Escalator passenger fall detection apparatus and method

Abstract

The application discloses an escalator passenger falling detection device, comprising: a pair of sensors, a microwave radar sensor and a falling discrimination controller; the falling discrimination controller is configured to: perform first falling discrimination based on the blocking state time sequence signal of the pair of sensors; perform second falling discrimination based on the motion speed and motion direction signals output by the microwave radar sensor; and output a final falling determination result according to a preset fusion strategy and control the operation of the escalator according to the final falling determination result, according to the results of the first falling discrimination and the second falling discrimination. The application does not collect passenger images, has no privacy controversy and low hardware cost; the two sensors are based on different physical principles and can verify each other, have high reliability and low false alarm rate; a plurality of fusion strategies are provided to adapt to different scenes, and the escalator can be controlled in linkage and in stages to guarantee passenger safety.

Description

Technical Field

[0001] This invention relates to the field of escalator safety technology, specifically to an escalator passenger fall detection device and method based on the fusion of through-beam sensors and microwave sensors. Background Technology

[0002] Escalators are widely used in public places such as shopping malls, train stations, and airports. Incidents of passengers falling while riding escalators due to instability, sudden illness, or loss of balance while carrying belongings are not common. If the escalator is not detected and stopped in time, fallen passengers may be crushed by subsequent steps or downstream passengers, causing secondary injuries.

[0003] Currently, existing technologies for escalator passenger fall detection mainly include the following categories: 1. Fall detection scheme based on computer vision / deep learning For example, patent document CN109726750B discloses a passenger fall detection device and method, which is based on image acquisition and processing, and determines whether a fall has occurred by analyzing changes in passenger posture through visual images. Another example is patent document CN108805093B, which discloses a deep learning-based method for detecting passenger falls on escalators, using a deep learning model to detect passenger fall behavior by acquiring video images of the escalator. Yet another example is patent document CN110472473A, which discloses a method for detecting falls on escalators based on posture estimation, using a human posture estimation algorithm to analyze the positions of key points on the human body and the trajectory of movement to detect falls.

[0004] The aforementioned vision-based solutions have the following drawbacks: they require the installation of high-definition cameras and the use of edge computing units to run image analysis algorithms, resulting in high hardware and deployment costs; they are greatly affected by environmental factors such as lighting conditions, occlusion, and angle, and lack robustness in outdoor or complex lighting escalator scenarios; the collection of passenger images raises privacy concerns; and they do not involve triggering the escalator control system to slow down or stop the escalator after detection.

[0005] 2. Scheme for installing vibration / pressure sensors in the ladder steps For example, patent document CN113916358B discloses a method for escalator hazard monitoring and response based on vibration signal analysis. This method involves setting up a data sampling device array on the escalator step treads to collect vertical vibration signals, using time-domain characteristic values ​​to determine if an object has fallen, and using frequency-domain characteristic values ​​to determine if a person has fallen. Another example is patent document CN107915111B, which discloses a passenger behavior monitoring method and device. This method monitors passenger behavior using pressure sensors installed on the inner wall of the escalator step surface and infrared sensors on both sides of the step surface.

[0006] The sensors in the above-mentioned scheme are installed on the step treads or kick plates, which are moving parts in a cyclic motion. They require independent power supply and wireless communication for each step, resulting in high system complexity and difficult maintenance. The vibration signals are easily interfered with by the mechanical vibration of the escalator itself, leading to a high false alarm rate. Furthermore, it only focuses on behavior monitoring and visual warnings, without addressing the control of escalator deceleration / stop after a fall.

[0007] 3. Passenger detection scheme based on infrared physical sensors For example, patent document CN104058325A discloses an escalator safety warning system that uses through-beam infrared sensors installed on both sides of the escalator. When a passenger enters, the infrared beam is blocked, and the system detects the passenger's presence and issues a warning. Another example is Korean patent document KR102308850B1, which discloses a safety operation control device for escalators and moving walkways. Infrared sensors are installed facing each other on the lower part of the handrails on both sides of the escalator exit side. Combined with a load sensor, the escalator's operating speed is controlled based on the detection results.

[0008] The above solution uses through-beam infrared sensors to detect the presence of passengers (binary detection), which cannot identify changes in posture such as passengers falling; the infrared sensors are only installed at the exit to detect the passengers' descent, not for full-time monitoring; and they do not have fall recognition functionality. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide an escalator passenger fall detection device and method based on the fusion of through-beam sensors and microwave sensors, which addresses the above-mentioned deficiencies of the prior art. The device and method, without collecting passenger images and without privacy disputes, uses two sensors based on different physical principles (beam blocking vs. Doppler effect) to verify each other, which significantly improves the reliability of the system, reduces the false alarm rate, and provides a variety of fusion strategies to adapt to different application scenarios. At the same time, it links with the escalator control system to achieve graded response deceleration and stopping.

[0010] To solve the above-mentioned technical problems, the present invention provides an escalator passenger fall detection device, comprising: a beam sensor, a microwave radar sensor, and a fall detection controller; At least two layers of the through-beam sensors are installed on the inner side panels on both sides of the escalator and arranged vertically in layers, wherein the installation height of the upper through-beam sensor (H1) is 800mm to 1000mm from the tread surface, and the installation height of the lower through-beam sensor (H3) is 100mm to 200mm from the tread surface. The microwave radar sensor is installed on the inner side panel of the escalator and is configured to detect the speed and direction of movement of passengers within the coverage area using the Doppler effect. A fall detection controller, which is electrically connected to both the through-beam sensor and the microwave radar sensor, is configured to: perform a first fall detection based on the occlusion state timing signal of the through-beam sensor; and perform a second fall detection based on the motion speed and motion direction signals output by the microwave radar sensor. Based on the results of the first and second fall detections, the final fall detection result is output according to the preset fusion strategy, and the escalator operation is controlled accordingly.

[0011] Preferably, the fall detection controller is configured to employ any of the following fusion strategies: High sensitivity mode: If a fall is detected by either the first fall detection or the second fall detection, a deceleration and elevator stop response will be triggered. Tiered response mode: If either the first fall detection or the second fall detection determines a fall, a deceleration and audible and visual alarm will be triggered; if both determine a fall, a deceleration and elevator stop response will be triggered. High reliability mode: The deceleration and elevator stop response is triggered only when both the first fall detection and the second fall detection determine that a fall has occurred.

[0012] Preferably, multiple sets of the through-beam sensors are arranged at intervals along the escalator's running direction, with a spacing of 1 to 3 steps between adjacent sets; one microwave radar sensor is installed every 2 meters along the escalator's running direction.

[0013] Preferably, the fall detection controller is configured as follows: The first fall determination is as follows: when the upper through-beam sensor (H1) changes from being blocked to being unblocked within a preset time window (T_th), and the lower through-beam sensor (H3) remains blocked, a fall is determined to have occurred. The second fall determination is as follows: when the rate of change of the downward movement speed of the human body exceeds the preset acceleration threshold (a_th), the movement direction is downward along the escalator, the movement speed exceeds the preset speed threshold (V_th), and the duration exceeds the preset minimum duration (T_min), a fall is determined to have occurred.

[0014] Preferably, the preset time window (T_th) is 0.5s to 2s; the preset acceleration threshold (a_th) is ≥1m / s²; the preset velocity threshold (V_th) is >0.5 m / s and greater than the step running speed; and the preset minimum duration (T_min) is 0.3s.

[0015] Preferably, the fall detection controller is connected to the escalator control system and is configured to issue a deceleration and stop command to the escalator control system after outputting the fall detection result, so that the escalator control system controls the main drive motor to decelerate and brake according to a preset deceleration curve through the frequency converter.

[0016] This invention also provides a method for detecting passenger falls on escalators, comprising the following steps: Step S1: Install at least two layers of through-beam sensors vertically on the inner side panels on both sides of the escalator, such that the installation height of the upper through-beam sensor (H1) is 800mm to 1000mm from the tread surface and the installation height of the lower through-beam sensor (H3) is 100mm to 200mm from the tread surface; and install microwave radar sensors on the inner side panels of the escalator. Step S2: Real-time acquisition of the occlusion status signals of the beam sensors on each layer and the microwave radar sensor signals. The microwave radar sensor uses the Doppler effect to continuously detect the movement speed and direction of passengers within the coverage area. Step S3: Perform a first fall detection based on the occlusion state timing signal of the through-beam sensor, and perform a second fall detection based on the motion speed and motion direction signals output by the microwave radar sensor; Step S4: Based on the results of the first fall detection and the second fall detection, output the final fall detection result according to the preset fusion strategy; Step S5: Based on the final fall determination result, control the escalator to decelerate and stop.

[0017] Preferably, in step S4, the preset fusion strategy is any one of the following: High sensitivity mode: If a fall is detected by either the first fall detection or the second fall detection, a deceleration and elevator stop response will be triggered. Tiered response mode: If either the first fall detection or the second fall detection determines a fall, deceleration and audible and visual alarms will be triggered first; if both determine a fall, then deceleration and elevator stop response will be triggered. High reliability mode: The deceleration and elevator stop response is triggered only when both the first fall detection and the second fall detection determine that a fall has occurred.

[0018] Preferably, in step S3, the first fall detection includes: Monitor whether the occlusion status of the upper-layer through-beam sensor (H1) changes from occluded to unoccluded within a preset time window (T_th); A fall is determined to have occurred when the upper through-beam sensor (H1) changes from being blocked to being unblocked within the preset time window, while the lower through-beam sensor (H3) remains blocked.

[0019] Preferably, in step S3, the second fall detection includes: A fall is determined when the rate of change of a person's downward movement speed exceeds a preset acceleration threshold (a_th), the movement direction is downward along the escalator, the movement speed exceeds a preset speed threshold (V_th), and the duration exceeds a preset minimum duration (T_min).

[0020] Preferably, the preset time window (T_th) is 0.5s to 2s.

[0021] Preferably, the preset acceleration threshold (a_th) is ≥1 m / s², the preset velocity threshold (V_th) is >0.5 m / s and greater than the step running speed, and the preset minimum duration (T_min) is 0.3 s.

[0022] Preferably, multiple sets of the through-beam sensors are arranged at intervals along the escalator's running direction, with the distance between two adjacent sets being 1 to 3 steps; one microwave radar sensor is installed every 2 meters along the escalator's running direction.

[0023] Preferably, in step S5, the escalator control system controls the main drive motor to decelerate according to an S-shaped deceleration curve via a frequency converter, with the deceleration rate not exceeding 1.0 m / s². After decelerating to a low speed, the working brake is activated to bring the escalator to a complete stop.

[0024] Preferably, the escalator enters a locked state after stopping and can only resume operation after being manually reset; and in step S5, an audible and visual alarm and a voice alarm are activated at the same time as the deceleration and escalator stop command is issued.

[0025] Compared with the prior art, the present invention has the following beneficial effects: 1. Low cost and no privacy concerns: By using through-beam sensors and microwave radar sensors instead of cameras, passenger images are not collected, thus avoiding privacy concerns. The system hardware cost is approximately 30% to 50% of that of vision solutions, and no edge computing devices are required.

[0026] 2. Fixed components are easy to install and maintain: Both types of sensors are installed on the inner side plate (fixed components) of the escalator, and can be directly powered by fixed lines and wired communication. There is no need to solve the problem of independent power supply and wireless communication for the moving steps. The system has low complexity and is easy to maintain.

[0027] 3. Dual-Principle Fusion and High Reliability: The through-beam sensor and microwave sensor operate based on different physical principles (beam obstruction vs. Doppler effect), complementing and verifying each other. The through-beam sensor excels at detecting changes in obstruction caused by sudden changes in human height, while the microwave sensor excels at detecting sudden changes in speed and direction of movement. The fusion of the two can cover the detection blind spots of a single sensor, significantly improving system reliability and reducing false alarm rate.

[0028] 4. Multiple fusion strategies to adapt to different scenarios: Three fusion strategies are provided: high-sensitivity mode, tiered response mode, and high-reliability mode, which can be flexibly selected according to the security requirements and operational efficiency needs of the application scenario. For example, high-sensitivity mode is suitable for hospitals and elderly activity centers; tiered response mode is suitable for densely populated places such as shopping malls and train stations; and high-reliability mode is suitable for scenarios sensitive to false alarm rates.

[0029] 5. Tiered response, balancing safety and efficiency: In tiered response mode, any sensor that detects a fall will trigger deceleration and an audible and visual alarm. Only when both are detected will the escalator stop completely. This ensures that fallen passengers receive timely response and avoids frequent escalator stops due to false alarms, which would affect operational efficiency.

[0030] 6. Strong environmental adaptability: The through-beam sensor is not affected by lighting conditions, and the microwave sensor has the ability to penetrate dust and water mist. The combination of the two can be used in various complex operating environments such as outdoor, underground passage, and humid environments.

[0031] 7. Interlocked escalator control ensures safety: Upon detecting a fall, the escalator control system is immediately activated to decelerate and stop the escalator according to an S-shaped deceleration curve. At the same time, audible and visual alarms and voice warnings are activated, and the escalator enters a locked state that requires manual reset to avoid secondary injury. Detailed Implementation

[0032] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can fully understand other advantages and technical effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and the details in this specification can also be applied based on different viewpoints, with various modifications or changes made without departing from the overall design concept of the invention. It should be noted that, unless otherwise specified, the following embodiments and features can be combined with each other. The following exemplary embodiments of the present invention can be implemented in many different forms and should not be construed as being limited to the specific embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art. Example

[0033] This embodiment provides an escalator passenger fall detection device, including a beam sensor, a microwave radar sensor, and a fall detection controller.

[0034] At least two layers of through-beam sensors are installed on the inner side panels of both sides of the escalator, arranged vertically in layers. This embodiment uses two layers of through-beam infrared sensors: The upper-level through-beam sensor H1 is installed at a height of 900mm from the tread of the step, corresponding to the waist position of the passenger (generally the value range is 800mm to 1000mm). The lower-level through-beam sensor H3 is installed at a height of 150mm from the tread of the step, corresponding to the passenger's ankle position (generally within the range of 100mm to 200mm).

[0035] Each layer of the through-beam sensor consists of an infrared transmitter mounted on one inner side panel and a receiver mounted on the opposite inner side panel, forming a detection beam spanning the width of the step. When a passenger is standing on a step, the infrared beam is blocked by the body, and the receiver outputs a blocked status signal; when there are no passengers or when a passenger is lying down and there is no obstruction at that height, the receiver outputs an unblocked status signal. The through-beam sensor is powered by a fixed line and communicates with the fall detection controller via a wired connection.

[0036] Furthermore, this embodiment can also employ a three-layer through-beam sensor layout, namely, adding a middle through-beam sensor H2, 450mm (range 400mm~500mm) from the step surface, corresponding to the passenger's knee position. The fall detection controller identifies changes in human posture based on the temporal changes in the occlusion states of the three layers of through-beam sensors: during a fall, the occlusion disappears in the order H1→H2→H3, and the time interval between the disappearance of each layer of occlusion has a unique pattern specific to falls, thereby improving the accuracy of the first fall detection.

[0037] A microwave radar sensor is installed on the inner panel of the escalator and is configured to detect the speed and direction of movement of passengers within the coverage area using the Doppler effect. In this embodiment, the microwave radar sensor operates at a frequency of 24 GHz (or the commonly used 5.8 GHz band), and the coverage distance of a single microwave radar sensor is approximately 2 to 3 meters. The microwave radar sensor is powered by a fixed line and communicates with the fall detection controller via a wired connection.

[0038] Multiple sets of through-beam sensors are spaced apart along the escalator's running direction, with a spacing of 1 to 3 steps (approximately 400mm to 1200mm) between adjacent sets. In this embodiment, a set of through-beam sensors is installed approximately every 800mm (approximately 2 steps), striking a balance between full coverage and control costs. Microwave radar sensors are installed approximately every 2m along the escalator's running direction, achieving full coverage.

[0039] The fall detection controller is electrically connected to both a beam sensor and a microwave radar sensor, and is configured as follows: The first fall detection method is based on the timing signal of the occlusion state of the through-beam sensor. A fall is determined when the occlusion state of the upper through-beam sensor H1 changes from occluded to unoccluded within a preset time window T_th, while the lower through-beam sensor H3 remains occluded. In this embodiment, the preset time window T_th = 1.5s (range 0.5s to 2s).

[0040] The second fall detection method is based on the motion speed and direction signals output by the microwave radar sensor. A fall is determined when the rate of change of the downward motion speed of the human body exceeds a preset acceleration threshold a_th, the motion direction is downward along the escalator, the motion speed exceeds a preset speed threshold V_th, and the duration exceeds a preset minimum duration T_min. In this embodiment, a_th = 1 m / s² (≥ 1 m / s²), V_th = 0.5 m / s (> 0.5 m / s and greater than the step speed), and T_min = 0.3 s (corresponding to claim 5).

[0041] Fusion Strategy: Based on the results of the first and second fall detections, the final fall determination result is output according to a preset fusion strategy. The fall detection controller is configured to use any of the following fusion strategies: High-sensitivity mode: The elevator will decelerate and stop when either the first or second fall detection is detected as a fall; suitable for scenarios with extremely high safety requirements, such as hospitals and nursing homes.

[0042] Tiered response mode: If either the first fall detection or the second fall detection is detected as a fall, deceleration and audible and visual alarms are triggered; if both are detected as a fall, deceleration and elevator stop are triggered. This mode is suitable for scenarios with high pedestrian traffic, such as shopping malls and train stations, where a balance between safety and operational efficiency is required.

[0043] High reliability mode: The deceleration and elevator stop response is triggered only when both the first and second fall detection methods determine a fall; suitable for scenarios sensitive to false alarm rates.

[0044] This embodiment defaults to a tiered response mode: when either sensor detects a fall, it first triggers deceleration and an audible and visual alarm, and the escalator begins to decelerate at a preset speed but does not come to a complete stop; when both sensors detect a fall, it triggers a complete stop, and the working brake actuates to bring the escalator to a complete stop. If the first fall is detected as a fall but the second fall is detected as a fall (possibly a false alarm or the microwave sensor is not covered), the escalator decelerates but does not come to a complete stop. Operation can resume after maintenance personnel or passengers confirm that there is no abnormality, thus avoiding frequent complete stops of the escalator due to false alarms.

[0045] The fall detection controller is connected to the escalator control system and is configured to send a deceleration and stop command to the escalator control system after outputting the fall detection result, so that the escalator control system controls the main drive motor to decelerate and brake according to a preset deceleration curve through the frequency converter.

[0046] In this embodiment, the escalator control system uses a frequency converter to control the main drive motor to decelerate according to an S-shaped deceleration curve, with a deceleration rate not exceeding 1.0 m / s². After the frequency converter decelerates to a low speed, the working brake activates, completely stopping the escalator. After stopping, the escalator enters a locked state, requiring on-site safety confirmation and manual reset by maintenance personnel before operation can resume. Simultaneously with issuing the deceleration and stop command, the fall detection controller triggers an audible and visual alarm and a voice alarm (such as "Emergency, escalator is about to decelerate").

[0047] Working principle of the device When a passenger is standing and riding the escalator normally, their body simultaneously blocks the beams of light from both the upper H1 and lower H3 escalators, causing both sensors to be blocked. The speed of human movement detected by the microwave radar sensor is close to the escalator's operating speed (baseline state). When a passenger falls: On the through-beam sensor side: As the human body descends rapidly, the upper layer H1 beam is no longer blocked (the blocking state changes from blocked to unblocked), while the lower body still blocks the lower layer H3 beam after the human body falls down (maintaining the blocked state), forming a timing pattern of "upper layer blocking disappears rapidly, lower layer remains blocked", triggering the first fall detection.

[0048] On the microwave sensor side: When the human body accelerates downward relative to the escalator, the microwave radar sensor 5 detects a sudden increase in the human body's speed and downward direction based on the Doppler effect, which meets the acceleration threshold, speed threshold and duration conditions, triggering the second fall detection.

[0049] The two sensors operate based on different physical principles (beam blocking vs. Doppler effect), complementing and verifying each other. They can cover the detection blind spots of a single sensor, significantly improving system reliability and reducing false alarm rate. Example

[0050] This embodiment provides a method for detecting passenger falls on escalators, including the following steps: Step S1: Install at least two layers of through-beam sensors vertically on the inner side panels 1 on both sides of the escalator, such that the installation height of the upper through-beam sensor H1 is 800mm to 1000mm from the tread surface and the installation height of the lower through-beam sensor H3 is 100mm to 200mm from the tread surface; and install microwave radar sensors on the inner side panels of the escalator.

[0051] Furthermore, multiple sets of through-beam sensors are spaced apart along the escalator's running direction, with the distance between adjacent sets being 1 to 3 steps (approximately 400mm to 1200mm); microwave radar sensors are installed approximately every 2m along the escalator's running direction. In this embodiment, H1 is 900mm from the step surface, H3 is 150mm from the step surface, and a set of through-beam sensors is installed approximately every 800mm along the running direction, while a microwave radar sensor is installed approximately every 2m.

[0052] Step S2: Real-time acquisition of the obstruction status signals of the beam sensors on each layer and the microwave radar sensor signals. The microwave radar sensor uses the Doppler effect to continuously detect the speed and direction of movement of passengers within the coverage area.

[0053] When passengers are standing and riding the escalator normally, both H1 and H3 are blocked; the speed of human movement detected by the microwave radar sensor is close to the speed of the escalator.

[0054] Step S3: Perform a first fall detection based on the occlusion state timing signal of the through-beam sensor, and perform a second fall detection based on the motion speed and motion direction signals output by the microwave radar sensor.

[0055] The first criteria for judging a fall include: Monitor whether the occlusion state of the upper-layer through-beam sensor H1 changes from occluded to unoccluded within a preset time window T_th; in this embodiment, T_th = 1.5s (value range 0.5s to 2s). A fall is determined to have occurred when the upper-layer through-beam sensor H1 changes from being blocked to being unblocked within a preset time window T_th, while the lower-layer through-beam sensor H3 remains blocked.

[0056] The second criterion for falling includes: A fall is determined to have occurred when the rate of change of the downward movement speed of a human body exceeds the preset acceleration threshold a_th, the movement direction is downward along the escalator, the movement speed exceeds the preset speed threshold V_th, and the duration exceeds the preset minimum duration T_min. In this embodiment, a_th = 1 m / s² (≥ 1 m / s²), V_th = 0.5 m / s (> 0.5 m / s and greater than the speed of the steps), and T_min = 0.3 s.

[0057] To avoid misinterpreting normal passenger movements such as bending over or turning as falls, the second fall detection system employs a triple-condition approach: an acceleration threshold, a velocity threshold, and a minimum duration. A fall is only detected when all three conditions are met simultaneously, effectively reducing the false alarm rate. The system uses the passenger's normal standing speed, which is close to the escalator's operating speed, as a baseline. A fall detection is triggered when a sudden increase in the human body's speed relative to the escalator, particularly if the direction is downward.

[0058] Step S4: Based on the results of the first fall detection and the second fall detection, output the final fall detection result according to the preset fusion strategy.

[0059] The default fusion strategy is any of the following: High-sensitivity mode: The elevator will decelerate and stop when either the first or second fall detection is detected. It is suitable for scenarios with extremely high safety requirements, such as hospitals and nursing homes, and will sacrifice some operating efficiency to ensure passenger safety to the greatest extent.

[0060] Tiered response mode: If either the first or second fall detection method determines a fall, deceleration and audible and visual alarms will be triggered first; if both methods determine a fall, then deceleration and elevator stop will be triggered. This mode is suitable for scenarios with high pedestrian traffic, such as shopping malls and train stations, where a balance between safety and operational efficiency is required.

[0061] High reliability mode: The deceleration and elevator stop response is triggered only when both the first and second fall detection methods determine a fall; suitable for scenarios sensitive to false alarm rate, the false alarm rate is reduced to the greatest extent by mutual verification of the two principles.

[0062] This embodiment uses a hierarchical response mode by default.

[0063] Step S5: Based on the final fall assessment result, control the escalator to slow down and stop.

[0064] Furthermore, the escalator control system uses a frequency converter to control the main drive motor to decelerate according to an S-shaped deceleration curve, with the deceleration rate not exceeding 1.0 m / s². After decelerating to a low speed, the working brake is activated to bring the escalator to a complete stop.

[0065] Furthermore, after the escalator stops, it enters a locked state and can only be restarted after manual reset; and at the same time as issuing the deceleration and stop command, an audible and visual alarm and a voice alarm are activated.

[0066] In this embodiment, upon confirmation of a fall, the fall detection controller immediately sends a deceleration and stop command to the escalator control system, simultaneously activating audible and visual alarms and a voice warning (such as "Emergency, escalator is about to decelerate"). The escalator control system uses a frequency converter to control the main drive motor to decelerate according to an S-shaped deceleration curve, with a deceleration rate not exceeding 1.0 m / s². After the frequency converter decelerates to a low speed, the working brake activates, completely stopping the escalator. After stopping, the escalator enters a locked state, requiring maintenance personnel to confirm safety on-site and manually reset it before operation can resume.

[0067] The present invention has been described in detail above through specific embodiments and examples, but these are not intended to limit the invention. Many modifications and improvements can be made by those skilled in the art without departing from the principles of the invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A passenger fall detection device for escalators, characterized in that, include: Through-beam sensor, microwave radar sensor, and fall detection controller; At least two layers of the aforementioned through-beam sensors are installed on the inner side panels on both sides of the escalator and arranged vertically in layers, wherein the installation height of the upper through-beam sensor (H1) is 800mm to 1000mm from the tread surface of the step, and the installation height of the lower through-beam sensor (H3) is 100mm to 200mm from the tread surface of the step. The microwave radar sensor is installed on the inner side panel of the escalator and is configured to detect the speed and direction of movement of passengers within the coverage area using the Doppler effect. A fall detection controller, which is electrically connected to both the through-beam sensor and the microwave radar sensor, is configured to: perform a first fall detection based on the occlusion state timing signal of the through-beam sensor; and perform a second fall detection based on the motion speed and motion direction signals output by the microwave radar sensor. Based on the results of the first and second fall detections, the final fall detection result is output according to the preset fusion strategy, and the escalator operation is controlled accordingly.

2. The escalator passenger fall detection device according to claim 1, characterized in that, The fall detection controller is configured to employ any of the following fusion strategies: High sensitivity mode: If a fall is detected by either the first fall detection or the second fall detection, a deceleration and elevator stop response will be triggered. Tiered response mode: If either the first fall detection or the second fall detection determines a fall, a deceleration and audible and visual alarm will be triggered; if both determine a fall, a deceleration and elevator stop response will be triggered. High reliability mode: The deceleration and elevator stop response is triggered only when both the first fall detection and the second fall detection determine that a fall has occurred.

3. The escalator passenger fall detection device according to claim 1, characterized in that, The through-beam sensors are arranged in multiple sets at intervals along the escalator's running direction, with the spacing between adjacent sets being 1 to 3 steps; the microwave radar sensors are installed approximately every 2 meters along the escalator's running direction.

4. The escalator passenger fall detection device according to claim 1, characterized in that, The fall detection controller is configured as follows: The first fall determination is as follows: when the upper through-beam sensor (H1) changes from being blocked to being unblocked within a preset time window (T_th), and the lower through-beam sensor (H3) remains blocked, a fall is determined to have occurred. The second fall determination is as follows: when the rate of change of the downward movement speed of the human body exceeds the preset acceleration threshold (a_th), the movement direction is downward along the escalator, the movement speed exceeds the preset speed threshold (V_th), and the duration exceeds the preset minimum duration (T_min), a fall is determined to have occurred.

5. The escalator passenger fall detection device according to claim 4, characterized in that, The preset time window (T_th) is 0.5s to 2s; the preset acceleration threshold (a_th) is ≥1 m / s²; the preset velocity threshold (V_th) is >0.5 m / s and greater than the speed of the ladder running; and the preset minimum duration (T_min) is 0.3s.

6. The escalator passenger fall detection device according to claim 1, characterized in that, The fall detection controller is connected to the escalator control system and is configured to send a deceleration and stop command to the escalator control system after outputting the fall detection result, so that the escalator control system controls the main drive motor to decelerate and brake according to a preset deceleration curve through the frequency converter.

7. A method for detecting passenger falls on escalators, characterized in that, Includes the following steps: Step S1: Install at least two layers of through-beam sensors vertically on the inner side panels on both sides of the escalator, such that the installation height of the upper through-beam sensor (H1) is 800mm to 1000mm from the tread surface and the installation height of the lower through-beam sensor (H3) is 100mm to 200mm from the tread surface; and install microwave radar sensors on the inner side panels of the escalator. Step S2: Real-time acquisition of the occlusion status signals of the beam sensors on each layer and the microwave radar sensor signals. The microwave radar sensor uses the Doppler effect to continuously detect the movement speed and direction of passengers within the coverage area. Step S3: Perform a first fall detection based on the occlusion state timing signal of the through-beam sensor, and perform a second fall detection based on the motion speed and motion direction signals output by the microwave radar sensor; Step S4: Based on the results of the first fall detection and the second fall detection, output the final fall detection result according to the preset fusion strategy; Step S5: Based on the final fall determination result, control the escalator to decelerate and stop.

8. The escalator passenger fall detection method according to claim 7, characterized in that, In step S4, the preset fusion strategy is any one of the following: High sensitivity mode: If a fall is detected by either the first fall detection or the second fall detection, a deceleration and elevator stop response will be triggered. Tiered response mode: If either the first fall detection or the second fall detection determines a fall, deceleration and audible and visual alarms will be triggered first; if both determine a fall, then deceleration and elevator stop response will be triggered. High reliability mode: The deceleration and elevator stop response is triggered only when both the first fall detection and the second fall detection determine that a fall has occurred.

9. The escalator passenger fall detection method according to claim 7, characterized in that, In step S3, the first fall determination includes: Monitor whether the occlusion status of the upper-layer through-beam sensor (H1) changes from occluded to unoccluded within a preset time window (T_th); A fall is determined to have occurred when the upper through-beam sensor (H1) changes from being blocked to being unblocked within the preset time window, while the lower through-beam sensor (H3) remains blocked.

10. The escalator passenger fall detection method according to claim 7, characterized in that, In step S3, the second fall detection includes: A fall is determined when the rate of change of a person's downward movement speed exceeds a preset acceleration threshold (a_th), the movement direction is downward along the escalator, the movement speed exceeds a preset speed threshold (V_th), and the duration exceeds a preset minimum duration (T_min).

11. The method for detecting passenger falls on escalators according to claim 9, characterized in that, The preset time window (T_th) is 0.5s to 2s.

12. The escalator passenger fall detection method according to claim 10, characterized in that, The preset acceleration threshold (a_th) is ≥1 m / s², the preset velocity threshold (V_th) is >0.5 m / s and greater than the step running speed, and the preset minimum duration (T_min) is 0.3s.

13. The escalator passenger fall detection method according to claim 7, characterized in that, The through-beam sensors are arranged in multiple sets at intervals along the escalator's running direction, with the distance between two adjacent sets being 1 to 3 steps; the microwave radar sensors are installed approximately every 2 meters along the escalator's running direction.

14. The escalator passenger fall detection method according to claim 7, characterized in that, In step S5, the escalator control system controls the main drive motor to decelerate according to an S-shaped deceleration curve via a frequency converter. The deceleration rate does not exceed 1.0 m / s². After decelerating to a low speed, the working brake is activated to bring the escalator to a complete stop.

15. The escalator passenger fall detection method according to claim 7, characterized in that, After the escalator stops, it enters a locked state and can only be restarted after manual reset; and in step S5, the audible and visual alarm and voice alarm are activated at the same time as the deceleration and escalator stop command is issued.