Virtual safety net for top handrail of lift car

Abstract

An elevator system has a hoistway, a pit, and an elevator car; a sensor assembly, wherein the sensors are distributed around the elevator car and configured to form a virtual safety net (VSN) surrounding at least a portion of a first area outside the elevator car; and an elevator safety chain, wherein the sensor assembly is configured to: monitor destruction of the VSN by an object potentially being a human; and upon detecting destruction of the VSN by the object, opening the elevator safety chain and stopping the elevator car.

Description

Technical Field

[0001] Embodiments herein relate to elevator safety systems, and more particularly to a car top handrail virtual safety net (VSN). Background Art

[0002] Potentially dangerous conditions may exist in the hoistway due to the inability to gain and maintain control of the car or counterweight. Therefore, human sensing devices that initiate the elevator safety chain (e.g., cut drive power and engage the machine brakes) may be installed in the hoistway and on top of the car to make the system foolproof.

[0003] A cost-effective ability to detect mechanical tilt on a car top handrail is desirable. A challenge for such a system is the possible presence of car top components located in the field of view of the utilized sensor. Additionally, the position of the mechanic when working on the handrail may obstruct the sensor's field of view. Summary of the invention

[0004] An elevator system is disclosed, the elevator system comprising: a hoistway, a pit and an elevator car; a sensor assembly, wherein the sensors are distributed around the elevator car and are configured to form a virtual safety net (VSN) surrounding at least a portion of a first area outside the elevator car; and an elevator safety chain, wherein the sensor assembly is configured to: monitor for damage to the VSN by an object that may be a human; and upon detecting damage to the VSN by the object, open the elevator safety chain and stop the elevator car.

[0005] Additionally or alternatively to one or more aspects of the system, the sensor assembly is mounted to the elevator car including a roof, and the first area is the roof of the elevator car.

[0006] In addition to or alternatively to one or more aspects of the system, the system includes: a handrail system located at the top of the elevator car, wherein the VSN extends around the handrail system and vertically extends a predetermined distance above the handrail system to define a set of virtual sensing planes; and adjacent virtual sensing planes in the virtual sensing planes are perpendicular to each other.

[0007] Additionally or alternatively to one or more aspects of the system, the handrail system has four corners; one of the sensors is located at each of the corners of the handrail system; and each of the sensors provides one of the virtual sensing planes.

[0008] Additionally or alternatively to one or more aspects of the system, the sensor is a motion, depth or range sensor.

[0009] Additionally or alternatively in addition to one or more aspects of the system, the sensor includes one of a LIDAR, a RADAR, or a camera.

[0010] Additionally or alternatively in addition to one or more aspects of the system, the sensor comprises millimeter wave RADAR.

[0011] Additionally or alternatively in addition to one or more aspects of the system, the sensor comprises an RGBD camera.

[0012] In addition to or as an alternative to one or more aspects of the system, the VSN defines a safety area surrounded by the VSN; the sensor assembly is configured to monitor when the object is within the safety area, and when the object is detected within the safety area, the sensor assembly opens the elevator safety chain to stop the elevator car.

[0013] Additionally or alternatively to one or more aspects of the system, the sensor assembly is configured to determine that a predetermined minimum number of sensor scans by sensors capture the object violating the VSN or being within the safety zone before the sensor assembly opens the elevator safety chain to stop the elevator car.

[0014] Further disclosed is a method of controlling an elevator system including a hoistway, a pit and an elevator car, the method comprising: forming a virtual safety net (VSN) by a sensor assembly, wherein the sensors are distributed around the elevator car and form the VSN of at least a portion of a first area surrounding an exterior of the elevator car; monitoring, by the sensor assembly, a breach of the VSN by an object that may be a human; and opening the elevator safety chain to stop the elevator car when the sensor assembly detects that the object has breached the VSN.

[0015] Additionally or alternatively to one or more aspects of the method, the sensor assembly is mounted to the elevator car including a roof, and the first area is the roof of the elevator car.

[0016] In addition to or alternatively to one or more aspects of the method, the VSN extends around the top of a handrail system located at the top of the elevator car and extends vertically a predetermined distance above the handrail system to define a set of virtual sensing planes; and the method includes: orienting adjacent ones of the virtual sensing planes to be perpendicular to each other.

[0017] Additionally or alternatively to one or more aspects of the method, the handrail system has four corners; and the method comprises positioning one of the sensors at each of the corners of the handrail system such that each of the sensors provides one of the virtual sensing planes.

[0018] Additionally or alternatively to one or more aspects of the method, the sensor is a motion, depth or range sensor.

[0019] Additionally or alternatively to one or more aspects of the method, the sensor includes one of a LIDAR, a RADAR, or a camera.

[0020] Additionally or alternatively to one or more aspects of the method, the sensor comprises a millimeter wave RADAR.

[0021] Additionally or alternatively to one or more aspects of the method, the sensor comprises an RGBD camera.

[0022] In addition to or as an alternative to one or more aspects of the method, the method includes: defining, by the sensor assembly, a safety area surrounded by the VSN; monitoring, by the sensor assembly, when the object is within the safety area; and opening, by the sensor assembly, the elevator safety chain to stop the elevator car when the object is detected by the sensor assembly to be within the safety area.

[0023] In addition or as an alternative to one or more aspects of the method, the method includes: after determining by the sensor assembly that the sensor captures the object breaching the VSN or within the safety zone with a predetermined minimum number of sensor scans, opening, by the sensor assembly, the elevator safety chain to stop the elevator car. Unless expressly indicated otherwise, the aforementioned features and elements may be combined in various combinations without exclusivity.

[0024] These features and elements and their operation will become more apparent in view of the following description and drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature, rather than restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present disclosure is illustrated by way of example and not limitation by the accompanying figures in which like references indicate similar elements.

[0026] Figure 1 is a schematic illustration of an elevator system in which various embodiments of the present disclosure may be employed;

[0027] Figure 2Additional aspects of an elevator system configured with a plurality of motion sensors for detecting objects on top of an elevator car are shown;

[0028] Figure 3 Further aspects of an elevator system configured with a plurality of motion sensors for detecting objects on top of an elevator car are shown;

[0029] Figure 4 A representative view of the safety net is shown, where the shaded area is the detection zone;

[0030] Figure 5 is a flow chart of a process performed by an elevator system to utilize a virtual safety net to detect an object on top of an elevator car and to responsively control the elevator car; and

[0031] Figure 6 is a flow chart generally illustrating a process performed by an elevator system to utilize a virtual safety net to detect an object on top of an elevator car and responsively control the elevator car. DETAILED DESCRIPTION

[0032] 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, which 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 by 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 movement of the elevator car 103 in an elevator shaft or hoistway 117 and along the guide rail 109 relative to the counterweight 105 simultaneously and in opposite directions.

[0033] 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. A position reference system 113 may be mounted on a fixed portion at the top of the elevator shaft 117, such as on a support or rail, and the position reference system 113 may 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 may be mounted directly to the moving components of the machine 111, or may be located in other locations and / or configurations as known in the art. The position reference system 113 may be any device or mechanism for monitoring the position of the elevator car and / or counterweight as known in the art. For example, without limitation, the position reference system 113 may be an encoder, a sensor, or other system and may include speed sensing, absolute position sensing, etc., as will be appreciated by those skilled in the art.

[0034] 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, and in particular the elevator car 103. It is to be appreciated that the controller 115 need not be located in the controller room 121, but may be located 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 as controlled by 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 in other locations or positions within the elevator system 101. In one embodiment, the system controller 115 may be remotely located or located in a distributed computing network (eg, a cloud computing architecture). The system controller 115 may be implemented using a processor-based machine such as a personal computer, a server, a distributed computing network, or the like.

[0035] 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 source for the motor may be any power source (including an electrical grid) that is supplied to the motor (in combination with other components). The machine 111 may include a traction wheel that transmits force to the tension member 107 to move the elevator car 103 within the elevator shaft 117.

[0036] 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.

[0037] like Figure 2 As shown in FIG. 1 , the elevator car 10 in the hoistway 117 (including the rear wall 117a) has a sensor assembly 150, which may include one or more sensors 140, and may further include a processor 145 or communicate with the processor 145, and the processor 145 may capture and process the image 142. The sensor assembly 150 has a memory and a communication circuit module so that it communicates with the system controller 115 via an intelligent safety control system, for example. The sensor assembly 150 may include a link to a controllable relay that can be turned on to turn on the safety chain. The connection to the safety chain may be made via an electric relay or via a transmitted message sent to the elevator safety system (including the system controller 115) via an intelligent safety control system.

[0038] The car top 130 may be equipped with a handrail system 135 and a sensor 140, the sensor 140 including a first sensor 140a, which is disposed on the handrail system 135. 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 range sensor or a depth sensor, and may be a motion sensor. The sensor 140 may be a LIDAR, a RADAR such as a millimeter wave RADAR, or a camera such as an RGBD camera.

[0039] The sensor assembly 150 is configured to sense when an object 155 of interest, which indicates its size and movement as potentially human, is above the elevator car 103 and extends beyond the elevator car, e.g., into the hoistway 117, and the elevator safety chain is activated. This results in the drive power from the machine 111 being cut off and the machine brake 160 being engaged. The sensor assembly 150 may alternatively be mounted at other locations on the elevator car, such as the bottom, or at other locations on the elevator system, such as within the hoistway, pit (including pit ladders). Figure 3 A configuration of handrail sensors 140 (which are LIDAR sensors) is shown, which are configured to create a virtual safety net (VSN) 200 or virtual safety fence extending above the track 135. Four LIDAR sensors 140a-140d are positioned at respective ones of the four corners 135c1-135c4 of the handrail system 135 on the top 130 of the car 103.

[0040] Each of the sensors 140 creates a two-dimensional (2D) virtual sensing plane 210a-210d over an adjacent length of the handrail system 135, otherwise referred to as a virtual planar fence segment of the VSN 200. That is, a four-sided elevator car 103 having sides 103a-103d has a handrail system 135 (having four handrail sides 135a-135d). Over the handrail system 135, the four sensors 140a-140d create a set of four virtual sensing planes 210a-210d, one along each of the handrail sides 135a-135d. Adjacent ones of the sensing planes 210a-210d are perpendicular to one another. Thus, the sensing planes 210a-210d of the VSN 200 are oriented and aligned such that together they form the VSN 200 over the handrail system 135.

[0041] VSN 200 defines a safety zone 220 that extends around handrail sides 135a-135d and projects a predetermined vertical height VH of about one meter above handrail system 135. This configuration ensures adequate detection of any part of a person reaching therein (such as a mechanic's arm).

[0042] Figure 4 A representative view of VSN 200 is shown. Safety area 220 is located on handrail sides 135a-135d ( Figure 3 ) extends above and between each length. Through VSN 200, sensor assembly 150 ( Figure 3 ) can be detected in the handrail system 135 ( Figure 3 ). In addition, beyond VSN 200, sensor assembly 140 may sense one or more walls of elevator shaft 117, such as rear wall 117A. When sensor assembly 150 determines that a minimum number of sensor scans along VSN 200 ( Figure 3 ) senses an object, such as arm 155A, extending through VSN 200 and into safe area 220, triggering human detection to avoid false alarms. When object 155 is detected above elevator car 103 and through VSN 200, for example, into the hoistway or into safe area 220, the elevator safety chain is opened. This results in cutting off the drive power from machine 111 and engaging machine brake 160.

[0043] The sensor 140 typically scans its corresponding area in its field of view at an update rate (scans / second). Figure 4A "point cloud" of what a single scan would produce as a sensed range value is shown. Detection of humans can be determined by looking at the individual scans as described above and the points that appear therein, but also determining their persistence over the range of the scan in time. Thus, both image processing (as described above) and video processing (video frames with multiple scans) can be used for robust human detection, and are therefore within the scope of the present disclosure.

[0044] Figure 5 is a flow chart of a process performed by the elevator system 101 to utilize the VSN 200 to detect an object 155 on the top 130 of the elevator car 103 and responsively control the elevator car 103, such as to stop.

[0045] As shown in block 510, the method includes forming the VSN 200 by a sensor assembly 150 mounted to the elevator car 103, the sensor assembly including a sensor 140 that captures and processes an image 142 and a processor 145, wherein the sensor 140 is mounted around at least a portion of a first area 127 outside the elevator car 103. As shown in block 520, forming the VSN (block 510) may include positioning one of the sensors 140 at each of the corners 134c1-135c4 of the handrail system 135 on the top 130 of the elevator car 103. As shown in block 530, the method may include orienting adjacent ones of the virtual sensing planes 210a-210d formed by the sensors 140 that together form the VSN 200 so that they are perpendicular to each other. An alternative embodiment would be for the sensor to be located at the center of the track segment and scanned around it using a 180 degree FOV (field of view) to cover the VSN area 135.

[0046] As shown in block 540, the method includes monitoring, by the sensor assembly 150 of the elevator car 103, a breach of the VSN 200 by the object 155. As shown in block 550, the method includes opening the elevator safety chain to control the drive 111 and the machine brake 160 to stop the elevator car 103 when the sensor assembly 150 detects that the object 150 breaches the VSN 200.

[0047] As shown in block 560, the method may include defining, by the sensor assembly 150, a safety zone 220 enclosed by the VSN 200. As shown in block 570, the method may include monitoring, by the sensor assembly 150, when the object 155 is within the safety zone 210. As shown in block 580, upon the sensor assembly 150 detecting that the object 155 is within the safety zone 210, the method may include opening, by the sensor assembly 150, an elevator safety chain to stop the elevator car 103. As shown in block 590, the method may include opening the elevator safety chain to stop the elevator car 103 after a predetermined minimum number of sensor scans within the safety zone 210 after it is determined by the sensor assembly 150 that the object 155 is breaching the VSN 200 or is within the safety zone 210.

[0048] Figure 6 6 is a flow chart generally illustrating a process performed by the elevator system 101 to utilize the VSN 200 to detect an object 155 on the top 130 of the elevator car 103 and responsively control the elevator car 103, e.g., to stop. As shown in block 610, the method includes forming the VSN 200 with a sensor assembly 150 mounted to the elevator car 103, the sensor assembly including a sensor 140 that captures and processes an image 142 and a processor 145, wherein the sensor 140 is mounted around at least a portion of a first area 127 exterior to the elevator car 103. As shown in block 620, the method includes monitoring, by the car sensor assembly 150 of the elevator car 103 operatively coupled to the sensor 140, for damage to the VSN 200 by the object 155. As shown in block 630 , the method includes opening the elevator safety chain to control the drive 111 and the machine brake 160 to stop the elevator car 103 when the sensor assembly 150 detects that the object 155 has breached the VSN 200 .

[0049] The disclosed system is relatively easy to install and adjust, requiring minimal service and maintenance. It is capable of providing high detection performance with low false alarms and negative results. It is a relatively simple, low-cost, effective system for detecting mechanical tilt on the car top handrail, and it is robust and can be applied to a wide range of car top layouts, reducing concerns about vantage points of obstruction or blockage.

[0050] In the disclosed embodiment, sensors 140 are distributed around a first area 127 outside of the elevator car 103, which is the top 130 of the elevator car 103. The disclosed detection systems and processes can be applied to other areas of the elevator system 101, such as pit areas, ladders, etc.

[0051] The sensor data identified herein may be obtained and processed and stitched together individually, or simultaneously, or a combination thereof, and may be processed in raw or compiled form. The sensor data may be processed on the sensor by a controller identified or implied herein, on a cloud service, or by a combination of one or more of these computing systems (e.g., via edge computing). The sensor may transmit data via a wired or wireless transmission line using one or more protocols as indicated below.

[0052] Wireless connection can apply the protocol including local area network (LAN or WLAN representing wireless LAN) protocol. LAN protocol includes WiFi technology based on the subsection 802.11 standard from 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 long-range communication at low bit rates, enabling terminal devices to operate for extended periods of time (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 network servers and application servers, respectively. LAN and WAN protocols can generally be considered to be TCP / IP protocols (Transmission Control Protocol / Internet Protocol) used to manage the connection of computer systems to the Internet. Wireless connection can also apply the protocol including dedicated area network (PAN) protocol. PAN protocol includes, for example, Bluetooth Low Energy (BTLE), which is a wireless technology standard designed and marketed by the Bluetooth Special Interest Group (SIG) for exchanging data over short distances using short wavelength radio waves. PAN protocols also include Zigbee, a technology based on section 802.15.4 from IEEE, representing a suite of advanced communications protocols used to create personal area networks with small low-power digital radio units for low-power, low-bandwidth needs. Such protocols also include Z-Wave, a wireless communication protocol supported by the Z-Wave Alliance that uses a mesh network, applying low-energy radio waves to communicate between devices (such as appliances), allowing wireless control thereof.

[0053] The wireless connection may also include radio frequency identification (RFID) technology for communicating with an integrated chip (IC) such as an RFID smart card. In addition, sub-1 GHz RF devices operate in the ISM (industrial, scientific and medical) spectrum band below sub-1 GHz—usually in the 769-935 MHz, 315 MHz and 468 MHz frequency ranges. This spectrum band below 1 GHz is particularly useful for RF IOT (Internet of Things) applications. The Internet of Things (IoT) describes a network of physical objects—"things"—that are embedded with sensors, software and other technologies for the purpose of connecting and exchanging data with other devices and systems via 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, such as exchanging dates between electronic devices over a short distance. NFC standards are defined by the ISO / IEC (defined below), NFC Alliance and GSMA (Global System for Mobile Communications) groups.The above is not intended to limit the scope of applicable wireless technologies.

[0054] 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), which 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 signal connection between DTE (data terminal equipment) such as a computer terminal and DCE (data circuit-terminating equipment or data communications equipment) such as a modem. 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 component for connecting industrial electronic devices. Wireless connections may also include connections provided by PROFIBUS &

[0055] Connectors (cables / interfaces) under the PROFibus (Process Fieldbus) standard managed by PROFINET International (PI). PROFibus is a standard for fieldbus communication in automation technology, published as part of IEC (International Electrotechnical Commission) 61158. Wired communication can also be done via the Controller Area Network (CAN) bus. CAN is a vehicle bus standard that allows microcontrollers and devices to communicate with each other in an application without the need for a host computer. CAN is a message-based protocol published by the International Organization for Standardization (ISO). The above is not intended to limit the scope of applicable wired technologies.

[0056] When data is transmitted between final processors through a network as identified herein, the data may be transmitted in raw form, or may be processed completely or partially at any of the final processors or intermediate processors, such as in a cloud service (e.g., when at least a portion of the transmission path is wireless) or another processor. Data may be parsed, partially or completely processed or compiled at any of the processors, and then spliced ​​together or retained 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 of a large number 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 unit (GPU) hardware arranged in a homogeneous or heterogeneous manner. 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.

[0057] 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). In other words, the system bus may be able to 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 enable electronic communication. The memory executable program, access data or a lookup table or a combination of each, to facilitate its processing, all of which may be stored in advance or received during the execution of its process by other computing devices, such as via a cloud service or another network connection with other processors identified herein.

[0058] Embodiments can take the form of processor-implemented processes and means for practicing those processes, such as a processor. Embodiments can also take the form of computer code-based modules (e.g., computer program products), such as computer program codes, which contain instructions implemented in tangible media (e.g., non-transitory computer-readable media) such as floppy disks, CD ROMs, hard drives, registers on processors as firmware, or any other non-transitory computer-readable media, wherein when the computer program code is loaded into a computer and executed by it, the computer becomes a means for practicing the embodiments. Embodiments can also take the form of computer program code, such as whether stored in a storage medium, loaded into a computer and / or executed by it, or transmitted through a transmission medium (such as through electrical wiring or cabling, through optical fiber, or via electromagnetic radiation), wherein when the computer program code is loaded into a computer and executed by it, the computer becomes a means for practicing exemplary embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.

[0059] The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The singular forms "a", "an" and "the" used herein are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the term "comprising" when used in this specification specifies the presence of the features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, element components and / or groups thereof.

[0060] Those skilled in the art will appreciate that various example embodiments are shown and described herein, each having certain features in a particular embodiment, but the present disclosure is not limited thereto. Rather, the present disclosure can be modified to incorporate any number of variations, alterations, 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 embodiments described. Thus, the present disclosure is not to be viewed as limited by the foregoing description, but only by the scope of the appended claims.

Claims

1. An elevator system, include: Hoistways, pits and elevator cars; a sensor assembly, wherein the sensors are distributed about the elevator car and are configured to form a virtual safety net (VSN) surrounding at least a portion of a first area outside the elevator car; and Elevator safety chain, Wherein, the sensor assembly is configured as follows: monitoring for disruption of the VSN by an object that may be human; and Upon detection of a breach of the VSN by the object, the elevator safety chain is opened and the elevator car is stopped.

2. The system according to claim 1, in, The sensor assembly is mounted to the elevator car including a roof, and the first area is the roof of the elevator car.

3. The system according to claim 2, include: a handrail system at the top of the elevator car, wherein the VSN extends around the handrail system and vertically extends a predetermined distance above the handrail system to define a set of virtual sensing planes; and Adjacent virtual sensing planes among the virtual sensing planes are perpendicular to each other.

4. The system according to claim 3, in: The handrail system has four corners; one of the sensors is located at each of the corners of the handrail system; and Each of the sensors provides one of the virtual sensing planes.

5. The system according to claim 1, in, The sensor is a motion, depth or range sensor.

6. The system of claim 1, in, The sensor includes one of LIDAR, RADAR or a camera.

7. The system of claim 1, in, The sensor includes millimeter wave RADAR.

8. The system of claim 1, in, The sensor comprises an RGBD camera.

9. The system of claim 1, in: The VSN defines a safe area surrounded by the VSN; The sensor assembly is configured to detect when the object is within the safety zone, and The elevator safety chain is opened by the sensor assembly to stop the elevator car when the object is detected within the safety zone.

10. The system of claim 9, in: The sensor assembly is configured to determine that a predetermined minimum number of sensor scans by sensors capture the object breaching the VSN or being within the safety zone before the sensor assembly opens the elevator safety chain to stop the elevator car.

11. A method of controlling an elevator system comprising a hoistway, a pit and an elevator car, the method include: forming a virtual safety net (VSN) from an assembly of sensors, wherein the sensors are distributed about the elevator car and form the VSN surrounding at least a portion of a first area outside the elevator car; monitoring, by the sensor assembly, a breach of the VSN by an object that may be a human; When the sensor assembly detects that the object has breached the VSN, the elevator safety chain is opened to stop the elevator car.

12. The method according to claim 11, in, The sensor assembly is mounted to the elevator car including a roof, and the first area is the roof of the elevator car.

13. The method according to claim 12, in: the VSN extending around the top of a handrail system at the top of the elevator car and extending vertically a predetermined distance above the handrail system to define a set of virtual sensing planes; as well as The method comprises: Adjacent ones of the virtual sensing planes are oriented to be perpendicular to each other.

14. The method according to claim 13, in: The handrail system has four corners; as well as The method comprises: One of the sensors is positioned at each of the corners of the handrail system such that each of the sensors provides one of the virtual sensing planes.

15. The method according to claim 11, in, The sensor is a motion, depth or range sensor.

16. The method of claim 11, in, The sensor includes one of LIDAR, RADAR or a camera.

17. The method of claim 11, in, The sensor includes millimeter wave RADAR.

18. The method of claim 11, in, The sensor comprises an RGBD camera.

19. The method of claim 14, include: defining, by the sensor assembly, a safety zone enclosed by the VSN; monitoring, by the sensor assembly, when the object is within the safety zone; as well as When the object is detected by the sensor assembly within the safety zone, the elevator safety chain is opened by the sensor assembly to stop the elevator car.

20. The method of claim 19, include: The elevator safety chain is opened by the sensor assembly to stop the elevator car after it is determined by the sensor assembly that the sensor captures the object violating the VSN or being within the safety zone with a predetermined minimum number of sensor scans.

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