A hydraulic climbing formwork monitoring method and wedge-shaped fall arrestor based on three criteria: tilt angle, acceleration, and velocity.

Abstract

This invention discloses a hydraulic climbing formwork monitoring method and a wedge-shaped fall arrestor based on three criteria: tilt, acceleration, and velocity. The monitoring method includes: deploying tilt, displacement, and acceleration sensors at key parts of the climbing formwork to collect data in real time and upload it to a cloud monitoring platform; and implementing graded early warning based on a three-level threshold system. When any of the trigger conditions of tilt and acceleration, velocity and acceleration, or velocity discreteness and acceleration are met, a red emergency state is determined, and a trigger command is issued to the wedge-shaped fall arrestor. The wedge-shaped fall arrestor includes a butterfly spring assembly, a stress sensor, a solenoid valve, a wedge brake, a reset mechanism, and a braking rail. It adopts the principle of "spring energy storage, electromagnetic triggering, and wedge self-locking," and monitors the butterfly spring status in real time through the stress sensor to ensure reliable braking force. This invention achieves multi-dimensional real-time monitoring and active safety protection throughout the entire process of climbing formwork descent, effectively solving the safety problem of reverse walking conditions during construction near existing railway piers.

Description

Technical Field

[0001] This invention relates to the field of bridge pier and building construction technology, and more specifically, to a hydraulic climbing formwork monitoring method and a wedge-shaped anti-fall device for the construction of high piers near existing railways. Technical Background

[0002] Hydraulic climbing formwork technology has become the mainstream construction method for high and ultra-high bridge piers due to its advantages such as strong self-climbing ability, high construction efficiency, and good structural adaptability. As my country's high-speed railway network extends to mountainous areas and densely populated urban areas, newly built railway lines inevitably need to pass near existing operating railways, resulting in a large number of high-pier bridges needing to be constructed in narrow spaces adjacent to existing lines.

[0003] Working near an existing railway presents unique safety challenges: constrained by railway safety clearances and the protection range of the overhead contact line, the side closest to the existing line cannot accommodate the positioning and rotation requirements of large lifting equipment. Therefore, after the pier columns are poured to the design elevation, the hydraulic climbing formwork system cannot be dismantled and removed from the pier top using conventional methods; it must be moved downwards as a whole to a safe area at the bottom of the pier before dismantling can proceed. This forced "reverse movement" necessitates the climbing formwork descending step by step from a height of hundreds of meters, placing even higher demands on the safety of the hydraulic climbing formwork system.

[0004] However, existing hydraulic climbing formwork technology has significant shortcomings when dealing with reverse travel conditions. Firstly, traditional fall arrestors are primarily designed for the main climbing direction, and their triggering logic relies on gravity or spring action to engage the pawls with the guide rail teeth. During reverse travel, the fall arrestor's movement direction is opposite to or at an angle to the direction of gravity, making it difficult to reliably position and prone to failure modes such as jamming and incomplete rebound. In actual operation, verification of the fall arrestor's status can only rely on intermittent inspections such as manual visual inspection, making real-time perception and dynamic verification impossible during continuous descents lasting several hours, resulting in blind spots in protection.

[0005] Secondly, existing climbing formwork monitoring systems mostly focus on controlling the synchronization of the climb, typically using displacement sensors to monitor the height difference between each machine position to ensure construction accuracy. However, they have not yet incorporated dynamic safety parameters during the descent of the climbing formwork into the fall prevention trigger criteria. When the climbing formwork exhibits signs of loss of control, such as excessive tilt or sudden acceleration during descent due to uneven load or internal leakage in the hydraulic cylinders, the existing system cannot actively trigger the fall prevention device at the critical moment, thus missing the best opportunity for safety intervention.

[0006] Therefore, it is urgent to develop a fall protection device specifically adapted to reverse walking conditions, and to establish an intelligent monitoring system with tilt and acceleration as the core criteria to realize real-time perception of fall protection status and proactive intervention in movement risks, so as to solve the safety problem of climbing frame dismantling during the construction of high piers near existing railways. Summary of the Invention

[0007] The purpose of this invention is to provide a hydraulic climbing formwork monitoring method and a wedge-shaped anti-fall device based on three criteria: tilt, acceleration and velocity, so as to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: On the one hand, this invention provides a hydraulic climbing formwork monitoring method based on three criteria: tilt angle, acceleration, and velocity, comprising the following steps: S1. Sensor System Deployment and Data Acquisition. Inclination sensors, displacement sensors, and acceleration sensors are deployed at key locations on the hydraulic climbing formwork. All sensors are connected to the Internet of Things (IoT) via a data acquisition device and uploaded to the cloud monitoring platform in real time.

[0009] S2. Real-time calculation of motion state parameters. After receiving the raw data, the monitoring platform performs real-time calculation of motion state parameters, including: calculating the overall tilt of the climbing frame and the descent speed of each station. Overall downward speed Machine position speed dispersion and downward composite acceleration .

[0010] Furthermore, the overall tilt angle is , These are the measured values ​​of the lateral and longitudinal tilt angles (unit: degrees).

[0011] The downlink speed of each machine station is: , For the first i Each camera position t Cumulative displacement at time intervals Sampling frequency; overall speed v ( t This represents the weighted average speed of each machine position. For the first i Each camera position Cumulative displacement over time; The machine position speed dispersion is: ; For the first i The instantaneous speed of each camera position, from Find out, v ( t This is a weighted average of the speeds of multiple camera positions. n Number of machine positions; The downlink synthetic acceleration is , where is the measured value of vertical acceleration (unit: m / s²), and g is the acceleration due to gravity.

[0012] S3. Graded Early Warning and Fall Protection Trigger. Based on a preset three-level threshold system, single parameters are judged. When any parameter reaches the warning threshold, a yellow warning is triggered; when it reaches the alarm threshold, an orange alarm is triggered and automatic deceleration is initiated. When the multi-parameter fusion triggering conditions are met, a red emergency state is determined, and a trigger command is sent to the fall protection device.

[0013] Furthermore, tilt Normal <0.3°, 0.5°> Warning: ≥0.3°, 0.8°> Alarm ≥0.5° Trigger angle ≥0.8°; Overall speed Normal <0.8 , > Warning ≥ 0.8 , Warning > Machine position speed dispersion Normal velocity dispersion <0.1m / min, 0.15m / min> Warning ≥0.1m / min, velocity dispersion Alarm speed ≥ 0.15 m / min; Downward composite acceleration Normal >-0.2g, synthetic acceleration Warning ≤ -0.2g, synthetic acceleration Alarm ≤ -0.3g, composite acceleration Trigger ≤ -0.5g and t ≥ 200ms.

[0014] Furthermore, the multi-parameter fusion triggering conditions include the following three modes: Mode 1: Tilt and Acceleration Fusion Trigger ; Mode 2: Velocity and acceleration fusion trigger ; Mode 3: Velocity and acceleration fusion trigger ; The combined trigger signal is: In-Mode=Mode1∪Mode2∪Mode3; The specific conditions for triggering the graded early warning and fall prevention are: yellow warning, orange alarm, and red emergency (trigger level).

[0015] On the other hand, the present invention provides a wedge-shaped fall arrest device for the above-mentioned monitoring method, including a butterfly spring assembly, a stress sensor, a solenoid valve, a wedge brake, a reset mechanism, and a brake rail.

[0016] The disc spring assembly is composed of multiple disc springs stacked together and installed inside the wedge-shaped fall arrestor housing. One end is fixed to the front end of the wedge-shaped fall arrestor housing, and the other end abuts against the rear seat base plate. By adjusting the reset bolt at the front end position, the disc spring assembly is brought to the designed compression state to store elastic potential energy.

[0017] The stress sensor is installed between the rear seat base plate and the wedge brake to sense the compression force of the spring assembly in real time.

[0018] The solenoid valve is installed on the side of the wedge-shaped fall arrestor housing. Its armature is connected to a high-strength limiting pin, and the pin axis coincides with the wedge-shaped brake groove axis on the side of the wedge brake. The solenoid valve adopts a power-off locking and power-on release mode.

[0019] The wedge brake consists of a friction pad, a wedge brake slot, limiting and guiding balls, and a wedge brake block. The wedge brake block is a high-strength steel component, with its rear end in contact with a stress sensor and its front end fitted with a replaceable friction pad.

[0020] The braking rail is a dedicated braking rail independent of the climbing scaffold rail, or the climbing scaffold rail can be used directly as the braking rail. The surface of the braking rail is hardened, has high wear resistance, and forms a stable friction pair with the friction pads. Limiting and positioning rails are set inside the braking rail for fixing and guiding the positioning bracket of the wedge-shaped fall arrestor.

[0021] The reset mechanism includes a reset bolt and a reset screw. By rotating the reset bolt, the disc spring assembly is compressed, thereby pulling the wedge brake back to its initial position.

[0022] The tilt angle of the wedge brake (31) a The friction coefficient of friction plate (311) is between 30° and 45°. μ ≥0.4; the preload of the disc spring assembly (36) is designed to be ≥0.4. Maximum elasticity satisfies ,in For the required braking force, G This represents the total weight of the climbing scaffold. k s For safety factor (take 1.5-2.0).

[0023] Braking force when braking is triggered The stress sensor monitors the thrust of the disc spring assembly (36) in real time. And calculate the actual braking force ,like The system will then determine that the braking force is insufficient and trigger a supplementary alarm.

[0024] The fall arrestor also includes the following redundant safety design: a dual solenoid valve parallel design, where the lock can be released by the action of either solenoid valve.

[0025] Furthermore, the friction pad material is a high friction coefficient composite material with a dry friction coefficient ≥0.4.

[0026] Furthermore, the design preload of the disc spring assembly... With pre-compression satisfy Where k is the total stiffness coefficient of the spring assembly; and the ultimate elastic force of the spring assembly under maximum compression. satisfy .in For the required braking force G is the total weight of the climbing scaffold. k s For safety factor (take 1.5-2.0).

[0027] Furthermore, when the fall arrestor triggers braking, the braking force and the thrust of the disc spring assembly satisfy the following:

[0028] Stress sensors monitor the thrust of the disc spring assembly in real time. The system calculates the actual braking force in real time according to the changes. and with In comparison, if If insufficient braking force is detected, the system will trigger a supplementary alarm and prompt manual intervention.

[0029] Beneficial effects of the present invention 1. This invention adopts a three-criterion fusion monitoring of tilt, speed and acceleration to achieve multi-dimensional real-time perception of the climbing frame descent process. It can promptly detect abnormal trends and actively intervene through three-level hierarchical early warning, effectively avoiding the blind spot of traditional monitoring systems that only focus on synchronization.

[0030] 2. The fall arrestor proposed in this invention adopts the principle of "spring energy storage, electromagnetic triggering, and wedge self-locking". The stress sensor monitors the spring state in real time to ensure that the device is always in a reliable standby state; the electromagnetic valve responds quickly (≤50ms), ensuring the timeliness of emergency braking.

[0031] 3. This invention is designed for reverse travel conditions, which solves the problem that traditional fall arrest devices are difficult to reliably position during descent, and greatly improves the inherent safety level of construction near existing lines. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the monitoring method of the present invention; Figure 2 This is a schematic diagram of the overall structure of the present invention; Figure 3This is a schematic diagram of the wedge-shaped brake positioning bracket and track structure of the present invention; Figure 4 This is a schematic diagram of the installation of the wedge brake of the present invention; Figure 5 This is a detailed structural diagram of the wedge-shaped brake of the present invention.

[0033] The reference numerals in the attached figures are: 1. Climbing formwork; 11. Load-bearing tripod upright; 2. Wedge-shaped fall arrestor positioning bracket; 21. Wedge-shaped fall arrestor positioning bolt; 22. Wedge-shaped fall arrestor positioning steel box; 3. Wedge-shaped fall arrestor; 31. Wedge-shaped brake; 311. Friction pad; 312. Wedge-shaped brake slot; 313. Limiting and guiding ball bearing; 32. Solenoid valve; 321. Upper iron core and limiting pad; 322. Return spring; 323. Armature; 324. High-strength limiting pin; 33. Return bolt; 34. Return screw; 35. Stress sensor; 36. Disc spring assembly; 37. Wedge-shaped fall arrestor housing; 371. Rear seat base plate; 4. Hydraulic climbing formwork assembly; 41. First reversing box; 42. Second reversing box; 43. Reverse travel cylinder; 5. Braking rail; 51. Limiting and positioning slide rail; 6. Concrete. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be noted that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0035] Example 1: Implementation of the monitoring method This embodiment provides a hydraulic climbing formwork monitoring method based on three criteria: tilt angle, acceleration, and velocity. For example... Figure 1 As shown, it includes the following steps: S1. Sensor System Deployment and Data Acquisition. Tilt sensors are installed on the main beam of the load-bearing frame at each machine position, with the sensitive axis parallel to the main axis and vibration reduction measures implemented. Displacement sensors are installed at the hydraulic cylinders at each machine position to monitor cumulative displacement in real time. Acceleration sensors are installed at the four corners and center of gravity of the frame, close to the load-bearing structure to avoid vibration. All sensors are connected to the data acquisition unit via bus, synchronously acquiring data at 50Hz, and uploading it to the cloud monitoring platform via the Internet of Things, while also backing it up locally.

[0036] S2. Mathematical definition and real-time calculation of motion state parameters. After removing gross errors, applying moving average filtering, and correcting for zero drift, the monitoring platform calculates the overall tilt of the climbing scaffold in real time. Downlink speed of each camera position Overall downward speed Machine position speed dispersion and downward composite acceleration These are the five core motion state parameters.

[0037] The overall tilt for , and These are the measured values ​​of the lateral and longitudinal tilt angles (unit: degrees).

[0038] The downlink speed of each machine position for , For the first i Each camera position t Cumulative displacement at time intervals The sampling frequency. The overall downlink speed. The weighted average of the speeds at each machine position is taken. The machine position speed dispersion... for The downlink composite acceleration is , ρ is the measured value of vertical acceleration (unit: m / s²), and g is the acceleration due to gravity.

[0039] S3. Graded Early Warning and Fall Prevention Trigger Judgment. Based on a large amount of engineering measurement data and combined with the special safety requirements of construction near existing railways, a three-level early warning system is established: yellow warning, orange alarm (intervention level), and red emergency (trigger level).

[0040] The conditions for triggering the yellow alert are as follows: , Meeting any of the above conditions will trigger an on-site audio-visual alert, reminding the operator to pay attention.

[0041] The triggering conditions for the orange alarm (intervention level) are as follows: , When any of the above conditions are met, the system will automatically reduce the hydraulic system flow, limit the downward speed, and send an alarm message to the project department.

[0042] The red emergency trigger conditions are divided into three modes: Mode 1 is severe tilting and stalling during a descent. Right now .

[0043] Mode 2 is characterized by overall overspeed and stalling / falling (cylinder failure condition). Right now .

[0044] Mode 3 involves excessive velocity dispersion and stalling during a fall (local failure leading to a distorted fall). Right now .

[0045] S4. Fall arrestor triggered. When any of the red emergency trigger conditions are met, the fall arrestor is triggered to lock the braking rail, preventing the climbing frame from continuing to descend.

[0046] S5. Safety Confirmation and Reset. After confirming that the climbing scaffold is in a stable and safe state, release the anti-fall device from locking the braking rail.

[0047] S6. Resume operation.

[0048] Example 2: A wedge-shaped fall arrestor based on the above monitoring method. This example provides a fall arrestor for the above monitoring method and its working principle.

[0049] like Figure 2 , Figure 3 , Figure 4 As shown, the fall arrestor of the present invention is installed between the load-bearing tripod 11 and the braking rail 5, serving as the last safety barrier in reverse travel conditions. The device consists of a disc spring assembly 36, a stress sensor 35, a solenoid valve 32, a wedge brake 31, a reset bolt 33, a reset screw 34, and the braking rail 5.

[0050] like Figure 5As shown, the disc spring assembly 36 is composed of multiple stacked disc springs and is installed inside the wedge-shaped fall arrestor housing 37. One end is fixed to the front end of the wedge-shaped fall arrestor housing 37, and the other end abuts against the rear seat base plate 371. By adjusting the reset bolt 33 at the front end, the disc spring assembly 36 is placed in the designed compression state to store elastic potential energy. The stress sensor 35 is a spoke-type or column-type force sensor, installed between the rear seat base plate 371 and the wedge brake 31. Its installation position must directly bear the entire reaction force of the spring assembly to accurately reflect its real-time stress state. The solenoid valve 32 is a push-pull type DC electromagnet, installed on the side of the wedge-shaped fall arrestor housing 37. Its armature 323 is connected to a high-strength limiting pin 324 at its front end. The pin axis coincides with the axis of the wedge brake slot 312 on the side of the wedge brake 31. The solenoid valve 32 adopts a "power-off locking, power-on release" mode: when power is off, the high-strength limiting pin 324 extends under the action of the return spring 322 and inserts into the wedge brake slot 312, restricting its axial movement; when power is on, the electromagnetic force overcomes the elastic force of the return spring 322 and quickly retracts the high-strength limiting pin 324, releasing the lock. The wedge brake 31 consists of a friction plate 311, a wedge brake slot 312, a limiting and guiding ball 313, and a wedge brake block 314; the wedge brake block 314 is a high-strength steel component, with its rear end in contact with the stress sensor 35, and a wedge brake slot 312 on its side to cooperate with the high-strength limiting pin 324; the front end is equipped with a replaceable friction plate 311, which is made of a high-friction coefficient composite material. The braking rail 5 is a planar friction structure, employing a dedicated braking rail independent of the climbing frame rail, or directly utilizing the climbing frame rail as the braking rail. The surface of the braking rail 5 is hardened, exhibiting high wear resistance, and forms a stable friction pair with the friction plate 311. A limiting and positioning rail 51 is installed within the braking rail 5 for fixing and guiding the wedge-shaped fall arrestor positioning bracket 2. The reset mechanism includes a reset bolt 33 and a reset screw 34. By rotating the reset bolt 33, the disc spring assembly 36 is compressed, thereby pulling the wedge-shaped brake 31 back to its initial position.

[0051] The working principle includes the following steps: S1. During normal descent of the climbing frame, the solenoid valve 32 is de-energized, and the high-strength limiting pin 324 extends under the action of the return spring 322, inserting into the wedge brake slot 312 and locking the wedge brake 31 in its initial position. At this time, the disc spring assembly 36 is in the designed pre-compression state, and the elastic potential energy is constrained by the high-strength limiting pin 324. The stress sensor 35 monitors the spring compression force in real time.

[0052] S2. When the monitoring system issues a red emergency trigger signal, the solenoid valve 32 is instantly energized, and the armature 323 drives the high-strength limit pin 324 to retract quickly, releasing the lock. The disc spring assembly 36 releases its elastic potential energy, pushing the wedge brake 31 forward along the brake track 5. As the wedge brake 31 moves forward, the friction pad 311 quickly presses against the brake track 5. During braking, the stress sensor 35 continuously monitors the thrust of the disc spring assembly. Changes. The system calculates the actual braking force in real time. and the required braking force Comparison: If If insufficient braking force is detected, the system triggers a supplementary alarm and prompts for manual intervention; if Stable at If the displacement sensor indicates that the climbing frame has stopped descending, the braking is considered successful.

[0053] S3. Before resuming the downward climbing operation, pull the wedge brake 31 back using the reset bolt 34 to make the disc spring assembly 36 reach the designed preload force; after the stress sensor confirms that the standard is met, the solenoid valve 32 is de-energized, and the high-strength limit pin 324 is ejected into the wedge brake slot 312. The climbing frame resumes the downward climbing operation.

[0054] To further ensure reliability under extreme operating conditions, this invention adopts the following redundancy and safety design: the key triggering link adopts a dual solenoid valve parallel design, with the pins of the two solenoid valves simultaneously inserted into the two independent slots of the wedge brake; when triggered, the two solenoid valves are energized simultaneously, and the lock can be released if either solenoid valve operates normally.

[0055] Example 3: A hydraulic climbing formwork monitoring system based on three criteria of tilt, acceleration and velocity, comprising: a monitoring platform defined by the above monitoring method; the aforementioned fall protection device; and an Internet of Things communication module connecting the monitoring platform and the fall protection device.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various improvements and modifications without departing from the spirit and principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hydraulic climbing formwork monitoring method based on three criteria: tilt angle, acceleration, and velocity, characterized in that, Includes the following steps: Sensor system deployment and data acquisition steps: Tilt sensors, displacement sensors and acceleration sensors are deployed on the hydraulic climbing formwork, and the data is uploaded to the cloud monitoring platform in real time through the Internet of Things via a data acquisition device. Real-time calculation steps for motion state parameters: Real-time calculation of the overall tilt of the climbing frame and the descent speed of each machine position. Overall downward speed Machine position speed dispersion and downward composite acceleration ; The graded early warning and fall protection triggering steps are as follows: Based on a preset three-level threshold system, single parameter discrimination is performed. When any parameter reaches the early warning threshold, a yellow warning is triggered. When the alarm threshold is reached, an orange alarm is triggered and automatic deceleration is performed. When the multi-parameter fusion triggering conditions are met, it is determined to be a red emergency state, and a triggering command is sent to the fall protection device.

2. The monitoring method according to claim 1, characterized in that, The motion state characteristic parameters are calculated as follows: overall tilt. Machine speed Overall speed v ( t This represents the weighted average speed of each machine position. For the first i Each camera position t Cumulative displacement at time intervals For the first i Each camera position Cumulative displacement at time intervals The sampling frequency; velocity dispersion ; For the first i The instantaneous speed of each camera position, from Find out, The speed is a weighted average of multiple camera positions. n Number of machine positions; Downward composite acceleration , where g is the acceleration due to gravity.

3. The monitoring method according to claim 1, characterized in that, The three-level threshold system is: tilt. Normal <0.3°, 0.5°> Warning: ≥0.3°, 0.8°> Alarm ≥0.5° Trigger angle ≥0.8°; Overall speed Normal <0.8 , > Warning ≥ 0.8 , Warning > Machine position speed dispersion Normal velocity dispersion <0.1m / min, 0.15m / min> Warning ≥0.1m / min, velocity dispersion Alarm speed ≥ 0.15 m / min; Downward composite acceleration Normal >-0.2g, synthetic acceleration Warning ≤ -0.2g, synthetic acceleration Alarm ≤ -0.3g, composite acceleration Trigger ≤ -0.5g and t ≥ 200ms.

4. The monitoring method according to claim 1, characterized in that, The specific conditions for triggering the graded early warning and fall prevention are: yellow warning, orange alarm, and red emergency (trigger level).

5. A wedge-shaped fall arrestor for use in the monitoring method according to any one of claims 1-4, characterized in that, Includes a butterfly spring assembly (36), a stress sensor (35), a solenoid valve (32), a wedge brake (31), a reset mechanism (reset bolt (33) and reset screw (34)) and a brake rail (5); The butterfly spring assembly (36) is installed inside the wedge-shaped fall arrestor housing (37), with one end fixed to the front end of the wedge-shaped fall arrestor housing (37) and the other end fixed to the rear seat base plate (371), and is in a pre-compressed energy storage state; the stress sensor (35) is connected in series with the butterfly spring assembly (36) to sense the compression force value in real time; the solenoid valve (32) adopts the power-off locking and power-on release mode, and its high-strength limiting pin (324) cooperates with the wedge brake slot (312); the front end of the wedge brake (31) is provided with a friction plate (311); the brake rail (5) can be set as a dedicated brake rail independent of the climbing frame rail according to the required braking force, or the climbing frame rail can be directly used as the brake rail; the reset mechanism includes a reset bolt (33) and a reset screw (34), which are used to pull the wedge brake (31) back to the initial position.

6. The wedge-shaped fall arrestor according to claim 5, characterized in that, The tilt angle of the wedge brake (31) a The friction coefficient of friction plate (311) is between 30° and 45°. μ ≥0.4; the preload of the disc spring assembly (36) is designed to be ≥0.

4. Maximum elasticity satisfies ,in For the required braking force, G This represents the total weight of the climbing scaffold. k s For safety factor (take 1.5-2.0).

7. The wedge-shaped fall arrestor according to claim 6, characterized in that, Braking force when braking is triggered The stress sensor monitors the thrust of the disc spring assembly (36) in real time. And calculate the actual braking force ,like The system will then determine that the braking force is insufficient and trigger a supplementary alarm.

8. The wedge-shaped fall arrestor according to claim 5, characterized in that, It also includes the following redundant safety design: a dual solenoid valve parallel design, which can be released by the action of either solenoid valve.

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