Multi-level detection trigger for human sensing

Abstract

An elevator system has an elevator car, a hoistway, and a pit; a sensor assembly, the sensor assembly comprising a sensor, the sensor configured to capture and process an image; an elevator safety chain; wherein the sensor assembly is configured to: monitor in a first sensing mode to detect whether an object is located in a first area of the elevator system; after the object is detected in the first area in the first sensing mode, monitoring in a second sensing mode more sensitive than the first sensing mode to detect the object in the second sensitivity mode; and opening, by the sensor assembly, the elevator safety chain to stop the elevator car when the object is detected in the second sensitivity mode.

Description

Technical Field

[0001] Embodiments herein relate to elevator safety systems, and more particularly to multi-level detection triggering for human sensing. Background Art

[0002] A potentially dangerous condition may exist in the hoistway due to a failure to gain and maintain control of the car or counterweight. Therefore, human sensing devices that open the elevator safety chain (e.g., cut drive power and engage machine brakes) may be installed in the hoistway and on top of the car to make the system foolproof. However, to be effective, these devices should be configured to avoid false positives while maintaining sufficient sensitivity to avoid false negatives. Summary of the invention Disclosed is an elevator system comprising: an elevator car, a hoistway, and a pit; a sensor assembly configured to capture and process images; an elevator safety chain; wherein the sensor assembly is configured to: monitor in a first sensing mode to detect whether an object that may be a human being is located in a first area of ​​the elevator system; after detecting the object in the first area in the first sensing mode, monitor in a second sensing mode that is more sensitive than the first sensing mode to detect the object in the second sensitivity mode; and when the object is detected in the second sensitivity mode, open the elevator safety chain by the sensor assembly to stop the elevator car. Additionally or alternatively, the sensor assembly is mounted to the elevator car, the elevator car includes a roof, and the first region is the roof of the elevator car. Additionally or alternatively to one or more aspects of the disclosed system, the sensor is a motion, depth, or distance sensor. Additionally or alternatively in addition to one or more aspects of the disclosed system, the sensor is one of a LIDAR, a RADAR, or a camera. Additionally or alternatively in addition to one or more aspects of the disclosed system, the sensor is a millimeter wave RADAR or RGBD camera. In addition to or as an alternative to one or more aspects of the disclosed system, in the first sensing mode, the sensor captures images at a first frame rate and at a first spatial resolution; and in the second sensing mode, the sensor captures images at a second frame rate higher than the first frame rate and at a second spatial resolution higher than the first spatial resolution. Additionally or alternatively to one or more aspects of the disclosed system, in the second sensitivity mode, the sensing component focuses on an area or spatial volume that includes an image of the object in the first sensitivity mode. In addition to or as an alternative to one or more aspects of the disclosed system, in the first sensing mode, the sensor component detects the object in the data stream when the size of the object is above a first threshold; and in the second sensing mode, the sensor component detects the object in the data stream from predetermined image features and it is present in a number of image frames above a threshold. In addition to or as an alternative to one or more aspects of the disclosed system, the system includes a plurality of sensors, including sensors distributed around the top of the elevator car, and wherein, when the sensors capture image data including the object, the sensor assembly: instructs each of the plurality of sensors to operate in the second sensing mode; or instructs only the sensors to operate in the second sensing mode. Additionally or alternatively, upon entering the second sensing mode, the sensor assembly executes a countdown timer and returns to the first sensing mode upon failure to detect the object in the second sensing mode before expiration of the timer. Also disclosed is a method for controlling an elevator system having an elevator car, a hoistway, and a pit, the method comprising: in a first sensing mode, monitoring using a sensor assembly including a sensor and configured to capture and process images to detect whether an object that may be a human being is located in a first area of ​​the elevator system; after detecting the object in the first area in the first sensing mode, monitoring using the sensor assembly in a second sensing mode that is more sensitive than the first sensing mode to detect the object in the second sensing mode; and when the object is detected in the second sensing mode, opening an elevator safety chain to stop the elevator car. Additionally or alternatively to one or more aspects of the disclosed method, the sensor assembly is mounted to the elevator car, the elevator car includes a roof, and the first region is the roof of the elevator car. Additionally or alternatively to one or more aspects of the disclosed method, the sensor is a motion, depth or distance sensor. Additionally or alternatively to one or more aspects of the disclosed method, the sensor is one of a LIDAR, a RADAR, or a camera. Additionally or alternatively to one or more aspects of the disclosed method, the sensor is a millimeter wave RADAR or RGBD camera. In addition to or as an alternative to one or more aspects of the disclosed method, in the first sensing mode, the sensor captures images at a first frame rate and at a first spatial resolution; and in the second sensing mode, the sensor captures images at a second frame rate higher than the first frame rate and at a second spatial resolution higher than the first spatial resolution. Additionally or alternatively to one or more aspects of the disclosed method, in the second sensitivity mode, the sensing component focuses on an area or spatial volume that includes the image of the object in the first sensitivity mode. In addition to or as an alternative to one or more aspects of the disclosed method, in the first sensing mode, the sensor component detects the object in the data stream when the size of the object is above a first threshold; and in the second sensing mode, the sensor component detects the object in the data stream from predetermined image features and it is present in a number of image frames above a threshold. In addition to or as an alternative to one or more aspects of the disclosed method, a plurality of sensors comprising the sensor are distributed around the top of the elevator car, and wherein, when the sensor captures image data including the object, the sensor assembly: instructs each of the plurality of sensors to operate in the second sensing mode; or instructs only the sensor to operate in the second sensing mode. In addition to or as an alternative to one or more aspects of the disclosed method, upon entering the second sensing mode, the sensor assembly executes a countdown timer and returns to the first sensing mode when the object is not detected in the second sensing mode before the timer expires. Unless otherwise expressly indicated, the foregoing features and elements may be combined into various combinations without exclusivity. These features and elements and their operation will become more clear in view of the following description and drawings. However, it should be understood that the following description and drawings are intended to be illustrative and explanatory in nature, rather than limiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present disclosure is illustrated by way of example and not limitation, in the accompanying figures, in which like references indicate similar elements.

[0025] Figure 1 is a schematic illustration of an elevator system in which various embodiments of the present disclosure may be employed;

[0026] Figure 2 Additional aspects of an elevator system are shown that is configured with a plurality of motion sensors for detecting an object that may be a human being on top of an elevator car;

[0027] Figure 3is a flow chart of a process performed by an elevator system for detecting an object on top of an elevator car and responsively controlling the elevator car; and

[0028] Figure 4 is a flow chart generally illustrating a process performed by an elevator system for detecting an object on top of an elevator car and responsively controlling the elevator car. DETAILED DESCRIPTION

[0029] Figure 1 1 is a perspective view of an elevator system 101, which includes an elevator car 103, a counterweight 105, a tension member 107, a guide rail 109, a machine 111 (alternatively referred to as a drive), a position reference system 113, and a system controller 115 that can be used to control normal elevator car operations and active safety functions. The elevator car 103 and the counterweight 105 are connected to each other through the tension member 107. The tension member 107 can include or be configured as, for example, a rope, a steel cable, and / or a coated steel belt. The counterweight 105 is configured to balance the load of the elevator car 103 and is configured to facilitate the movement of the elevator car 103 in an elevator shaft or hoistway 117 and along the guide rail 109 in a direction opposite to the counterweight 105.

[0030] The tension member 107 engages a machine 111, which is part of the overhead structure of the elevator system 101. The machine 111 is configured to control the movement between the elevator car 103 and the counterweight 105. The position reference system 113 can be mounted on a fixed portion of the top of the elevator shaft 117, such as on a support or rail, and can be configured to provide a position signal related to the position of the elevator car 103 within the elevator shaft 117. In other embodiments, the position reference system 113 can be mounted directly to the moving parts of the machine 111, or can be located in other positions and / or configurations as known in the art. The position reference system 113 can be any device or mechanism for monitoring the position of the elevator car and / or counterweight as known in the art. For example, and not limitation, the position reference system 113 can be an encoder, a sensor, or other system, and can include speed sensing, absolute position sensing, etc., as will be appreciated by those skilled in the art.

[0031] As shown, the system controller 115 is located in a controller room 121 of the elevator shaft 117 and is configured to control the operation of the elevator system 101, particularly the elevator car 103. It is to be appreciated that the controller 115 need not be in the controller room 121, but may be in the hoistway or other locations in the elevator system. For example, the system controller 115 may provide drive signals to the machine 111 to control the acceleration, deceleration, leveling, stopping, etc. of the elevator car 103. The system controller 115 may also be configured to receive position signals from the position reference system 113 or any other desired position reference device. When moving up or down along the guide rails 109 in the elevator shaft 117, the elevator car 103 may stop at one or more landings 125 under the control of the system controller 115. Although shown in the controller room 121, those skilled in the art will appreciate that the system controller 115 may be located and / or configured elsewhere or at locations within the elevator system 101. In one embodiment, the system controller 115 may be located remotely or in a distributed computing network (e.g., a cloud computing architecture). System controller 115 may be implemented using a processor-based machine such as a personal computer, server, distributed computing network, or the like.

[0032] The machine 111 may include a motor or similar drive mechanism. According to an embodiment of the present disclosure, the machine 111 is configured to include an electrically driven motor. The power supply for the motor may be any power source (including the power grid), and the power supply is supplied to the motor in combination with other components. The machine 111 may include a traction sheave that transmits force to the tension member 107 to move the elevator car 103 within the elevator shaft 117.

[0033] The elevator system 101 also includes one or more elevator doors 104. The elevator doors 104 may be attached to the elevator car 103, or the elevator doors 104 may be located on a landing 125 of the elevator system 101, or both. The embodiments disclosed herein may be applicable to elevator doors 104 attached to the elevator car 103 or elevator doors 104 located on a landing 125 of the elevator system 101, or both. The elevator doors 104 open to allow passengers to enter and exit the elevator car 103.

[0034] like Figure 2As shown in FIG. 1 , an elevator car 103 in a hoistway 117 has a sensor assembly 150, which may include one or more sensors 140, and may further include or communicate with a processor 145, and the processor 145 may capture and process an image 142. The sensor assembly 150 has a memory and a communication circuit so that it communicates to, for example, a system controller 115 via an intelligent safety control system. The sensor assembly 150 may include a link to a controllable relay that can be opened to open a safety chain. The connection to the safety chain may be via a relay or via a message transmitted to an elevator safety system (including a system controller 115) via an intelligent safety control system.

[0035] The car top 130 may be equipped with sensors 140, including a first sensor 140a, operatively coupled to a processor 145. It is to be appreciated that other mounting configurations in the elevator system are within the scope of the present disclosure. The sensor 140 may be a motion sensor. The sensor 140, which may be a distance or depth sensor, may be a LIDAR, a RADAR such as a millimeter wave RADAR, or a camera such as an RGBD camera. The sensor assembly 150 is configured to sense when an object of interest 155, whose size and motion indicate that it may be a human, is above the elevator car 103 and to open the elevator safety chain, resulting in the cutting of the driving force from the machine 111 and the engagement of the machine brake 160. Alternatively, the sensor assembly 150 may be mounted elsewhere on the elevator car (such as at the bottom) or elsewhere on the elevator system (such as within the hoistway, pit, including pit ladders). Go to Figure 3 , which flowchart illustrates the operation of the system 101 when an object 155 is detected on the roof 130 of the car, such as a ventilation grille. As shown in block 300, the sensor assembly 150 monitors the roof 130 of the car 103 for an object 155 in a first sensitivity mode. It is to be appreciated that the concept of different sensitivities applies to a range of virtual safety nets (VSNs) or sensor assemblies 150.

[0040] The first sensitivity mode is a relatively low sensitivity mode. In the first sensitivity mode, the sensor 140 is configured to capture images 142 at a relatively low first frame rate and at a relatively low first spatial resolution. In addition, the sensor assembly 150 is configured such that when analyzing the data stream 142, the first object size threshold is set to a larger setting and the first duration threshold is relatively short.

[0041] Thus, if object 155 located on top 130 of elevator car 103 is relatively large, sensor assembly 150 will detect object 155. However, the presence of object 155 need only be captured in a relatively small number of image frames.

[0042] When no object 155 is detected on the car roof 130 ("No" at block 310), the sensor assembly 150 will continue to monitor at the first sensitivity level. If the sensor data stream 142 includes an object 155 during this activity ("Yes" at block 310), the sensor assembly 150 will monitor in the second sensitivity mode as shown in block 320.

[0043] The second sensitivity mode is a higher sensitivity mode than the first sensitivity mode. In the second sensitivity mode, the sensor 140 is configured to capture the image 142 at a second frame rate higher than the first frame rate and at a second spatial resolution higher than the first spatial resolution. In addition, the sensor assembly 150 is configured so that when analyzing the data stream 142, the second object size threshold is set at a setting smaller than the first object size threshold, and the second persistence threshold is longer than the first persistence threshold. Sensitivity mode factors (such as frame rate and spatial resolution) can also include an area or volume of interest in a scan area or plane, wherein the second sensitivity is used only in the area that passed the first detection gate 310.

[0044] Thus, in the second sensitivity mode, the sensor assembly 150 will detect the object 155 based on, for example, that the object 155 has predetermined image features associated with the object 155 that are similar to a human (e.g., other than or in addition to its size), and that it is present in a relatively larger number of image frames, e.g., above a threshold. Such features may include its motion, its appendages such as arms, legs, torso, head, their size, and relative motion to each other and to the elevator car. Other features, such as the presence of personal equipment including a hard hat and carried equipment, may also result in the detection of the object. The benefit of this two-level sensitivity approach is that the increased resolution of the second sensitivity mode in both temporal and spatial coordinates may also reduce the number of false positive results (i.e., when the sensor assembly 150 says there is a person, but in fact there is no person and the elevator operation is terminated).

[0045] When analyzing the object 155 in the data stream 142 in the second sensitivity mode, if the sensor assembly 150 cannot detect the object 155 within a time period greater than the threshold ("No" at block 330), the sensor assembly resets the sensitivity to the first sensitivity mode (block 300) at block 340. Such a process may include the sensor assembly 150 executing a countdown timer and returning to the first sensing mode when the object is not detected in the second sensing mode before the timer expires. Otherwise, if the sensor assembly 150 is able to detect the object 155 in the second sensing mode ("Yes" at block 330), the safety chain is opened at block 350 to stop the machine 111 and engage the machine brake 160. Then at block 360, the sensor assembly 150 determines to reset the safety chain, for example, by the action of a maintenance crew member. The sensor assembly 150 will then return to the first sensitivity mode and continue from block 300 as indicated above.

[0050] Figure 4 4 is a flow chart generally illustrating a process performed by the elevator system 101 for detecting an object 155 on the top 130 of the elevator car 103 and responsively controlling (e.g., stopping) the elevator car 103. As shown in block 410, the method includes monitoring in a first sensing mode with a sensor assembly 150 mounted to the elevator car 103 and operably coupled to the system controller 115 to detect whether the object 155 is located in a first area 127 of the elevator system 101, the first area 127 being outside the elevator car 103. As shown in block 420, the method includes, after detecting the object 155 in the first area 127 in the first sensing mode, monitoring in a second sensing mode that is more sensitive than the first sensing mode with the sensor assembly 150 to detect the object 155 in the second sensing mode. As shown in block 430, the method includes, when the object 155 is detected in the second sensing mode, opening the elevator safety chain to stop the elevator car 103, which includes controlling the drive 111 and the machine brake 160 to stop the elevator car 103.

[0053] In one embodiment, sensors 140 are distributed around a first area 127 outside of elevator car 103, and in one embodiment, first area 127 is top 130 of elevator car 103. The disclosed detection process can be applied to other areas of elevator system 101 such as pit areas, ladders, etc.

[0054] If only the first sensor 140a captures an image indicating the object 155, the sensor assembly 150 may cause each of the sensors 140 to operate in the second sensing mode. Alternatively, to save resources, the sensor assembly 150 causes only the first sensor 140a to operate in the second sensing mode.

[0055] In the disclosed embodiment, the object 155 must be detected in one or both sensing modes before the elevator car 103 stops. The disclosed embodiment minimizes situations in which the sensor assembly 150 erroneously detects a human being on top of the elevator car (i.e., otherwise referred to as a false positive), which may be caused by potentially detected events in the hoistway (including, for example, counterweight movement, swaying traveling cables, rodents, reflections, debris, dust). As indicated, the disclosed system normally operates in a first sensitivity mode, with a lower sensitivity setting, utilizing a lower frame rate, lower spatial resolution, a larger object size threshold, and a short duration threshold. When an object exceeding the first threshold has been detected, the setting transitions to a second sensitivity mode, which is a higher sensitivity mode, with a higher frame rate, higher spatial resolution, a smaller object size threshold, and a longer duration threshold.

[0057] It is within the scope of the embodiments to use a convolutional neural network (CNN) trained to recognize human shapes and movements. During the second sensitivity mode, the application of the CNN detects the presence of humans and then opens the safety chain. Similarly, machine learning, artificial intelligence, and other tools and methods for data analysis can be utilized. Sensing humans includes detecting fragments, limbs, and fingers or toes, not necessarily the entire person. Depending on the sensing modality used and the well application area, it is possible that the system will not detect the entire human shape.

[0058] The sensor data identified herein may be acquired and processed separately, or acquired and processed simultaneously and stitched together, or a combination thereof, and may be processed in raw or compiled form. The sensor data may be processed at the sensor (e.g., via edge computing), by a controller identified or implied herein, on a cloud service, or by a combination of one or more of these computing systems. The sensor may transmit data via a wired or wireless transmission line, applying one or more protocols as indicated below.

[0059] Wireless connection can apply the protocol including local area network (LAN, or WLAN for wireless LAN) protocol. LAN protocol includes WiFi technology based on the standard of Section 802.11 of the Institute of Electrical and Electronics Engineers (IEEE). Other applicable protocols include low power WAN (LPWAN), which is a wireless wide area network (WAN) designed to allow remote communication at low bit rates so that the final device can operate in an extended period (several years) using battery power. Long-range WAN (LoRaWAN) is a type of LPWAN maintained by the LoRa Alliance, and is a media access control (MAC) layer protocol for transmitting management and application messages between a network server and an application server, respectively. LAN and WAN protocols can generally be regarded as TCP / IP protocols (Transmission Control Protocol / Internet Protocol), which are used to manage the connection of computer systems to the Internet. Wireless connection can also apply the protocol including private area network (PAN) protocol. PAN protocol includes, for example, Bluetooth Low Energy (BTLE), which is a wireless technology standard designed and sold by the Bluetooth Special Interest Group (SIG) for exchanging data across short distances using short wavelength radio waves. PAN protocols also include Zigbee, a technology based on the Section 802.15.4 protocol from the IEEE, which represents a set of advanced communication protocols for creating personal area networks with small, low-power digital radios for low-power, low-bandwidth requirements. Such protocols also include Z-Wave, a wireless communication protocol supported by the Z-Wave Alliance that uses mesh networking to apply low-energy radio waves to communicate between devices such as appliances, allowing wireless control of the devices.

[0060] The wireless connection may also include radio frequency identification (RFID) technology, which is used to communicate with an integrated chip (IC) on, for example, an RFID smart card. In addition, sub-1Ghz RF devices operate in the ISM (industrial, scientific and medical) spectrum band below sub-1Ghz, typically in the frequency ranges of 769–935MHz, 315Mhz and 468Mhz. This spectrum band below 1Ghz is particularly useful for RF IOT (Internet of Things) applications. The Internet of Things (IoT) describes a network of physical objects—"things"—embedded with sensors, software and other technologies, for connecting and exchanging data with other devices and systems over the Internet. Other LPWAN-IOT technologies include narrowband Internet of Things (NB-IOT) and category M1 Internet of Things (Cat M1-IOT). The wireless communication of the disclosed system may include cellular, such as 2G / 3G / 4G (etc.). Other wireless platforms based on RFID technology include near field communication (NFC), which is a set of communication protocols for low-speed communication, for example, for exchanging data between electronic devices across short distances. NFC standards are defined by the ISO / IEC (defined below), the NFC Forum and the GSMA (Global System for Mobile Communications) groups.The above is not intended to limit the scope of applicable wireless technologies.

[0061] Wired connections may include connections (cables / interfaces) under RS ​​(Recommended Standard)-422, also known as TIA / EIA-422, which is a technical standard supported by the Telecommunications Industry Association (TIA) and initiated by the Electronic Industries Alliance (EIA) that specifies the electrical characteristics of digital signaling circuits. Wired connections may also include connections (cables / interfaces) under the RS-232 standard for serial communication transmission of data, which formally defines the signals connected between DTE (data terminal equipment) such as computer terminals and DCE (data circuit-terminating equipment or data communications equipment) such as modems. Wired connections may also include connections (cables / interfaces) under the Modbus serial communication protocol managed by the Modbus organization. Modbus is a master / slave protocol designed for use with its programmable logic controller (PLC), and it is a commonly available means of connecting industrial electronic devices. Wireless connections may also include connectors (cables / interfaces) under the PROFibus (process field bus) standard managed by PROFIBUS & PROFINET International (PI). PROFibus is a standard for fieldbus communication in automation technology and is published as part of IEC (International Electrotechnical Commission) 61158. Wired communication is also possible via the Controller Area Network (CAN) bus. CAN is a vehicle bus standard that allows microcontrollers and devices to communicate with each other in applications without a host computer. CAN is a message-based protocol published by the International Standards Organization (ISO). The above is not intended to limit the scope of applicable wired technologies.

[0062] When data is transmitted over a network between final processors as identified herein, the data may be transmitted in raw form, or may be processed in whole or in part in any of the final processors or intermediate processors, such as in a cloud service (e.g., where at least a portion of the transmission path is wireless) or other processors. The data may be parsed, partially or completely processed or compiled in any of the processors, and then may be spliced ​​together or maintained as separate information packets. Each processor or controller identified herein may be, but is not limited to, a single processor or multi-processor system of any architecture in a variety of possible architectures, including field programmable gate arrays (FPGAs), central processing units (CPUs), application specific integrated circuits (ASICs), digital signal processors (DSPs), or graphics processing units (GPUs) hardware arranged homogeneously or heterogeneously. The memory identified herein may be, but is not limited to, random access memory (RAM), read-only memory (ROM), or other electronic, optical, magnetic, or any other computer-readable medium.

[0063] In addition to the processor and non-volatile memory, the controller may further include one or more input and / or output (I / O) device interfaces, which are coupled in communication via an onboard (local) interface to communicate between other devices. The onboard interface may include, for example, but not limited to, an onboard system bus, including a control bus (for inter-device communication), an address bus (for physical addressing), and a data bus (for transmitting data). That is, the system bus can realize electronic communication between the processor, the memory, and the I / O connection. The I / O connection may also include a wired connection and / or a wireless connection identified herein. The onboard interface may have additional elements omitted for simplicity, such as a controller, a buffer (cache), a driver, a repeater, and a receiver to realize electronic communication. The memory may execute a program, access data or a lookup table, or a combination of each item to facilitate its processing, all of which may be pre-stored or received by other computing devices during the execution of its process, for example, via a cloud service or other network connections with other processors identified herein.

[0064] Embodiments may take the form of processor-implemented processes and means (such as a processor) for practicing those processes. Embodiments may also take the form of computer code-based modules, such as computer program code (e.g., computer program products) containing instructions embodied in tangible media (e.g., non-transitory computer-readable media), such as floppy disks, CD ROMs, hard drives, processor registers (such as firmware), or any other non-transitory computer-readable media, wherein when the computer program code is loaded into a computer and executed by the computer, the computer becomes a means for practicing the embodiments. Embodiments may also take the form of computer program code, such as whether stored in a storage medium, loaded into a computer and / or executed by a computer, or transmitted through some transmission medium (such as by wire or cable, by optical fiber, or via electromagnetic radiation), wherein when the computer program code is loaded into a computer and executed by a computer, the computer becomes a means for practicing the exemplary embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.

[0065] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "a", and "the" are intended to include the plural forms as well. It will be further understood that the terms "include" and / or "comprise" when used in this specification specify the presence of the features, integers, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups thereof.

[0066] Those skilled in the art will appreciate that various example embodiments are shown and described herein, all with certain features in specific embodiments, but the present disclosure is not limited thereby. On the contrary, the present disclosure may be modified to incorporate any number of variations, changes, substitutions, combinations, sub-combinations, or equivalent arrangements not previously described but commensurate with the scope of the present disclosure. In addition, although various embodiments of the present disclosure have been described, it is to be understood that aspects of the present disclosure may include only some of the described embodiments. Therefore, the present disclosure is not to be considered limited by the foregoing description, but only by the scope of the appended claims.

Claims

1. An elevator system, comprising: Elevator cars, hoistways, and pits; a sensor assembly configured to capture and process images; Elevator safety chains; Wherein, the sensor assembly is configured as follows: monitoring in a first sensing mode to detect whether an object that may be a human is located in a first zone of the elevator system; After detecting the object in the first area in the first sensing mode, monitoring in a second sensing mode that is more sensitive than the first sensing mode to detect the object in the second sensitivity mode; as well as When the object is detected in the second sensitivity mode, the elevator safety chain is opened by the sensor assembly to stop the elevator car.

2. The system according to claim 1, wherein: The sensor assembly is mounted to the elevator car, the elevator car includes a roof, and the first region is the roof of the elevator car.

3. The system according to claim 1, wherein: The sensor is a motion, depth or distance sensor.

4. The system according to claim 1, wherein: The sensor is one of LIDAR, RADAR or a camera.

5. The system according to claim 1, wherein: The sensor is a millimeter wave RADAR or an RGBD camera.

6. The system of claim 1, wherein: In the first sensing mode, the sensor captures images at a first frame rate and at a first spatial resolution; as well as In the second sensing mode, the sensor captures images at a second frame rate higher than the first frame rate and at a second spatial resolution higher than the first spatial resolution.

7. The system according to claim 6, wherein: In the second sensitivity mode, the sensing component focuses on an area or spatial volume that includes the image of the object in the first sensitivity mode.

8. The system of claim 6, wherein: In the first sensing mode, the sensor assembly detects the object in the data stream when the size of the object is above a first threshold; as well as In the second sensing mode, the sensor assembly detects the object in the data stream from predetermined image features and it is present in a number of image frames above a threshold.

9. The system of claim 2, comprising a plurality of sensors, including sensors distributed around the top of the elevator car, and wherein: When the sensor captures image data including the object, the sensor component: instructing each of the plurality of sensors to operate in the second sensing mode; or The sensor is merely instructed to operate in the second sensing mode.

10. The system according to claim 1, wherein: Upon entering the second sensing mode, the sensor assembly executes a countdown timer and returns to the first sensing mode upon failure to detect the object in the second sensing mode before the timer expires.

11. A method of controlling an elevator system having an elevator car, a hoistway and a pit, the method comprising: monitoring, in a first sensing mode, using a sensor assembly including a sensor and configured to capture and process images to detect whether an object that may be a human being is located in a first area of ​​the elevator system; After detecting the object in the first area in the first sensing mode, monitoring with the sensor assembly in a second sensing mode that is more sensitive than the first sensing mode to detect the object in the second sensing mode; as well as When the object is detected in the second sensing mode, an elevator safety chain is opened to stop the elevator car.

12. The method according to claim 11, wherein: The sensor assembly is mounted to the elevator car, the elevator car includes a roof, and the first region is the roof of the elevator car.

13. The method according to claim 11, wherein: The sensor is a motion, depth or distance sensor.

14. The method according to claim 11, wherein: The sensor is one of LIDAR, RADAR or a camera.

15. The method according to claim 11, wherein: The sensor is a millimeter wave RADAR or an RGBD camera.

16. The method of claim 11, wherein: In the first sensing mode, the sensor captures images at a first frame rate and at a first spatial resolution; as well as In the second sensing mode, the sensor captures images at a second frame rate higher than the first frame rate and at a second spatial resolution higher than the first spatial resolution.

17. The method according to claim 16, wherein: In the second sensitivity mode, the sensing component focuses on an area or spatial volume that includes the image of the object in the first sensitivity mode.

18. The method of claim 16, wherein: In the first sensing mode, the sensor assembly detects the object in the data stream when the size of the object is above a first threshold; as well as In the second sensing mode, the sensor assembly detects the object in the data stream from predetermined image features and it is present in a number of image frames above a threshold.

19. The method of claim 12, wherein: A plurality of sensors including the sensor are distributed around the top of the elevator car, and wherein, when the sensor captures image data including the object, the sensor assembly: instructing each of the plurality of sensors to operate in the second sensing mode; or The sensor is merely instructed to operate in the second sensing mode.

20. The method according to claim 11, wherein: Upon entering the second sensing mode, the sensor assembly executes a countdown timer and returns to the first sensing mode upon failure to detect the object in the second sensing mode before the timer expires.

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