, or the new dwell time rate of change may be transmitted in a separate message or command, or the, new threshold level(s). In another embodiment, the changes are not provided to remote server  110  and/or motion detector  102  until the user is satisfied that the new dwell time rate of change, or changes to the threshold value(s) will not have undesired battery life implications, as described below. 
     At block  432 , remote server  110  may receive the command/new dwell time rate of change, and/or change in threshold level(s), from personal communication device  112  and store the new dwell time rate of change, and/or change in threshold level(s), in an associated database in accordance with the particular motion detector  102  identified by personal communication device  112 . Remote server  110  may then forward the new dwell time rate of change, and/or change in threshold level(s), to motion detector  102 . 
     At block  434 , processor  200  receives the command/new dwell time rate of change, and/or change in threshold level(s), via transmitter  206  (in this case, again, transmitter  206  additionally comprises a receiver). Processor  200  may determine that the command comprises an instruction to change a current dwell time rate of change, and/or change in threshold level(s), stored in memory  202  with the new dwell time rate of change by comparing the command to a plurality of commands, such as a command to change the dwell time rate of change, and/or change in threshold level(s), a command to reset motion detector  102 , a command to provide the status of motion detector  102 , a command to enter into a walk test mode of operation from a normal mode of operation, or other commands. When processor  200  determines that the command is a command to change the dwell time rate of change, and/or change in threshold level(s), processor  200  stores the new dwell time rate of change, and/or change in threshold level(s), in memory  202  in place of the previous dwell time rate of change, and/or change in threshold level(s). Thereafter, processor  200  may use the new dwell time rate of change to change, and/or change in threshold level(s), the dwell time, as explained above. 
     At block  436 , processor  200 , or the app running on personal communication device  112 , may determine a remaining or expected battery life for the battery(ies) that power motion detector  102  in response to changing the dwell time rate of change or change in threshold level(s) In one embodiment, processor  200  measures a voltage of the battery(ies) as motion detector  200  transmits a signal, as current is drawn from the battery(ies) during transmission. The voltage level may be compared to an expected battery voltage when the battery(ies) are new, and the deviation from the expected battery voltage indicates a remaining battery life. 
     In another embodiment, memory  202  may receive a standard battery life of motion detector  102  via remote server  110  at some point during a setup process, identifying an expected battery life for a particular make and/or model of motion detector  102  at a default dwell time, and a default dwell time rate of change. As the dwell time rate of change is increased from the default dwell time rate of change, processor  200  may estimate the remaining or expected battery life, based on the default battery life and the new dwell time rate of change. For example, if the expected battery life of motion detector  102  is 36 months using a dwell time rate of change of 1 minute of dwell time change each time the activity level exceeds 1 detection every two minutes, processor  200  may determine an estimated or expected battery life of 48 months, depending on factors such as the amount of power consumed by motion detector  102  during transmission “movement detected” signals and the number of expected transmissions given that an increase of the dwell time rate of change will typically result in fewer transmissions, resulting in an increase to battery life, as opposed to a greater number of “movement detected” signals when the dwell time rate of change is decreased. 
     At block  438 , processor  200  may transmit the remaining or expected battery life to remote server  110  and/or personal communication device  112  via transmitter  206 . 
     At block  440 , processor  300  in personal communication device receives the remaining battery life and may store the remaining battery life in memory  302 . 
     At block  442 , processor  300  may display the remaining battery life to the user via user interface  304 . 
     At block  444 , the user may choose to again modify the dwell time rate of change, or change in threshold level(s), if the user determines that the expected or remaining battery life is unacceptable to the user, based on the change previously submitted. In one embodiment, when the user enters a desired, new dwell time rate of change, the desired, new dwell time may not be implemented by motion detector  102  until the app running on personal communication device  112 , or motion detector  102 , calculates the expected or remaining battery and displays it to the user for approval. Upon approval from the user, the desired, new dwell time rate of change, and/or change in threshold level(s), is implemented by motion detector  102   
     Therefore, having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth in the appended claims.