Method and device for tracking and identifying object based on light curtain and elevator

Abstract

The invention relates to the field of photoelectric detection, in particular to an object tracking and identifying method and device based on a light curtain and an elevator. Whether a target area is invaded by an object or not is judged based on a first detection signal feature of the light curtain at a designated position in the target area; when the target area is invaded by the object, acquiring second detection signal characteristics of two groups of light curtains with a specified position relationship in the target area, and estimating an obstacle range formed by the object in the target area, so as to adjust the detection state of the light curtain part associated with the obstacle range and update the detection signal of the light curtain; and analyzing the updated detection signal to obtain the appearance characteristics of the object in the target area, and judging whether the object meets the peer limitation condition of the target area so as to adjust the space state change operation of the target area. According to the invention, a plurality of groups of light curtains can be utilized to identify the object in a full range, the object entering the target area range is tracked and positioned in an omnibearing manner, and the accuracy and credibility of light curtain tracking identification are improved.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic detection, and in particular, to a method, device, and elevator for tracking and identifying an object based on a light curtain. Background Art

[0002] The light curtain mainly includes a transmitting end array and a receiving end array that are spaced apart and aligned with each other; wherein, the transmitting end array is formed by arranging a plurality of transmitters capable of emitting infrared light in a regular pattern, the receiving end array is formed by arranging a plurality of receivers capable of receiving infrared light and detecting the light intensity in a regular pattern, and the transmitters and receivers are arranged in one-to-one correspondence. When an object moves through the space between the transmitting end array and the receiving end array, it will block the infrared light emitted by the receiving end array, resulting in some receivers in the receiving end array being unable to receive infrared light or the intensity of the received infrared light being reduced. By analyzing the infrared light reception situation of the receiving end array, the position and / or shape and size of the object can be detected.

[0003] As a non-contact optoelectronic detection device, the light curtain can be applied to scenarios such as object position detection and object outline size measurement. Specifically, the light curtain is widely used in elevators to detect whether there is an object in the area where the elevator car door is located, so as to control the automatic opening and closing of the elevator car door and avoid accidents such as incorrect closing of the elevator car door and pinching of people. However, existing elevators usually install a group of light curtains, that is, the transmitting end array and the receiving end array are respectively installed at the top and bottom of the area where the elevator car door is located, which greatly limits the detection range of the light curtain and cannot comprehensively and accurately detect the objects in the area where the elevator car door is located, increasing the probability of false detection. It can be seen that how to use multiple groups of light curtains to identify objects in the full range and achieve the tracking and positioning of objects entering the target area range is of great significance for reducing the probability of false detection of the light curtain and improving the reliability of object tracking and identification. Summary of the Invention

[0004] In order to avoid a high probability of false detection when using a single light curtain to track and identify an object, achieve the omnidirectional tracking and positioning of objects entering the target area range, and improve the reliability of object tracking and identification in the target area range, the present invention provides a method for tracking and identifying an object based on a light curtain, and the method includes the following steps: Obtain the detection signal of the light curtain in the target area, analyze the detection signal to obtain the first detection signal feature; based on the first detection signal feature corresponding to the light curtain at a specified position in the target area, determine whether the target area is invaded by an object; When the target area is invaded by an object, detect signals of two sets of light curtains with a specified positional relationship within the target area; analyze the detection signals of the two sets of light curtains to obtain second detection signal features; based on the second detection signal features, estimate the obstacle range formed by the object within the target area, and accordingly adjust the detection status of the light curtain parts associated with the obstacle range, so as to update the detection signals of all light curtains. Analyze the updated detection signals to obtain the shape features of the object within the target area; based on the shape features, determine whether the object meets the passage restriction conditions of the target area, and accordingly adjust the operation of changing the spatial state of the target area.

[0005] Preferably, for obtaining the detection signals of the light curtains within the target area, analyzing the detection signals to obtain first detection signal features, and based on the first detection signal features corresponding to the light curtains at specified positions within the target area, determining whether the target area is invaded by an object, specifically: Collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and determine whether the intensity of the detection signals changes within a preset time interval; if so, control to obtain the detection signals generated by all the light curtains within the target area; if not, do not control to obtain the detection signals generated by all the light curtains within the target area. Conduct time-domain change analysis on the detection signals generated by all the light curtains respectively to obtain the first detection signal features of all the light curtains respectively; wherein, the first detection signal feature refers to the intensity change feature of the detection signals generated by the light curtain in the time dimension. Based on the first detection signal features corresponding to the light curtains at the opposite edges of the target area, determine the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges; compare the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges to determine whether the target area is invaded by an object.

[0006] Preferably, for when the target area is invaded by an object, obtaining the detection signals of two sets of light curtains with a specified positional relationship within the target area, analyzing the detection signals of the two sets of light curtains to obtain second detection signal features, and based on the second detection signal features, estimating the obstacle range formed by the object within the target area, and accordingly adjusting the detection status of the light curtain parts associated with the obstacle range, so as to update the detection signals of all light curtains, specifically: When the target area is invaded by an object, obtain the detection signals generated by two groups of light curtains perpendicular to each other within the target area; perform spatial variation analysis on the detection signals generated by the two groups of light curtains respectively to obtain the second detection signal feature; wherein, the second detection signal feature refers to the intensity distribution feature of the detection signal generated by the light curtain in the spatial dimension. Based on the second detection signal feature, determine the detection ranges within the two groups of light curtains where effective detection signals cannot be formed respectively; based on the detection ranges, estimate the obstacle range formed by the object within the target area, and thereby adjust the light emission divergence angle of some emission ends inside the light curtain associated with the obstacle range, so as to update the detection signals of all light curtains.

[0007] Preferably, analyze the updated detection signals to obtain the external shape feature of the object within the target area; based on the external shape feature, determine whether the object meets the passage restriction conditions of the target area, and thereby adjust the spatial state change operation for the target area, specifically: Analyze the updated detection signals to obtain the position information of the effective detection light distribution within the entire target area; based on the position information of the effective detection light distribution, determine the external shape feature of the part of the object that has invaded the target area. Based on the external shape feature, determine the cross-sectional size of the object part; compare the cross-sectional size with the upper limit of the allowable passage object size of the passage restriction conditions of the target area to determine whether the object meets the passage restriction conditions, and thereby determine whether to perform a spatial closing operation on the target area.

[0008] On the other hand, the present invention provides an object tracking and recognition device based on a light curtain, and the device includes the following modules: The first detection signal analysis module is used to obtain the detection signals of the light curtain within the target area, and analyze the detection signals to obtain the first detection signal feature. The object intrusion judgment module is used to judge whether the target area is invaded by an object based on the first detection signal feature corresponding to the light curtain at a specified position within the target area. The second detection signal analysis module is used to, when the target area is invaded by an object, obtain the detection signals of two groups of light curtains with a specified positional relationship within the target area; analyze the detection signals of the two groups of light curtains to obtain the second detection signal feature. The detection signal update module is used to estimate the obstacle range formed by the object within the target area based on the second detection signal feature, and thereby adjust the detection state of the light curtain part associated with the obstacle range, so as to update the detection signals of all light curtains. An object shape feature determination module, configured to analyze the updated detection signal to obtain the shape feature of the object in the target area; A target area space change operation module, configured to determine whether the object meets the passage restriction conditions of the target area based on the shape feature, so as to adjust the space state change operation of the target area.

[0009] Preferably, it further includes: A detection signal acquisition control module, configured to collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and determine whether the intensity of the detection signals changes within a preset time interval; if so, control to obtain the detection signals generated by all the light curtains in the target area; if not, do not control to obtain the detection signals generated by all the light curtains in the target area.

[0010] Preferably, the first detection signal analysis module is configured to obtain the detection signals of the light curtains in the target area, analyze the detection signals, and obtain the first detection signal features, specifically: Perform time-domain change analysis on the detection signals generated by all the light curtains respectively to obtain the first detection signal features of all the light curtains respectively; wherein, the first detection signal feature refers to the intensity change feature of the detection signal generated by the light curtain in the time dimension; The object intrusion determination module is configured to determine whether the target area is intruded by an object based on the first detection signal features corresponding to the light curtains at the specified positions in the target area, specifically: Based on the first detection signal features corresponding to the light curtains at the opposite edges of the target area, determine the occurrence time information of the detection signal intensity change alongs corresponding to the light curtains at the opposite edges; compare the occurrence time information of the detection signal intensity change alongs corresponding to the light curtains at the opposite edges to determine whether the target area is intruded by an object.

[0011] Preferably, when the target area is intruded by an object, the second detection signal analysis module is configured to obtain the detection signals of two groups of light curtains with a specified positional relationship in the target area; analyze the detection signals of the two groups of light curtains to obtain the second detection signal features, specifically: When the target area is intruded by an object, obtain the detection signals generated by two groups of mutually perpendicular light curtains in the target area respectively; perform spatial domain change analysis on the detection signals generated by the two groups of light curtains respectively to obtain the second detection signal features; wherein, the second detection signal feature refers to the intensity distribution feature of the detection signal generated by the light curtain in the spatial dimension; The detection signal update module is used to estimate the obstacle range formed by the object in the target area based on the second detection signal feature, and thereby adjust the detection status of the light curtain part associated with the obstacle range, so as to update the detection signals of all light curtains. Specifically: Based on the second detection signal feature, determine the detection ranges within the two groups of light curtains where effective detection signals cannot be formed respectively; based on the detection ranges, estimate the obstacle range formed by the object in the target area, and thereby adjust the light emission divergence angles of the internal emission ends of the light curtains associated with the obstacle range, so as to update the detection signals of all light curtains.

[0012] Preferably, the object shape feature determination module is used to analyze the updated detection signals to obtain the shape features of the object in the target area. Specifically: Analyze the updated detection signals to obtain the position information of the effective detection light distribution within the global range of the target area; based on the position information of the effective detection light distribution, determine the shape features of the part of the object that has invaded the target area. The target area space change operation module is used to determine whether the object meets the passage restriction conditions of the target area based on the shape features, and thereby adjust the space state change operation of the target area. Specifically: Based on the shape features, determine the cross-sectional size of the object part; compare the cross-sectional size with the upper limit of the allowable passage object size of the passage restriction conditions of the target area, and determine whether the object meets the passage restriction conditions, so as to determine whether to perform a space closing operation on the target area.

[0013] In addition, the present invention also provides an elevator, which includes: The above-mentioned device for tracking and identifying an object based on a light curtain.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Obtain the detection signal of the light curtain within the target area, analyze the detection signal to obtain the first detection signal feature; based on the first detection signal feature corresponding to the light curtain at a specified position within the target area, determine whether the target area has been invaded by an object. The purpose of setting the light curtain within the target area is to automatically sense and detect whether there is an object within the target area and the location of the object. Among them, the target area can be, but is not limited to, the area where the elevator car door is located. The elevator car door needs to be frequently opened and closed during operation. In order to prevent the elevator car door from pinching people or objects during the closing process, it is necessary to set a light curtain in the space area where the elevator car door opens and closes to detect in real time whether there is an object within this space area. Different from the prior art which only installs light curtains at the top and bottom of this space area (such as installing the emitter array of the light curtain at the top and the receiver array of the light curtain at the top), in this case, light curtains are installed on the opposite two side edges (such as the long side edges of the opposite sides) at the top and bottom of this space area and on the two opposite inner side surfaces of this space area, that is, at least three groups of light curtains are installed within this space area. By installing light curtains in two different dimensions, the vertical direction and the horizontal direction, within this space area, multi-dimensional positioning detection of objects is achieved. When an object invades from outside the target area into the target area, the infrared light emitted by at least some of the emitters within any group of light curtains in the target area will be blocked. The receivers corresponding to these emitters will not be able to receive the infrared light or the intensity of the received infrared light will decrease, resulting in a significant decrease in the intensity of the detection signal generated by the corresponding group of light curtains within a short time interval. According to the above process, by obtaining and analyzing the change characteristics of the detection signal intensity of a certain group of light curtains generated within the target area in the time domain, it is possible to quickly and accurately determine whether the target area has been invaded by an object. Compared with the original situation where only one group of light curtains was installed within the target area, the detection space range formed by a single group of light curtains within the target area is limited. If the object invading into the target area is a small-volume or thin and flat-shaped object, the detection space range formed by the light curtain may not cover the object, resulting in a misjudgment that the object has not invaded into the target area. In this case, light curtains are installed in at least two different dimensional directions within the target area, which can increase the detection space range of the light curtain within the target area and effectively reduce the probability of a small-volume or thin and flat-shaped object entering the target area and not being detected in a timely and accurate manner.

[0015] When the target area is invaded by an object, detect the signals of two sets of light curtains with a specified positional relationship within the target area; analyze the detection signals of the two sets of light curtains to obtain the characteristics of the second detection signal; based on the characteristics of the second detection signal, estimate the obstacle range formed by the object within the target area, and accordingly adjust the detection state of the light curtain part associated with the obstacle range, so as to update the detection signals of all light curtains. When the target area is invaded by an object, all or part of the object will be within the target area, thus forming an obstacle range within the target area. Generally speaking, the larger the volume of the part of the object invading the target area, the larger the obstacle range formed within the target area; considering that there is an interval between any two adjacent transmitters within the same set of light curtains, the infrared light emitted by all transmitters within the same set of light curtains cannot effectively overlap to form a continuous infrared detection space, resulting in problems such as false detection or missed detection of the light curtain. In particular, the larger the obstacle range formed by the object within the target area, the larger the outer contour surface of the part of the object invading the target area, and the greater the probability of false detection or missed detection of the corresponding outer contour surface by the light curtain. In order to reduce the probability of false detection or missed detection of objects within the target area when only one set of light curtains is used to detect in a single dimension direction, synchronously detect the objects within the target area by two sets of light curtains perpendicular to each other within the target area in two different dimension directions, and determine the infrared light shielding situation of the object to the two sets of light curtains in the two different dimension directions. The part of the object located within the target area forms shielding to the light curtains in the corresponding dimensions in the two different dimension directions respectively. For example, it shields the infrared light emitted by the corresponding light curtains in the vertical and horizontal directions. Correspondingly, the intensity distribution of the detection signals generated by the two light curtains in the two different dimension directions within the target area will also be different. The intensity of the detection signals generated in the area range shielded by the object part significantly decreases or directly becomes zero, while the intensity of the detection signals generated in the area range not shielded by the object part remains the original intensity value. The difference in the intensity distribution of the detection signals generated by the above two sets of light curtains in the spatial dimension directly characterizes the spatial domain change situation of the detection signals. Then, based on the difference characteristics of the intensity distribution of the detection signals generated by the two sets of light curtains in the spatial dimension, determine the detection ranges within the two sets of light curtains where effective detection signals cannot be formed respectively, that is, the detection ranges where the intensity of the detection signals formed within the light curtains is less than the preset intensity threshold, and based on the above detection ranges, estimate the obstacle range formed by the object within the target area, so as to define the occupied space range of the object within the target area. Then, based on the obstacle range formed by the object within the target area, adjust the divergence angle of the infrared light irradiation of some transmitters within the light curtain associated with the obstacle range, improve the accuracy of the infrared light irradiation of the corresponding part of the object by the light curtain, and reduce the probability of false detection and missed detection.

[0016] Analyze the updated detection signal to obtain the external shape characteristics of the object in the target area; based on the external shape characteristics, determine whether the object meets the passage restriction conditions of the target area, so as to adjust the operation of changing the spatial state of the target area. When the detection state of the light curtain associated with the obstacle range formed by the object in the target area is adjusted, the detection signal generated by the corresponding light curtain will also be updated and changed accordingly, and the updated detection signal more accurately reflects the occupied space size of the object in the target area. In order to more accurately identify the spatial dimensions of an object invading the target area, analyze the updated detection signal to obtain the distribution position information of the effective detection light rays within the global range of the target area, that is, the distribution position information of the infrared light rays that are not blocked by the object and have an intensity exceeding the preset intensity threshold within all the light curtains in the global range of the target area; then, based on the distribution position information of the effective detection light rays, use the distribution positions of the infrared light rays that are not blocked by the object and have an intensity exceeding the preset intensity threshold within all the light curtains as the boundaries to determine the external shape characteristics of the part of the object invading the target area, and further determine the cross-sectional size of the part of the object invading the target area. Then, compare the above cross-sectional size with the upper limit of the allowable passage object size of the passage restriction conditions of the target area to determine whether the object meets the passage restriction conditions, so as to determine whether to implement a spatial closing operation on the target area, ensuring that the target area will not be closed when invaded and occupied by the object, effectively avoiding accidents. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. Among them: Figure 1 is a flowchart of a method for tracking and identifying an object based on a light curtain provided by the present invention.

[0018] Figure 2 is a schematic diagram of the light curtain layout of the target area in a method for tracking and identifying an object based on a light curtain provided by the present invention.

[0019] Figure 3 is a structural diagram of a device for tracking and identifying an object based on a light curtain provided by the present invention. Detailed Embodiments

[0020] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following will describe in detail the specific embodiments of the present invention with reference to the accompanying drawings. It can be understood that the specific embodiments described herein are only for explaining the present invention and not for limiting the present invention. Additionally, it should be noted that for the sake of convenience of description, only the parts related to the present invention rather than all the structures are shown in the drawings. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0021] The terms "comprising" and "having" in the present invention and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products, or devices.

[0022] Referring to the embodiments herein means that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present invention. The phrase appears at various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0023] Please refer to Figure 1 As shown, the present invention provides a method for tracking and identifying an object based on a light curtain, and the method includes the following steps: S100, obtain the detection signal of the light curtain in the target area, analyze the detection signal to obtain the first detection signal feature; based on the first detection signal feature corresponding to the light curtain at a specified position in the target area, determine whether the target area is invaded by an object. [[ID=1�]]

[0024] Further, obtaining the detection signal of the light curtain in the target area, analyzing the detection signal to obtain the first detection signal feature; based on the first detection signal feature corresponding to the light curtain at a specified position in the target area, determining whether the target area is invaded by an object, specifically: Collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and determine whether the intensity of the detection signals changes within a preset time interval; if so, control to obtain the detection signals generated by all the light curtains in the target area respectively; if not, do not control to obtain the detection signals generated by all the light curtains in the target area respectively; Perform time-domain variation analysis on the detection signals generated by all the light curtains respectively to obtain the first detection signal features of all the light curtains respectively; wherein, the first detection signal feature refers to the intensity variation feature of the detection signal generated by the light curtain in the time dimension; Based on the first detection signal features corresponding to the light curtains located at the opposite two side edges of the target area, determine the occurrence time information of the change along the detection signal intensity corresponding to the light curtains at the opposite two side edges; compare the occurrence time information of the change along the detection signal intensity corresponding to the light curtains at the opposite two side edges to determine whether the target area is invaded by an object.

[0025] The purpose of setting the light curtains in the target area is to automatically sense and detect whether there is an object in the target area and the location where the object exists. Among them, the target area can be but is not limited to the area where the elevator car door is located. During the operation of the elevator car door, it needs to be frequently opened and closed. In order to prevent the elevator car door from pinching people or objects during the closing process, it is necessary to set light curtains in the space area where the elevator car door opens and closes, and detect in real time whether there is an object in this space area. Different from the prior art where light curtains are only installed at the top and bottom of this space area (such as installing the transmitting end array of the light curtain at the top and the receiving end array of the light curtain at the top), in this case, light curtains are installed on the opposite two side edges (such as the long side edges on the opposite two sides) at the top and bottom of this space area and on the opposite two inner side surfaces of this space area, that is, at least three groups of light curtains are installed in this space area. By installing light curtains in two different dimensions, namely the vertical direction and the horizontal direction, in this space area, multi-dimensional positioning detection of objects is realized. The layout of the light curtains in the target area is as Figure 2 shown. Transmitting end arrays are arranged on the two long side edges at the top of the target area, and receiving end arrays are arranged on the two long side edges at the bottom of the target area. In this way, the transmitting end arrays and receiving end arrays at the top and bottom of the target area correspond to each other and jointly form two groups of light curtains, which can perform light curtain detection on the target area in two different planes. In addition, a transmitting end array is installed on the inner side surface on the left of the target area, and a receiving end array is installed on the inner side surface on the right of the target area. In this way, the transmitting end arrays and receiving end arrays on the inner side surfaces on the left and right of the target area jointly form a group of light curtains. Installing three groups of light curtains in the target area can improve the light curtain detection sensitivity of the interior of the target area and avoid false detection or missed detection due to the object invading the target area being too small in volume or having a flat shape.

[0026] Under normal circumstances, it is only necessary to collect and analyze the detection signals generated by the light curtain to determine whether the target area has been invaded by an object. In an actual scenario, the target area corresponds to the opening and closing activity area of the elevator car door. When the elevator car door is in a fully closed state, no object will invade the target area. If the detection signals generated by the light curtain are still collected and analyzed, it will increase the workload of processing the detection signals. To avoid continuously collecting and analyzing the detection signals generated by the light curtain when the target area is in a fully closed state, the detection signals generated by the light curtain part located at the corner of the target area can be collected first. For example, the detection signals generated by the light curtain parts corresponding to the transmitting and receiving ends at the four corners at the top and bottom of the target area can be collected first. Among them, the transmitting end can be, but is not limited to, an infrared light emitter, and the receiving end can be, but is not limited to, an infrared light intensity sensor. When the target area switches from a fully closed state to a fully open state, the intensity of the detection signals corresponding to the transmitting and receiving ends at the four corners will increase from zero to a stable intensity value in a short period of time. Therefore, by analyzing the detection signals generated by the light curtain part located at the corner of the target area, it is judged whether the intensity of the detection signals changes within a preset time interval, so as to determine whether the target area is in a fully open state. Only when the intensity of the detection signals generated by the light curtain part located at the corner of the target area changes within the preset time interval can it be determined that the target area is in a fully open state. At this time, the detection signals generated by all the light curtains in the target area are controlled to be obtained, so as to avoid increasing the workload of processing the detection signals by continuously collecting and analyzing the detection signals generated by the light curtain during the process of the target area being in a fully closed state.

[0027] According to the foregoing analysis, when only one set of light curtains is installed in the target area, for example, only one set of light curtains is installed between the top and bottom of the target area, when an object with a too small volume or a flat shape invades the target area, the light curtain cannot detect the presence of the object. To avoid the above situation, two sets of light curtains are arranged in a non-coplanar manner between the top and bottom of the target area. When an object enters the target area from outside the target area, every time it moves past the light curtain, the intensity of the detection signal generated by the light curtain will change. Given that the two sets of light curtains are located in different planes inside the target area, when the object moves from outside the target area to inside the target area and then from inside the target area to outside the target area, the occurrence times of the intensity changes of the detection signals generated by the two sets of light curtains are not the same. During the above process, there will be a sequential intensity change in the inspection signal intensities generated by the two sets of light curtains; when the object moves from outside the target area to inside the target area but does not move from inside the target area to outside the target area, only the intensity of the detection signal generated by one set of light curtains will change, and the intensity of the detection signal generated by the other set of light curtains will not change. Based on the above analysis, by determining the relative relationship of the occurrence times of the intensity changes of the detection signals generated by the two sets of light curtains respectively, it can be judged whether the target area is invaded by an object. Specifically, first, perform time-domain change analysis on the detection signals generated by all the light curtains in the target area respectively to obtain the intensity change characteristics of the detection signals generated by each light curtain in the time dimension, that is, the occurrence times of the intensity change rising edge and / or intensity change falling edge of the detection signal intensity curve generated by each light curtain; then, based on the detection signal intensity change characteristics of the two sets of light curtains located at the long side edges on both the top and bottom sides of the target area, obtain the occurrence times of the intensity change rising edge and / or intensity change falling edge of the detection signal intensity curves generated by the two sets of light curtains, and compare the occurrence times of the intensity change rising edge and / or intensity change falling edge corresponding to the two sets of light curtains, so as to judge whether the target area is invaded by an object, effectively reducing the occurrence probability that small-volume or thin flat-shaped objects enter the target area and cannot be detected in a timely and accurate manner.

[0028] S200, when the target area is invaded by an object, obtain the detection signals of two sets of light curtains with a specified positional relationship in the target area; analyze the detection signals of the two sets of light curtains to obtain the second detection signal characteristics; based on the second detection signal characteristics, estimate the obstacle range formed by the object in the target area, and adjust the detection state of the light curtain part associated with the obstacle range accordingly, so as to update the detection signals of all the light curtains.

[0029] Furthermore, when the target area is invaded by an object, detection signals of two sets of light curtains with a specified positional relationship within the target area are acquired; the detection signals of the two sets of light curtains are analyzed to obtain second detection signal features; based on the second detection signal features, the obstacle range formed by the object within the target area is estimated, and accordingly, the detection states of the light curtain parts associated with the obstacle range are adjusted, thereby updating the detection signals of all the light curtains, specifically as follows: When the target area is invaded by an object, detection signals respectively generated by two sets of mutually perpendicular light curtains within the target area are acquired; spatial variation analysis is performed on the detection signals respectively generated by the two sets of light curtains to obtain second detection signal features; wherein, the second detection signal features refer to the intensity distribution features of the detection signals generated by the light curtains in the spatial dimension; Based on the second detection signal features, the detection ranges within the two sets of light curtains where effective detection signals cannot be formed respectively are determined; based on the detection ranges, the obstacle range formed by the object within the target area is estimated, and accordingly, the light emission divergence angles of the internal partial transmitters within the light curtains associated with the obstacle range are adjusted, thereby updating the detection signals of all the light curtains.

[0030] When the target area is invaded by an object, all or part of the object will be within the target area, thus forming an obstacle range within the target area. Generally speaking, the larger the volume of the part of the object invading the target area, the larger the obstacle range formed within the target area; considering that there is an interval between any two adjacent transmitters within the same set of light curtains, the infrared light emitted by all the transmitters within the same set of light curtains cannot effectively overlap to form a continuous infrared detection space, resulting in problems such as false detection or missed detection of the light curtain. In particular, the larger the obstacle range formed by the object within the target area, the larger the outer contour surface of the part of the object invading the target area, and the greater the probability of false detection or missed detection of the corresponding outer contour surface by the light curtain.

[0031] In order to reduce the probability of false detection or missed detection of objects in the target area by using only one set of light curtains to detect objects in the target area in a single dimension direction, two sets of light curtains perpendicular to each other in the target area are obtained to synchronously detect objects in the target area in two different dimension directions, and the infrared light occlusion of the two sets of light curtains by the objects in the target area is determined in the two different dimension directions. The object part located in the target area forms occlusions for the light curtains in the corresponding dimensions in the two different dimension directions respectively. For example, the infrared light emitted by the corresponding light curtains is occluded in the vertical and horizontal directions. Correspondingly, the intensity distribution of the detection signals generated by the two sets of light curtains in the two different dimension directions in the target area will also be different. The intensity of the detection signals generated in the area range occluded by the object part significantly decreases or directly becomes zero, while the intensity of the detection signals generated in the area range not occluded by the object part remains the original intensity value. The difference in the intensity distribution of the detection signals generated by the above two sets of light curtains in the spatial dimension directly represents the spatial variation of the detection signals. Then, based on the difference characteristics of the intensity distribution of the detection signals generated by the two sets of light curtains in the spatial dimension, the detection ranges where effective detection signals cannot be formed inside the two sets of light curtains are determined, that is, the detection ranges where the intensity of the detection signals formed inside the light curtains is less than the preset intensity threshold, and based on the above detection ranges, the obstacle range formed by the object in the target area is estimated, so as to define the occupied space range of the object in the target area. The obstacle range formed by the object in the target area is projected onto the top and inner side surfaces of the target area, and the partial transmitters covered by all the transmitters installed on the top and inner side surfaces of the target area within the above obstacle range are determined, and these are used as the partial transmitters inside the light curtain associated with the obstacle range; then, the divergence angle of the infrared light irradiation of the partial transmitters inside the light curtain associated with the obstacle range is adjusted. For example, the emission angle of the infrared light irradiation of the partial transmitters inside the light curtain is reduced to improve the accuracy of the infrared light irradiation of the corresponding part of the light curtain on the object and reduce the probability of false detection and missed detection.

[0032] S300. Analyze the updated detection signals to obtain the shape characteristics of the object in the target area; based on the shape characteristics, determine whether the object meets the passage restriction conditions of the target area, so as to adjust the operation of changing the spatial state of the target area.

[0033] Furthermore, analyze the updated detection signals to obtain the shape characteristics of the object in the target area; based on the shape characteristics, determine whether the object meets the passage restriction conditions of the target area, so as to adjust the operation of changing the spatial state of the target area. Specifically: Analyze the updated detection signals to obtain the position information of the effective detection light distribution in the global range of the target area; based on the position information of the effective detection light distribution, determine the shape characteristics of the object part that has invaded the target area. Based on the external shape characteristics, determine the cross-sectional size of the object part; compare the cross-sectional size with the upper limit of the allowable passing object size of the passing restriction conditions of the target area, and judge whether the object meets the passing restriction conditions, so as to determine whether to perform a space closing operation on the target area.

[0034] When the light curtain adjustment detection state associated with the obstacle range formed by the object in the target area changes, the detection signal generated by the corresponding light curtain will also be updated and changed accordingly, and the updated detection signal more accurately reflects the occupied space size of the object in the target area. In order to more accurately identify the spatial size of the object invading the target area, analyze the updated detection signal to obtain the distribution position information of the effective detection light in the global range of the target area, that is, the distribution position information of the infrared light that is not blocked by the object and has an intensity exceeding the preset intensity threshold in all light curtains within the global range of the target area; then based on the distribution position information of the effective detection light, take the distribution position of the infrared light that is not blocked by the object and has an intensity exceeding the preset intensity threshold in all light curtains as the boundary to determine the external shape characteristics of the object part invading the target area, and then determine the cross-sectional size of the object part invading the target area, and then compare the above cross-sectional size with the upper limit of the allowable passing object size of the passing restriction conditions of the target area to judge whether the object meets the passing restriction conditions. For example, determine the maximum length dimension of the cross-section from the above cross-sectional size, and compare the above maximum length dimension with the upper limit of the allowable passing object size of the passing restriction conditions of the target area. If the above maximum length dimension exceeds the above allowable passing object size upper limit, it is judged that the object does not meet the passing restriction conditions; otherwise, it is judged that the object meets the passing restriction conditions. When the object does not meet the passing restriction conditions, it is determined not to perform a space closing operation on the target area, that is, not to control the elevator car door to switch to the closed state; when the object meets the passing restriction conditions, it is determined to perform a space closing operation on the target area, that is, to control the elevator car door to switch to the closed state.

[0035] Please refer to Figure 3 As shown, the present invention provides a device for tracking and identifying an object based on a light curtain, and the device includes the following modules: A first detection signal analysis module, configured to obtain the detection signal of the light curtain in the target area, analyze the detection signal, and obtain the first detection signal feature; An object intrusion judgment module, configured to judge whether the target area is invaded by an object based on the first detection signal feature corresponding to the light curtain at a specified position in the target area; A second detection signal analysis module, configured to obtain the detection signals of two groups of light curtains with a specified positional relationship in the target area when the target area is invaded by an object; analyze the detection signals of the two groups of light curtains to obtain the second detection signal feature; The detection signal update module is used to estimate the obstacle range formed by an object in the target area based on the second detection signal feature, thereby adjusting the detection state of the light curtain part associated with the obstacle range, and thus updating the detection signals of all light curtains; The object shape feature determination module is used to analyze the updated detection signals to obtain the shape features of the object in the target area; The target area space change operation module is used to determine whether the object meets the passage restriction conditions of the target area based on the shape features, thereby adjusting the space state change operation of the target area.

[0036] Furthermore, the device further includes: a detection signal acquisition control module, which is used to collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and judge whether the detection signals change in intensity within a preset time interval; if so, control to obtain the detection signals generated by all the light curtains in the target area respectively; if not, do not control to obtain the detection signals generated by all the light curtains in the target area respectively.

[0037] Furthermore, the first detection signal analysis module is used to obtain the detection signals of the light curtains in the target area, analyze the detection signals, and obtain the first detection signal feature, specifically: Perform time-domain change analysis on the detection signals generated by all the light curtains respectively to obtain the first detection signal features of all the light curtains respectively; wherein, the first detection signal feature refers to the intensity change feature of the detection signal generated by the light curtain in the time dimension; The object intrusion judgment module is used to judge whether the target area is invaded by an object based on the first detection signal feature corresponding to the light curtain at a specified position in the target area, specifically: Based on the first detection signal features corresponding to the light curtains at the opposite edges of the target area, determine the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges; compare the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges to judge whether the target area is invaded by an object.

[0038] Furthermore, the second detection signal analysis module is used to obtain the detection signals of two groups of light curtains with a specified positional relationship in the target area when the target area is invaded by an object; analyze the detection signals of the two groups of light curtains to obtain the second detection signal feature, specifically: When the target area is invaded by an object, obtain the detection signals generated by two groups of mutually perpendicular light curtains in the target area respectively; perform spatial domain change analysis on the detection signals generated by the two groups of light curtains respectively to obtain the second detection signal feature; wherein, the second detection signal feature refers to the intensity distribution feature of the detection signal generated by the light curtain in the spatial dimension; The detection signal update module is used to estimate the obstacle range formed by an object in the target area based on the second detection signal feature, and adjust the detection status of the light curtain part associated with the obstacle range, so as to update the detection signals of all light curtains. Specifically: Based on the second detection signal feature, determine the detection ranges within the two groups of light curtains where effective detection signals cannot be formed respectively; based on the detection ranges, estimate the obstacle range formed by the object in the target area, and adjust the light irradiation divergence angle of the internal transmitting ends within the light curtain associated with the obstacle range, so as to update the detection signals of all light curtains.

[0039] Further, the object shape feature determination module is used to analyze the updated detection signals to obtain the shape features of the object in the target area. Specifically: Analyze the updated detection signals to obtain the position information of the distribution of effective detection light rays within the global range of the target area; based on the position information of the distribution of effective detection light rays, determine the shape features of the part of the object that has invaded the target area. The target area space change operation module is used to judge whether the object meets the passage restriction conditions of the target area based on the shape features, so as to adjust the space state change operation of the target area. Specifically: Based on the shape features, determine the section size of the object part; compare the section size with the upper limit of the allowable passage object size of the passage restriction conditions of the target area, judge whether the object meets the passage restriction conditions, and thus determine whether to perform a space closing operation on the target area.

[0040] The light curtain-based object tracking and recognition device of the present invention corresponds to the operation and effect of the above-mentioned light curtain-based object tracking and recognition method, and will not be repeated here for this light curtain-based object tracking and recognition device.

[0041] Please refer to Figure 3 As shown, the present invention provides an elevator, which includes: the above-mentioned light curtain-based object tracking and recognition device.

[0042] Installing the above-mentioned light curtain-based object tracking and recognition device in the elevator can track and recognize the personnel or objects entering and leaving the elevator, and judge whether the personnel or objects stay in the closing activity area of the elevator car door, thereby improving the safety of the elevator operation.

[0043] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of adding a necessary general hardware platform. Of course, it can also be implemented by a combination of hardware and software. Based on such an understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a computer product. The present invention can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Other embodiments can also be adopted. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for tracking and identifying an object based on a light curtain, characterized in that, The method includes the following steps: Obtain the detection signals of the light curtain within the target area, analyze the detection signals to obtain the first detection signal characteristics; based on the first detection signal characteristics corresponding to the light curtain at a specified position within the target area, determine whether the target area has been invaded by an object; When the target area has been invaded by an object, obtain the detection signals of two groups of light curtains having a specified positional relationship within the target area; analyze the detection signals of the two groups of light curtains to obtain the second detection signal characteristics; based on the second detection signal characteristics, estimate the obstacle range formed by the object within the target area, and thereby adjust the detection states of the light curtain parts associated with the obstacle range, so as to update the detection signals of all the light curtains; Analyze the updated detection signals to obtain the shape characteristics of the object within the target area; based on the shape characteristics, determine whether the object meets the passage restriction conditions of the target area, and thereby adjust the spatial state change operation of the target area.

2. The method according to claim 1, wherein the obtaining the detection signals of the light curtain within the target area, analyzing the detection signals to obtain the first detection signal characteristics; based on the first detection signal characteristics corresponding to the light curtain at a specified position within the target area, determining whether the target area has been invaded by an object is specifically: Collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and determine whether the intensity of the detection signals changes within a preset time interval; if so, control to obtain the detection signals respectively generated by all the light curtains within the target area; if not, do not control to obtain the detection signals respectively generated by all the light curtains within the target area; Perform time-domain change analysis on the detection signals respectively generated by all the light curtains to obtain the first detection signal characteristics of all the light curtains respectively; wherein, the first detection signal characteristics refer to the intensity change characteristics of the detection signals generated by the light curtain in the time dimension; Based on the first detection signal characteristics corresponding to the light curtains at the opposite edges of the target area, determine the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges; compare the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges, and determine whether the target area has been invaded by an object.

3. The method according to claim 1, wherein when the target area has been invaded by an object, obtain the detection signals of two groups of light curtains having a specified positional relationship within the target area; analyze the detection signals of the two groups of light curtains to obtain the second detection signal characteristics; based on the second detection signal characteristics, estimating the obstacle range formed by the object within the target area, and thereby adjusting the detection states of the light curtain parts associated with the obstacle range, so as to update the detection signals of all the light curtains is specifically: When the target area is invaded by an object, obtain the detection signals generated by two groups of light curtains perpendicular to each other within the target area; perform spatial variation analysis on the detection signals generated by the two groups of light curtains respectively to obtain second detection signal features; wherein, the second detection signal features refer to the intensity distribution features of the detection signals generated by the light curtains in the spatial dimension. Based on the second detection signal features, determine the detection ranges within the two groups of light curtains where effective detection signals cannot be formed respectively; based on the detection ranges, estimate the obstacle range formed by the object within the target area, and thereby adjust the light emission divergence angles of the internal partial emitters of the light curtains associated with the obstacle range, so as to update the detection signals of all the light curtains.

4. The method according to claim 1, wherein analyze the updated detection signals to obtain the external shape features of the object within the target area; Based on the external shape features, determine whether the object meets the passage restriction conditions of the target area, and thereby adjust the spatial state change operation of the target area, specifically: analyze the updated detection signals to obtain the position information of the distribution of effective detection light rays within the global range of the target area; based on the position information of the distribution of effective detection light rays, determine the external shape features of the part of the object that has invaded the target area; Based on the external shape features, determine the cross-sectional size of the object part; Compare the cross-sectional size with the upper limit of the size of the objects allowed to pass under the passage restriction conditions of the target area, and determine whether the object meets the passage restriction conditions, so as to determine whether to perform a spatial closing operation on the target area.

5. An object tracking and recognition device based on a light curtain, characterized in that, The device includes the following modules: A first detection signal analysis module, configured to obtain the detection signals of the light curtains within the target area, and analyze the detection signals to obtain first detection signal features; An object intrusion judgment module, configured to judge whether the target area is invaded by an object based on the first detection signal features corresponding to the light curtains at specified positions within the target area; A second detection signal analysis module, configured to, when the target area is invaded by an object, obtain the detection signals of two groups of light curtains having a specified positional relationship within the target area; Analyze the detection signals of the two groups of light curtains to obtain second detection signal features; A detection signal update module, configured to estimate the obstacle range formed by the object within the target area based on the second detection signal features, and thereby adjust the detection states of the light curtain parts associated with the obstacle range, so as to update the detection signals of all the light curtains; An object external shape feature determination module, configured to analyze the updated detection signals to obtain the external shape features of the object within the target area; A target area spatial state change operation module, configured to judge whether the object meets the passage restriction conditions of the target area based on the external shape features, and thereby adjust the spatial state change operation of the target area.

6. The device according to claim 5, characterized in that It further includes: The detection signal acquisition and control module is used to collect and analyze the detection signals generated by the light curtain parts located at the corners of the target area, and determine whether the intensity of the detection signals changes within a preset time interval; if so, it controls the acquisition of the detection signals generated by all the light curtains in the target area; if not, it does not control the acquisition of the detection signals generated by all the light curtains in the target area.

7. The device according to claim 6, wherein the first detection signal analysis module is used to acquire the detection signals of the light curtains in the target area, analyze the detection signals, and obtain the first detection signal characteristics, specifically: perform time-domain change analysis on the detection signals generated by all the light curtains respectively to obtain the first detection signal characteristics of all the light curtains respectively; wherein, the first detection signal characteristics refer to the intensity change characteristics of the detection signals generated by the light curtains in the time dimension; the object intrusion judgment module is used to judge whether the target area is invaded by an object based on the first detection signal characteristics corresponding to the light curtains at the specified positions in the target area, specifically: Based on the first detection signal characteristics corresponding to the light curtains at the opposite edges of the target area, determine the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges; compare the occurrence time information of the detection signal intensity change edges corresponding to the light curtains at the opposite edges to judge whether the target area is invaded by an object.

8. The device according to claim 5, wherein the second detection signal analysis module is used to acquire the detection signals of two groups of light curtains with a specified positional relationship in the target area when the target area is invaded by an object; analyze the detection signals of the two groups of light curtains to obtain the second detection signal characteristics, specifically: when the target area is invaded by an object, acquire the detection signals generated by two groups of mutually perpendicular light curtains in the target area respectively; perform spatial domain change analysis on the detection signals generated by the two groups of light curtains respectively to obtain the second detection signal characteristics; wherein, the second detection signal characteristics refer to the intensity distribution characteristics of the detection signals generated by the light curtains in the spatial dimension; the detection signal update module is used to estimate the obstacle range formed by the object in the target area based on the second detection signal characteristics, and adjust the detection states of the light curtain parts associated with the obstacle range accordingly, so as to update the detection signals of all the light curtains, specifically: Based on the second detection signal characteristics, determine the detection ranges within the two groups of light curtains where effective detection signals cannot be formed respectively; based on the detection ranges, estimate the obstacle range formed by the object in the target area, and adjust the light emission divergence angles of some transmitters within the light curtains associated with the obstacle range accordingly, so as to update the detection signals of all the light curtains.

9. The device according to claim 5, wherein the object shape feature determination module is used to analyze the updated detection signals to obtain the shape features of the object in the target area, specifically: Analyze the updated detection signal to obtain the position information of the effective detection light distribution within the global scope of the target area; based on the position information of the effective detection light distribution, determine the external shape characteristics of the object part that has invaded the target area. The target area space change operation module is used to judge whether the object meets the passage restriction conditions of the target area based on the external shape characteristics, so as to adjust the space state change operation of the target area. Specifically: Based on the external shape characteristics, determine the cross-sectional size of the object part; compare the cross-sectional size with the upper limit of the allowable passage object size of the passage restriction conditions of the target area, judge whether the object meets the passage restriction conditions, so as to determine whether to implement a space closing operation on the target area.

10. An elevator, characterized in that, The elevator includes: The light curtain-based device for tracking and identifying objects according to any one of claims 5-9.

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