Sensor fusion door status detection

A method of monitoring a door of an elevator car within an elevator system including: detecting a first plurality of accelerations along an X-axis of the elevator system during a first time period; detecting a second plurality of accelerations along a Y-axis of the elevator system during the first time period; determining an absolute value of the first plurality of accelerations; determining an absolute value of the second plurality of accelerations; determining a first summation of the absolute value of the first plurality of accelerations and the absolute value of the second plurality of accelerations; and determining whether the door of the elevator car is in motion during the first time period by determining whether a maximum value of the first summation is greater than a threshold value.

BACKGROUND

The embodiments herein relate to the field of conveyance systems, and specifically to a method and apparatus for monitoring a position of a conveyance apparatus of a conveyance system.

A precise position or status of a conveyance apparatus within a conveyance systems, such as, for example, elevator systems, escalator systems, and moving walkways may be difficult and/or costly to determine.

BRIEF SUMMARY

According to an embodiment, a method of monitoring a door of an elevator car within an elevator system is provided. The method including: detecting a first plurality of accelerations along an X-axis of the elevator system during a first time period; detecting a second plurality of accelerations along a Y-axis of the elevator system during the first time period; determining an absolute value of the first plurality of accelerations; determining an absolute value of the second plurality of accelerations; determining a first summation of the absolute value of the first plurality of accelerations and the absolute value of the second plurality of accelerations; and determining whether the door of the elevator car is in motion during the first time period by determining whether a maximum value of the first summation is greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: adjusting the threshold value if the maximum value of the first summation is less than a selected value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: detecting a third plurality of accelerations along an X-axis of the elevator system during a second time period; detecting a fourth plurality of accelerations along a Y-axis of the elevator system during the second time period; determining an absolute value of the third plurality of accelerations; determining an absolute value of the fourth plurality of accelerations; determining a second summation of the absolute value of the third plurality of accelerations and the absolute value of the fourth plurality of accelerations; and determining whether the door of the elevator car is in motion during the second time period by determining whether a maximum value of the second summation is greater than the threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: determining that the door of the elevator car is in motion during the first time period and the second time period; determining that the second time period occurs at greater than threshold time period after the first time period; and determining that the door was in a reversal motion during the first time period.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: determining that the door of the elevator car is in motion during the first time period and the second time period; determining that the second time period occurs at less than threshold time period after the first time period; determining that the door was in an opening motion during the first time period; and determining that the door was in a closing motion during the first time period.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: determining that the maximum value of the first summation is greater than a threshold value; and determining that a door of the elevator car is in motion during the first time period when the maximum value of the first summation is greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include: determining that the maximum value of the first summation is not greater than a threshold value; and determining that a door of the elevator car is not in motion during the first time period when the maximum value of the first summation is not greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the X-axis is perpendicular to a Z-axis of the elevator system, the Z-axis being parallel to a direction of travel of the elevator car.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the Y-axis is perpendicular to the X-axis and the Z-axis of the elevator system.

According to another embodiment, a system for monitoring a door of an elevator car within an elevator system is provided. The system including: a processor; and a memory including computer-executable instructions that, when executed by the processor, cause the processor to perform operations. The operations including: detecting a first plurality of accelerations along an X-axis of the elevator system during a first time period; detecting a second plurality of accelerations along a Y-axis of the elevator system during the first time period; determining an absolute value of the first plurality of accelerations; determining an absolute value of the second plurality of accelerations; determining a first summation of the absolute value of the first plurality of accelerations and the absolute value of the second plurality of accelerations; and determining whether the door of the elevator car is in motion during the first time period by determining whether a maximum value of the first summation is greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: adjusting the threshold value if the maximum value of the first summation is less than a selected value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: detecting a third plurality of accelerations along an X-axis of the elevator system during a second time period; detecting a fourth plurality of accelerations along a Y-axis of the elevator system during the second time period; determining an absolute value of the third plurality of accelerations; determining an absolute value of the fourth plurality of accelerations; determining a second summation of the absolute value of the third plurality of accelerations and the absolute value of the fourth plurality of accelerations; and determining whether the door of the elevator car is in motion during the second time period by determining whether a maximum value of the second summation is greater than the threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: determining that the door of the elevator car is in motion during the first time period and the second time period; determining that the second time period occurs at greater than threshold time period after the first time period; and determining that the door was in a reversal motion during the first time period.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: determining that the door of the elevator car is in motion during the first time period and the second time period; determining that the second time period occurs at less than threshold time period after the first time period; determining that the door was in an opening motion during the first time period; and determining that the door was in a closing motion during the first time period.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: determining that the maximum value of the first summation is greater than a threshold value; and determining that a door of the elevator car is in motion during the first time period when the maximum value of the first summation is greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the operations further include: determining that the maximum value of the first summation is not greater than a threshold value; and determining that a door of the elevator car is not in motion during the first time period when the maximum value of the first summation is not greater than a threshold value.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the X-axis is perpendicular to a Z-axis of the elevator system, the Z-axis being parallel to a direction of travel of the elevator car.

In addition to one or more of the features described herein, or as an alternative, further embodiments may include that the Y-axis is perpendicular to the X-axis and the Z-axis of the elevator system.

According to another embodiment, a computer program product embodied on a non-transitory computer readable medium is provided. The computer program product including instructions that, when executed by a processor, cause the processor to perform operations including: detecting a first plurality of accelerations along an X-axis of the elevator system during a first time period; detecting a second plurality of accelerations along a Y-axis of the elevator system during the first time period; determining an absolute value of the first plurality of accelerations; determining an absolute value of the second plurality of accelerations; determining a first summation of the absolute value of the first plurality of accelerations and the absolute value of the second plurality of accelerations; and determining whether the door of the elevator car is in motion during the first time period by determining whether a maximum value of the first summation is greater than a threshold value.

Technical effects of embodiments of the present disclosure include detecting accelerations of a door and determining movement of the door in response to the accelerations.

DETAILED DESCRIPTION

The tension member107engages the machine111, which is part of an overhead structure of the elevator system101. The machine111is configured to control movement between the elevator car103and the counterweight105. The position reference system113may be mounted on a fixed part at the top of the elevator shaft117, such as on a support or guide rail, and may be configured to provide position signals related to a position of the elevator car103within the elevator shaft117. In other embodiments, the position reference system113may be directly mounted to a moving component of the machine111, or may be located in other positions and/or configurations as known in the art. The position reference system113can be any device or mechanism for monitoring a position of an elevator car and/or counter weight, as known in the art. For example, without limitation, the position reference system113can be an encoder, sensor, or other system and can include velocity sensing, absolute position sensing, etc., as will be appreciated by those of skill in the art.

The controller115is located, as shown, in a controller room121of the elevator shaft117and is configured to control the operation of the elevator system101, and particularly the elevator car103. For example, the controller115may provide drive signals to the machine111to control the acceleration, deceleration, leveling, stopping, etc. of the elevator car103. The controller115may also be configured to receive position signals from the position reference system113or any other desired position reference device. When moving up or down within the elevator shaft117along guide rail109, the elevator car103may stop at one or more landings125as controlled by the controller115. Although shown in a controller room121, those of skill in the art will appreciate that the controller115can be located and/or configured in other locations or positions within the elevator system101. In one embodiment, the controller may be located remotely or in the cloud.

The machine111may include a motor or similar driving mechanism. In accordance with embodiments of the disclosure, the machine111is configured to include an electrically driven motor. The power supply for the motor may be any power source, including a power grid, which, in combination with other components, is supplied to the motor. The machine111may include a traction sheave that imparts force to tension member107to move the elevator car103within elevator shaft117.

Although shown and described with a roping system including tension member107, elevator systems that employ other methods and mechanisms of moving an elevator car within an elevator shaft may employ embodiments of the present disclosure. For example, embodiments may be employed in ropeless elevator systems using a linear motor to impart motion to an elevator car. Embodiments may also be employed in ropeless elevator systems using a hydraulic lift to impart motion to an elevator car.FIG.1is merely a non-limiting example presented for illustrative and explanatory purposes.

In other embodiments, the system comprises a conveyance system that moves passengers between floors and/or along a single floor. Such conveyance systems may include escalators, people movers, etc. Accordingly, embodiments described herein are not limited to elevator systems, such as that shown inFIG.1. In one example, embodiments disclosed herein may be applicable conveyance systems such as an elevator system101and a conveyance apparatus of the conveyance system such as an elevator car103of the elevator system101. In another example, embodiments disclosed herein may be applicable conveyance systems such as an escalator system and a conveyance apparatus of the conveyance system such as a moving stair of the escalator system.

Referring now toFIG.2, with continued referenced toFIG.1, a view of a sensor system200including a sensing apparatus210is illustrated, according to an embodiment of the present disclosure. The sensing apparatus210is configured to detect sensor data202of the elevator car103and transmit the sensor data202to a remote device280. Sensor data202may include but is not limited to pressure data314, vibratory signatures (i.e., vibrations over a period of time) or accelerations312and derivatives or integrals of accelerations312of the elevator car103, such as, for example, distance, velocity, jerk, jounce, snap . . . etc. Sensor data202may also include light, sound, humidity, and temperature, or any other desired data parameter. The pressure data314may include atmospheric air pressure within the elevator shaft117. It should be appreciated that, although particular systems are separately defined in the schematic block diagrams, each or any of the systems may be otherwise combined or separated via hardware and/or software. For example, the sensing apparatus210may be a single sensor or may be multiple separate sensors that are interconnected.

In an embodiment, the sensing apparatus210is configured to transmit sensor data202that is raw and unprocessed to the controller115of the elevator system101for processing. In another embodiment, the sensing apparatus210is configured to process the sensor data202prior to transmitting the sensor data202to the controller115through a processing method, such as, for example, edge processing. In another embodiment, the sensing apparatus210is configured to transmit sensor data202that is raw and unprocessed to a remote system280for processing. In yet another embodiment, the sensing apparatus210is configured to process the sensor data202prior to transmitting the sensor data202to the remote device280through a processing method, such as, for example, edge processing.

The processing of the sensor data202may reveal data, such as, for example, a number of elevator door openings/closings, elevator door time, vibrations, vibratory signatures, a number of elevator rides, elevator ride performance, elevator flight time, probable car position (e.g. elevation, floor number), releveling events, rollbacks, elevator car103x, y acceleration at a position: (i.e., rail topology), elevator car103x, y vibration signatures at a position: (i.e., rail topology), door performance at a landing number, nudging event, vandalism events, emergency stops, etc.

The remote device280may be a computing device, such as, for example, a desktop, a cloud based computer, and/or a cloud based artificial intelligence (AI) computing system. The remote device280may also be a mobile computing device that is typically carried by a person, such as, for example a smartphone, PDA, smartwatch, tablet, laptop, etc. The remote device280may also be two separate devices that are synced together, such as, for example, a cellular phone and a desktop computer synced over an internet connection.

The remote device280may be an electronic controller including a processor282and an associated memory284comprising computer-executable instructions that, when executed by the processor282, cause the processor282to perform various operations. The processor282may be, but is not limited to, a single-processor or multi-processor system of any of a wide array of possible architectures, including field programmable gate array (FPGA), central processing unit (CPU), application specific integrated circuits (ASIC), digital signal processor (DSP) or graphics processing unit (GPU) hardware arranged homogenously or heterogeneously. The memory284may be but is not limited to a random access memory (RAM), read only memory (ROM), or other electronic, optical, magnetic or any other computer readable medium.

The sensing apparatus210is configured to transmit the sensor data202to the controller115or the remote device280via short-range wireless protocols203and/or long-range wireless protocols204. Short-range wireless protocols203may include but are not limited to Bluetooth, Wi-Fi, HaLow (801.11ah), zWave, ZigBee, or Wireless M-Bus. Using short-range wireless protocols203, the sensing apparatus210is configured to transmit the sensor data202to directly to the controller115or to a local gateway device240and the local gateway device240is configured to transmit the sensor data202to the remote device280through a network250or to the controller115. The network250may be a computing network, such as, for example, a cloud computing network, cellular network, or any other computing network known to one of skill in the art. Using long-range wireless protocols204, the sensing apparatus210is configured to transmit the sensor data202to the remote device280through a network250. Long-range wireless protocols204may include but are not limited to cellular, satellite, LTE (NB-IoT, CAT M1), LoRa, Satellite, Ingenu, or SigFox.

The sensing apparatus210may be configured to detect sensor data202including acceleration in any number of directions. In an embodiment, the sensing apparatus may detect sensor data202including accelerations312along three axis, an X-axis, a Y-axis, and a Z-axis, as show in inFIG.2. The X-axis may be perpendicular to the doors104of the elevator car103, as shown inFIG.2. The Y-axis may be parallel to the doors104of the elevator car103, as shown inFIG.2. The Z-axis may be aligned vertically parallel with the elevator shaft117, the direction of travel of the elevator car103, and pull of gravity, as shown inFIG.2. The acceleration data312may reveal vibratory signatures generated along the X-axis, the Y-axis, and the Z-axis. The X-axis is perpendicular to the Y-axis and the Z-axis. The Y-axis is perpendicular to the X-axis and the Z-axis. The Z-axis is perpendicular to the X-axis and the Y-axis.

FIG.3shows a possible installation location of the sensing apparatus210within the elevator system101. The sensing apparatus210may include a magnet (not show) to removably attach to the elevator car103. In the illustrated embodiment shown inFIG.3, the sensing apparatus210may be installed on the door hanger104aand/or the door104of the elevator system101. It is understood that the sensing apparatus210may also be installed in other locations other than the door hanger104aand the door104of the elevator system101. It is also understood that multiple sensing apparatus210are illustrated inFIG.3to show various locations of the sensing apparatus210and the embodiments disclosed herein may include one or more sensing apparatus210. In another embodiment, the sensing apparatus210may be attached to a door header104eof a door104of the elevator car103. In another embodiment, the sensing apparatus210may be located on a door header104eproximate a top portion104fof the elevator car103. In another embodiment, the sensing apparatus210is installed elsewhere on the elevator car103, such as, for example, directly on the door104.

As shown inFIG.3, the sensing apparatus201may be located on the elevator car103in the selected areas106, as shown inFIG.3. The doors104are operably connected to the door header104ethrough a door hanger104alocated proximate a top portion104bof the door104. The door hanger104aincludes guide wheels104cthat allow the door104to slide open and close along a guide rail104don the door header104e. Advantageously, the door hanger104ais an easy to access area to attach the sensing apparatus210because the door hanger104ais accessible when the elevator car103is at landing125and the elevator door104is open. Thus, installation of the sensing apparatus210is possible without taking special measures to take control over the elevator car103. For example, the additional safety of an emergency door stop to hold the elevator door104open is not necessary as door104opening at landing125is a normal operation mode. The door hanger104aalso provides ample clearance for the sensing apparatus210during operation of the elevator car103, such as, for example, door104opening and closing. Due to the mounting location of the sensing apparatus210on the door hanger104a, the sensing apparatus210may detect open and close motions (i.e., acceleration) of the door104of the elevator car103and a door at the landing125. Additionally mounting the sensing apparatus210on the hanger104aallows for recording of a ride quality of the elevator car103.

FIG.4illustrates a block diagram of the sensing apparatus210of the sensing system ofFIGS.2and3. It should be appreciated that, although particular systems are separately defined in the schematic block diagram ofFIG.4, each or any of the systems may be otherwise combined or separated via hardware and/or software. As shown inFIG.4, the sensing apparatus210may include a controller212, a plurality of sensors217in communication with the controller212, a communication module220in communication with the controller212, and a power source222electrically connected to the controller212.

The plurality of sensors217includes an inertial measurement unit (IMU) sensor218configured to detect sensor data202including accelerations312of the sensing apparatus210and the elevator car103when the sensing apparatus210is attached to the elevator car103. The IMU sensor218may be a sensor, such as, for example, an accelerometer, a gyroscope, or a similar sensor known to one of skill in the art. The accelerations312detected by the IMU sensor218may include accelerations312as well as derivatives or integrals of accelerations, such as, for example, velocity, jerk, jounce, snap . . . etc. The IMU sensor218is in communication with the controller212of the sensing apparatus210.

The plurality of sensors217includes a pressure sensor228is configured to detect sensor data202including pressure data314, such as, for example, atmospheric air pressure within the elevator shaft117. The pressure sensor228may be a pressure altimeter or barometric altimeter in two non-limiting examples. The pressure sensor228is in communication with the controller212.

The plurality of sensors217may also include additional sensors including but not limited to a light sensor226, a pressure sensor228, a microphone230, a humidity sensor232, and a temperature sensor234. The light sensor226is configured to detect sensor data202including light exposure. The light sensor226is in communication with the controller212. The microphone230is configured to detect sensor data202including audible sound and sound levels. The microphone230is in communication with the controller212. The humidity sensor232is configured to detect sensor data202including humidity levels. The humidity sensor232is in communication with the controller212. The temperature sensor234is configured to detect sensor data202including temperature levels. The temperature sensor234is in communication with the controller212.

The controller212of the sensing apparatus210includes a processor214and an associated memory216comprising computer-executable instructions that, when executed by the processor214, cause the processor214to perform various operations, such as, for example, edge pre-processing or processing the sensor data202collected by the IMU sensor218, the light sensor226, the pressure sensor228, the microphone230, the humidity sensor232, and the temperature sensor234. In an embodiment, the controller212may process the accelerations312and/or the pressure data314in order to determine a probable location of the elevator car103, discussed further below. The processor214may be but is not limited to a single-processor or multi-processor system of any of a wide array of possible architectures, including field programmable gate array (FPGA), central processing unit (CPU), application specific integrated circuits (ASIC), digital signal processor (DSP) or graphics processing unit (GPU) hardware arranged homogenously or heterogeneously. The memory216may be a storage device, such as, for example, a random access memory (RAM), read only memory (ROM), or other electronic, optical, magnetic or any other computer readable medium.

The power source222of the sensing apparatus210is configured to store and supply electrical power to the sensing apparatus210. The power source222may include an energy storage system, such as, for example, a battery system, capacitor, or other energy storage system known to one of skill in the art. The power source222may also generate electrical power for the sensing apparatus210. The power source222may also include an energy generation or electricity harvesting system, such as, for example synchronous generator, induction generator, or other type of electrical generator known to one of skill in the art.

The sensing apparatus210includes a communication module220configured to allow the controller212of the sensing apparatus210to communicate with the remote device280and/or controller115through at least one of short-range wireless protocols203and long-range wireless protocols204. The communication module220may be configured to communicate with the remote device280using short-range wireless protocols203, such as, for example, Bluetooth, Wi-Fi, HaLow (801.11ah), Wireless M-Bus, zWave, ZigBee, or other short-range wireless protocol known to one of skill in the art. Using short-range wireless protocols203, the communication module220is configured to transmit the sensor data202to a local gateway device240and the local gateway device240is configured to transmit the sensor data202to a remote device280through a network250, as described above. The communication module220may be configured to communicate with the remote device280using long-range wireless protocols204, such as for example, cellular, LTE (NB-IoT, CAT M1), LoRa, Ingenu, SigFox, Satellite, or other long-range wireless protocol known to one of skill in the art. Using long-range wireless protocols204, the communication module220is configured to transmit the sensor data202to a remote device280through a network250. In an embodiment, the short-range wireless protocol203is sub GHz Wireless M-Bus. In another embodiment, the long-range wireless protocol is SigFox. In another embodiment, the long-range wireless protocol is LTE NB-IoT or CAT M1 with 2G fallback.

The sensing apparatus210includes a location determination module330configured to determine a location (i.e., position) of the elevator car103within the elevator shaft117. The location of the elevator car103may be fixed locations along the elevator shaft117, such as for example, the landings125of the elevator shaft117. The locations may be equidistantly spaced apart along the elevator shaft117such as, for example, 5 meters or any other selected distance. Alternatively, the locations may be or intermittently spaced apart along the elevator shaft117.

The location determination module330may utilize various approaches to determine a location of the elevator car103within the elevator shaft117. The location determination module330may be configured to determine a location of the elevator car103within the elevator shaft117using at least one of a pressure location determination module310and an acceleration location determination module320.

The acceleration location determination module320is configured to determine a distance traveled of the elevator car103within the elevator shaft117in response to the acceleration of the elevator car103detected along the Y axis. The sensing apparatus210may detect an acceleration along the Y axis shown at322and may integrate the acceleration to get a velocity of the elevator car103at324. At326, the sensing apparatus210may also integrate the velocity of the elevator car103to determine a distance traveled by the elevator car103within the elevator shaft117during the acceleration312detected at322. The direction of travel of the elevator car103may also be determined in response to the acceleration312detected. The location determination module330may then determine the location of the elevator car103within the elevator shaft117in response to a starting location and a distance traveled away from that starting location. The starting location may be based upon tracking the past operation and/or movement of the elevator car103.

The pressure location determination module310is configured to detect an atmospheric air pressure within the elevator shaft117when the elevator car103is in motion and/or stationary using the pressure sensor228. The pressure detected by the pressure sensor228may be associated with a location (e.g., height, elevation) within the elevator shaft117through either a look up table or a calculation of altitude using the barometric pressure change in two non-limiting embodiments. The direction of travel of the elevator car103may also be determined in response to the change in pressure detected via the pressure data314. The pressure sensor228may need to periodically detect a baseline pressure to account for changes in atmospheric pressure due to local weather conditions. For example, this baseline pressure may need to be detected daily, hourly, or weekly in non-limiting embodiments. In some embodiments, the baseline pressure may be detected whenever the elevator car103is stationary, or at certain intervals when the elevator car103is stationary and/or at a known location. The acceleration of the elevator car103may also need to be detected to know when the elevator car103is stationary and then when the elevator car103is stationary the sensing apparatus210may need to be offset to compensate the sensor drift and environment drift.

In one embodiment, the pressure location determination module310may be used to verify and/or modify a location of the elevator car102within the elevator shaft117determined by the acceleration location determination module320. In another embodiment, the acceleration location determination module320may be used to verify and/or modify a location of the elevator car102within the elevator shaft117determined by the pressure location determination module310. In another embodiment, the pressure location determination module310may be prompted to determine a location of the elevator car103within the elevator shaft117in response to an acceleration detected by the IMU sensor218.

Referring now toFIGS.5and6, while referencing components ofFIGS.1-4.FIG.5shows a flow chart of a method500of monitoring a door104of an elevator car103within an elevator system101, in accordance with an embodiment of the disclosure. In an embodiment, the method500may be performed by at least one of the sensing apparatus210, the controller115, and the remote device280.FIG.6illustrates analysis of detected accelerations312of the elevator system101over time601within a chart600.

At block504, a first plurality of accelerations602is detected along an X-axis of the elevator system101during a first time period610. In an embodiment, X-axis is perpendicular to a Z-axis of the elevator system101and the Z-axis is parallel to a direction of travel of the elevator car103. At block506, a second plurality of accelerations604is along a Y-axis of the elevator system101during the first time period610. In an embodiment, the Y-axis is perpendicular to the X-axis and the Z-axis of the elevator system101.

At block508, an absolute value of the first plurality of accelerations is determined. At block510, an absolute value of the second plurality of accelerations604is determined.

At block511, the absolute value of the first plurality of accelerations602is combined with the absolute value of the second plurality of accelerations604and a first summation630adetermined. The first summation630aof the absolute value of the first plurality of accelerations602and the absolute value of the second plurality of accelerations604may be visible on the chart600illustrated inFIG.6.

At block512, it is determined whether a door104of the elevator car103is in motion during the first time period610by determining whether a maximum value632aof the first summation630ais greater than a threshold value640.

At block512, the method500may utilize equation (i):
IF MAX[t2-t1](ABS(accx(t)))+(ABS(accy(t)))>Threshold Value THEN door movement=TRUE  (i)

Where the t2-t1is the first time period610, MAX[t2-t1] is the maximum value during the first time period610of the first summation630aof (ABS(accx(t)))+(ABS(accy(t))), ABS(accx(t)) is the absolute value of the first plurality of accelerations602along the X-axis during the first time period610, ABS(accy(t)) is the absolute value of the second plurality of accelerations604along the Y-axis during the first time period610.

If at block512it is determined that the maximum value632aof the first summation630ais greater than a threshold value640then at block514it is determined that the door104of the elevator car103is in motion during the first time period when the maximum value632aof the first summation630ais greater than a threshold value640. Equation i may generate a square function650at a value of one when the elevator door104is confirmed to be moving.

If at block512it is determined that the maximum value632aof the first summation630ais not greater than a threshold value640then at block514it is determined that the door104of the elevator car103is not in motion during the first time period when the maximum value632aof the first summation630ais not greater than a threshold value640.

The method500may further include adjusting the threshold value640if the maximum value632aof the first summation630ais less than a selected value, which may be represented by equation ii.
IF MAX[t2-t1](ABS(accx(t)))+(ABS(accy(t)))<Selected Value THEN Threshold value=X1
ELSE Threshold value=X2*(MAX[t2-t1](ABS(accx(t)))+(ABS(accy(t)))  (ii)

Where X1 is a first variable and X2 is a second variable. The first variable is a base value, which allows detection of door movement for doors104with low vibrations or accelerations312(e.g. center opening doors). To ensure edge computing on the sensing apparatus210is ready to detect door104movements with higher accelerations312then the threshold value needs to be adjusted, which may be accomplished by measuring the max acceleration values during door104movement and adjusting the threshold accordingly with the second variable. In an embodiment, the first variable X1 may be equivalent to less than 300 mg. In an embodiment, the second variable may be equivalent to about (20+7/30).

The method500may further include: detecting a third plurality of accelerations606along an X-axis of the elevator system101during a second time period620and detecting a fourth plurality of accelerations608along a Y-axis of the elevator system101during the second time period620. The method500may also include that an absolute value of the third plurality of accelerations606and an absolute value of the fourth plurality of accelerations608are determined.

A second summation630bmay be determined. The second summation630bis the summation of the absolute value of the third plurality of accelerations606and the absolute value of the fourth plurality of accelerations608may be visible on the chart600illustrated inFIG.6.

It may then be determined whether the door104of the elevator car103is in motion during the second time period620by determining whether a maximum value632bof the second summation630bis greater than a threshold value640, which may utilize equation iii
IF MAX[t4-t3](ABS(accx(t)))+(ABS(accy(t)))>Threshold Value THEN door movement=TRUE  (i)

Where the t4-t3is the second time period620, MAX[t2-t1] is the maximum value632bduring the first time period610of the second summation630bof (ABS(accx(t)))+(ABS(accy(t))), ABS(accx(t)) is the absolute value of the third plurality of accelerations606along the X-axis during the second time period620, ABS(accy(t)) is the absolute value of the fourth plurality of accelerations608along the Y-axis during the second time period620.

If it is determined that the door104of the elevator car103is in motion during the first time period610and the second time period620and that the second time period620occurs at greater than threshold time period after the first time period610then it may be determined that the door was in a reversal motion during the first time period610. For example, if the door motion is detected during the first time period610but then door motion is not detected moving until the next day during the second time period620then it may be determined that the door motion during the first time period610and the second time period620are not connected9(e.g., not an opening and closing pair)

If it is determined that the door104of the elevator car103is in motion during the first time period610and the second time period620and that the second time period620occurs at less than a threshold time period after the first time period610then it may be determined that the door103was in an opening motion during the first time period610and the door104was in a closing motion during the second time period620. For example, if the door motion is detected moving during the first time period610and then a short time later door motion is detected during the second time period then it may be determined that the motion during the first time period610and the second time period620are connected and the door motion during the first time period610may be an opening motion of the door104and the door motion during the second time period620may be a closing motion of the door104complimenting the opening motion.

While the above description has described the flow process ofFIG.5in a particular order, it should be appreciated that unless otherwise specifically required in the attached claims that the ordering of the steps may be varied.

The term “about” is intended to include the degree of error associated with measurement of the particular quantity and/or manufacturing tolerances based upon the equipment available at the time of filing the application.