Measurement apparatus for braking distance of mine fall arrester, and measurement method therefor

Abstract

A measurement apparatus for the braking distance of a mine fall arrester, the measurement apparatus comprising a housing (1), wherein a display screen (2) is provided on the housing (1); an optical observation window (3), indicator lights (5), functional operation buttons (6), a mode switch (7), a memory card slot (8), and a data transmission interface (9) are provided on the front face of the housing (1); a cubic neodymium magnet (10) is provided on the back face of the housing (1); an optical glass column (11), a laser ranging module (13), a measurement LED fill light module (14), an imaging module (15), and an outwardly-flared metal shielding cover (16) are provided at the lower portion of the housing (1); and a central control module (17), a GPS module (18), an active ceramic GPS antenna (19), a wireless receiver module (20), a wireless transmitter module (21), a 315MHz control module (22), a 433MHz communication output module (23), a nine-axis accelerometer and gyroscope module (24), a power supply module, and a loudspeaker module (26) are provided in the housing (1). Further provided is a measurement method for the braking distance of a mine fall arrester.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a measurement apparatus for a braking distance of a mining cage fall arrester, and a measurement method based on the apparatus, and belongs to the field of inspection and testing. BACKGROUND

[0002] According to the requirements in the energy industry standard NB / T 10050-2018 "Inspecting-Testing Specification of Parachute In-Service for Vertical Shaft Hoisting System of Coal Mines" and other relevant standards, the regular testing of various mining cage fall arresters is an important means to ensure the safe production. The testing items for mining cage fall arresters of hoisting systems in vertical shafts include a non-detachment test, a no-load detachment test, a heavy-load detachment test, etc. There have been relatively perfect solutions for the non-detachment test. The detachment tests are still faced with various drawbacks.

[0003] The detachment tests are mainly intended to measure a descending distance of a mining cage fall arrester. In order to reflect the actual braking performance of a mining cage fall arrester intuitively, it is necessary to detect a distance of a cage to pass at each stage after detaching, including a distance before braking, a distance during braking, etc. In order to meet the standard needs, sometimes a braking distance is combined with a time to analyze other parameters such as braking deceleration and idle travel time.

[0004] Under the existing conditions, both the no-load detachment test and the heavy-load detachment test for the braking of mining cage fall arresters can lead to a huge impact. The traditional cage fall arrester measuring instrument needs to be connected to a cage or a mining cage fall arrester for testing. There will be a very strong impact force at the moment of braking. The huge impact and vibration affect the degree of linearity and the physical structure of the traditional mining cage fall arrester measuring instrument, and are easy to cause the accuracy drift and the damage to a structure of the instrument. With the CCZ-series mining cage fall arrester measuring instrument as an example, this instrument adopts a linear potentionmeter for measuring based on the rigid connection. The concentricity and sliding contact points of the linear potentionmeter are easily damaged under a huge impact, which affects the accuracy and leads to the uncontrollable data drift. Currently, the traditional technologies and the conventional means cannot solve these problems well and thoroughly. Other single measurement methods also have various drawbacks. There are currently no targeted designs and schemes on the market to solve the drawbacks. SUMMARY

[0005] The present disclosure provides a measurement apparatus for a braking distance of a mining cage fall arrester, and a measurement method based on the apparatus, so as to solve the problems such as accuracy drift and easy damage to instrument structures in the existing measurement forbraking distances of mining cage fall arresters.

[0006] In order to achieve the above objective, the present disclosure provides a measurement apparatus for a braking distance of a mining cage fall arrester, and belongs to the field of inspection and testing. The measurement apparatus for a braking distance of a mining cage fall arrester in the present disclosure includes a housing. A front side of the housing is provided with an optical observation window, and the optical observation window runs through the entire housing. The housing is provided with an inclined reflecting mirror at a position of a hole behind the optical observation window.

[0007] The front side of the housing is further provided with a display screen, a plurality of indicator lights, functional operation buttons, a mode switch, a memory card socket, and a data transmission interface.

[0008] A cubic neodymium magnet is provided at a back side of the housing and below the reflecting mirror. A surface of the neodymium magnet is plated with gold. Five sides of the neodymium magnet each are wrapped with mm polytetrafluoroethylene, and the polytetrafluoroethylene is wrapped with a metal shielding layer externally. The neodymium magnet is connected to a core of a feeder, and the metal shielding layer is connected to a shielding layer of the feeder. The neodymium magnet protrudes from the back side of the housing.

[0009] A bottom of the housing is provided with a concave region that is closed with a transparent optical sapphire cover plate. An optical glass column, a laser ranging module, a measuring light-emitting diode (LED) fill light module, a camera module, and a trapezoidal metal shielding enclosure flared outwards are provided at an inner side of the cover plate. A peripheral side of the optical glass column is frosted, and two ends of the optical glass column are glossy. One glossy end of the optical glass column is bonded to the transparent optical sapphire cover plate, and the other glossy end of the optical glass column is bonded to a laser-emitting head of the laser ranging module.

[0010] A central control module, a Global Positioning System (GPS) module, an active ceramic GPS antenna, a wireless receiving module, a wireless transmitting module, an M control module, an M communication output module, a 9-axis accelerometer and gyroscope module, and a speaker module are provided inside the housing. The central control module includes an input signal bus and an output signal bus. The GPS module, the laser ranging module, the wireless receiving module, the camera module, the 9-axis accelerometer and gyroscope module, the M control module, and the functional operation buttons each are connected to the input signal bus. The display screen, the wireless transmitting module, the plurality of indicator lights, the M communication output module, the speaker module, the measuring LED fill light module, and an observing LED fill light module each are connected to the output signal bus.

[0011] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, left and right sides of the housing each are provided with a breaking-proof rubber edge trim that is made of a polyurethane (PU) material and protrudes from a surface of a body of the apparatus. Each breaking-proof rubber edge trim is provided with a removal groove at both upper and lower positions. A middle of each breaking-proof rubber edge trim is provided with a strap-fixing region that is recessed towards a center of the body of the apparatus and is configured to embed and fix a strap.

[0012] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, the plurality of indicator lights are arranged above the optical observation window, and are as follows from left to right sequentially: a yellow indicator light, a green indicator light, a blue indicator light, and a red indicator light. The yellow indicator light indicates preheating, the green indicator light indicates working, the blue indicator light indicates an ending, and the red indicator light indicates a fault. When the red indicator light is on, all programs and detection actions are terminated until the apparatus is manually restarted.

[0013] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, a middle of the back side of the housing is provided with a trapezoidal prism. The neodymium magnet is arranged in a recessed region of the trapezoidal prism, and the neodymium magnet protrudes from the back side of the housing by mm. The apparatus further includes the observing LED fill light module that is arranged in a strip-like protruded region below the neodymium magnet and irradiates the neodymium magnet above. The observing LED fill light module is connected to the output signal bus.

[0014] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, a top of the housing is provided with a recessed region, and a power switch, a charging interface, and a SubMiniature version A (SMA) interface are provided from left to right sequentially in the recessed region. The mode switch is connected to a power amplifier, and the power amplifier is connected to the wireless transmitting module.

[0015] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, there are three metal shielding enclosures that are nested, parallel to each other, insulated from each other, and mm spaced from each other. An innermost metal shielding enclosure is connected to the shielding layer of the feeder of the wireless receiving module. The innermost metal shielding enclosure includes a chip directional antenna. The innermost metal shielding enclosure is insulated from the chip directional antenna, and the chip directional antenna is connected to the wireless receiving module through the core of the feeder. A built-in wireless radio frequency power detection module is provided in the wireless receiving module.

[0016] According to the measurement apparatus for a braking distance of a mining cage fall arrester described above, the 9-axis accelerometer and gyroscope module integrates a 3-axis accelerometer, a 3-axis magnetometer, and a 3-axis gyroscope. The 9-axis accelerometer and gyroscope module has a static attitude measurement accuracy not exceeding 0.05° and a dynamic attitude measurement accuracy not exceeding 0.1°, includes a built-in Kalman attitude determination algorithm, and has a magnetometer ellipsoid correction function, △acceleration represents an acceleration fluctuation variable, A3-axis gyroscope data represents an X, Y, and Z axis fluctuation variable, and Aellipsoid magnetic data represents a magnetometer data fluctuation variable after an ellipsoid fitting algorithm.

[0017] The present disclosure also provides a measurement method based on the measurement apparatus for a braking distance of a mining cage fall arrester described above,

[0018] including the following steps:

[0019] 1) arranging the apparatus at a measuring position as required, checking an adsorption state through the optical observation window, and selecting a corresponding measuring mode;

[0020] 2) starting a power supply such that the yellow indicator light of the apparatus is on; performing a cold start for the GPS module while broadcasting a prompt voice including a required distance between personnel and the apparatus; after the broadcasting of the prompt voice is completed, powering the 9-axis accelerometer and gyroscope module on to enter a working state; acquiring acceleration data, 3-axis gyroscope data, and magnetometer data after the ellipsoid fitting algorithm in real time, and recording GPS data acquired by the GPS module; and calibrating a time of the apparatus according to a time acquired by the GPS module;

[0021] 3) calculating Aacceleration, A3-axis gyroscope data, and Aellipsoid magnetic data; when Aacceleration and A3-axis gyroscope data are less than 0.1% and Aellipsoid magnetic data is less than 1% within 5 s, directly entering the next step; when the Aacceleration and the A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, repeating the calculating with a 5 s delay, and iterating for no more than 5 times; when there are more than 5 times of the iterating or Aacceleration and A3-axis gyroscope data in a single time are greater than 0.3% and less than 0.6%, prompting to check an environmental vibration factor, and making the red indicator light on;

[0022] 4) executing a single-threaded monitoring task, directly entering the next step, and terminating the single-threaded monitoring task when a movement of a cage is detected, where the single-threaded monitoring task has a delayed error-reporting function; and if a movement of the cage is detected, delayed error reporting is terminated, a subsequent error-reporting action is no longer executed, and the single-threaded monitoring task is terminated;

[0023] 5) powering the wireless transmitting module, the power amplifier, and the wireless receiving module on; detecting and setting an optimal channel, performing statistical analysis on signal intensities of effective coding signals, and counting and calculating an average value, a standard deviation, and a range for signal intensities dbm received within 5 s; when a ratio of the standard deviation to the average value for the signal intensities dbm does not exceed 0.5%, that is, the standard deviation / average value is less than or equal to 0.5%, and a ratio of the range to the average value for the signal intensities dbm does not exceed 5%, that is, the range / average value is less than or equal to 5%, directly entering the next step, otherwise prompting to report an error by the display screen, including two types of errors; if the range / average value is more than or equal to 10%, reporting an error prompting that a signal receiving and transmitting module is suspected to be faulty; and for situations other than the above situation, collectively reporting an error prompting that there is a radio interference to be eliminated on site, and making the red indicator light on;

[0024] 6) setting a sampling rate of a camera to a rated operating frame rate, and loading data captured by the camera into a random access memory (RAM) of a central controller; denoising information of a top of the cage that is captured by the camera, smoothing an image with a Gaussian filter, and calculating a gradient intensity and direction of each pixel in the image with a Sobel operator; conducting a maximum detection in the gradient direction; only retaining pixels with a maximum gradient; dividing the pixels into strong edges, weak edges, and non-edges; directly outputting the strong edges, directly discarding the non-edges, and outputting the weak edges only when the weak edges are connected to the strong edges; connecting the weak edges to the strong edges with a connectivity analysis algorithm to produce complete edges, and dividing the complete edges into single line segments along an intersection point; selecting and marking line segments for an edge of the cage that meet requirements by a tester with a 315M wireless controller; after the selection is determined by the tester, recording length and coordinate position information of the current line segments for the edge of the cage in image data, measuring a distance from the apparatus to the top of the cage by the laser ranging module, recording the distance as DI, and making the green indicator light on to indicate that the apparatus is ready; prompting by the display screen (2) that a detachment test is able to be conducted; continuing the sampling by the camera at the rated operating frame rate, and writing sampled video data into the RAM in real time with a low resource consumption strategy; and retaining only the first 1,000 ms high-speed video data in the RAM, and overwritting high-speed video data circularly, where video information in the RAM exists in a form of raw data and does not undergo additional analysis and coding by a central processing unit (CPU);

[0025] 7) executing a program in a default mode if there are no settings, or executing the program in a strict mode according to settings of a user if any; and in both modes, directly entering the next step after a corresponding program is normally terminated, where the program in the default mode is characterized in that: when a change of a current coding signal intensity is ±20% greater than an average coding signal intensity and fails to be restored to the average coding signal intensity, a time when an instantaneous change occurs is taken as Tl, and regardless of whether the coding signal intensity is restored, the laser ranging module is linked for ranging at the time Tl when the coding signal intensity dbm changes instantaneously, and a ranging result is recorded as DC; if the coding signal intensity is not restored after 500 ms, the program execution is terminated normally; and if the change of the coding signal intensity dbm is more than ±20% of the average coding signal intensity, but is able to be restored to 5% or less of the average coding signal intensity within 500 ms, a user is prompted that the signal receiving and transmitting module is faulty probably, error reporting is executed, Tl and DC variables are cleared, and the red indicator light is on;

[0026] 8) stopping the low resource consumption strategy of the camera and the video data overwritting strategy of the RAM, such that sampled video data recorded in real time in the RAM is not overwritten; increasing a clock speed of the CPU to a maximum clock speed, stopping an output of the display screen, and releasing memory resources occupied by displaying of the display screen; analyzing and processing video data in real time, and adding a marker to a video frame at the time Tl; detecting a motion state of a "cage edge" with an optical flow algorithm; when the "cage edge" stops changing, recording a current time as T2; adding a marker to a video frame at the time T2, linking the laser ranging module for ranging, and recording a ranging result as D2; and stopping capturing of the camera and writing of a video into the RAM, compressing and storing a sampled video in a H.265 format in a read-only memory (ROM), and embedding GPS metadata acquired by the GPS module into a video file;

[0027] 9) calculating D2 - DI = D3; analyzing a video stream frame by frame; finding cage edges according to length and coordinate position information for line segments of marked cage edges; tracking and identifying a cage edge in each frame with a mean-shift algorithm; and tracking and recording a pixel position change of the cage edge in each frame, and calculating an actual displacement:

[0028] (a) calculating a pixel position difference APi between cage edges at a frame i and a frame i+1,

[0029] (b) summing all APi values to produce a total pixel displacement APt,

[0030] (c) dividing D3 by the total pixel displacement APt to produce a conversion ratio K, that is, K = D3 / APt, and

[0031] (d) calculating AD = K * APi and AT = 1 / an operating frame rate of the camera;

[0032] 10) curve plotting: setting a time T as an x-coordinate, a displacement distance D as a y-coordinate, and a starting point of a curve as an origin (Tl, DI) for coordinate axes, where a T1 point represents a time point when the cage is not displaced at the moment of detaching and a DI point represents a measured value of the laser ranging module when the cage does not move; determining each point in a coordinate system according to a calculated actual displacement distance value AD of each cage edge and a time interval AT between two frames, and connecting resulting points successively to plot a curve A of a change of a distance over time, where D2 is an end point of the curve; D3 represents a difference between D2 and DI, that is, an actual displacement of the cage before and after an action of a mining cage fall arrester; and T2 represents a stop point of a movement of the cage; and plotting an expected curve according to a law of v = gt, that is, D = 0.5 gtA2, where a separation point of the two curves is (Tx, Dx); a D value of an overlapped part of the two curves is an idle travel distance, that is, DI to Dx is an idle travel distance; a T value of the overlapped part of the two curves is an idle motion time, that is, Tl to Tx is an idle travel time; and Dx to D2 is a deceleration distance, and Tx to T2 is a deceleration time; and

[0033] 11) restoring the output of the display screen, outputting and displaying the curves in a picture format, and storing the curves in the same folder as a current video, where the folder is named after a location and time recorded by the GPS; and outputting a difference between DC and DI or a difference between DC2 and DI, prompting personnel to check the difference, and making the blue indicator light on.

[0034] 9. In the measurement method based on the measurement apparatus for a braking distance of a mining cage fall arrester according to claim 8, in the step 4), when the △acceleration and A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, counting is conducted once; if the counting is conducted 5 times or the Aacceleration and △3-axis gyroscope data in a single time are greater than 0.3%, an error-reporting delay is started, and with a 1,500 ms delay, an error is reported, a prompt that there is a too-large vibration to be eliminated and whether the apparatus is fixed at a rigid connection needs to be manually confirmed is given, and the red indicator light is on.

[0035] 10. In the measurement method based on the measurement apparatus for a braking distance of a mining cage fall arrester according to claim 8, the step 7) further includes the following steps:

[0036] 1) preprocessing signals, and selecting the strongest signal in a selected working channel as a valid signal to be selected;

[0037] 2) verifying a check bit for the valid signal to be selected, and after the verification is successful, recording the valid signal to be selected as a valid signal, and calculating a proportion of invalid signals in total signals in real time;

[0038] 3) if the proportion of invalid signals is greater than 0.1%, directly reporting an error to prompt a user that there is a poor radio environment on site and signal interference needs to be eliminated or a default mode is selected for detection, and after the error reporting, terminating the step and making the red indicator light on;

[0039] 4) if there is no error reporting, further verifying the valid signal, and checking whether a code number of a file header for the valid signal is consecutively related to a code number for the previous signal; if consecutive, then conducting effective counting, and when the effective counting is conducted 10,000 times, jumping to execute the next step to calculate and count time information of a coding signal; if not consecutive, interrupting the counting; and if a number of times to interrupt the counting accumulates to 10, reporting an error to prompt that there is an interference for a channel or poor adsorption of the magnet to be eliminated, and making the red indicator light on; and

[0040] 5) calculating a difference between time information carried by a valid coding signal received each time and a current system time in the valid signal, which is referred to as "difference" in the follow-up description; taking an average value of 10,000 differences, which is referred to as an "average" in the follow-up description; comparing a difference received each time with the average; when difference changes in three times are more than ±10% of the average, taking a time when an instantaneous change of time information is first detected as Tl, and regardless of whether a difference continues to change, linking the laser ranging module for ranging at the time Tl when a change of time information carried by the valid coding signal is first detected, and recording a ranging result as DC2; if a difference change still exceeds ±10% of the average subsequently, normally terminating the program execution; if a difference change is restored to ±10% or less of the average, continuing the time average comparison strategy, clearing T1 and DC2 variables, and making the green indicator light flashed to prompt that there is poor contact adsorption of the magnet probably.

[0041] Advantages of the present disclosure: A distance change trend of the whole breaking process of a mining cage fall arrester is measured by the combined methods that can support each other, and detection data is analyzed by a scientific analysis method, which overcomes the defects and shortcomings of the traditional measuring scheme.

[0042] The measuring apparatus allows scientific measuring, and solves the shortcomings of single measurement modes of the existing measuring apparatuses. All aspects of the measuring apparatus support each other to comprehensively improve the overall function of the measuring apparatus. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] FIG. lisa stereoscopic view of a front of the present disclosure;

[0044] FIG. 2 is a stereoscopic view of a rear of the present disclosure;

[0045] FIG. 3 is a stereoscopic view of a top of the present disclosure;

[0046] FIG. 4 is a stereoscopic view of a bottom of the present disclosure;

[0047] FIG. 5 shows a circuit connection relationship of the present disclosure; and

[0048] FIG. 6 is a schematic diagram of braking distance curves plotted by the braking test method of the present disclosure.

[0049] Reference numerals: 1. housing, 2. display screen, 3. optical observation window, 4. reflecting mirror, 5. indicator light, 6. functional operation button, 7. mode switch, 8. memory card socket, 9. data transmission interface, 10. neodymium magnet, 11. optical glass column, 12. transparent optical sapphire cover plate, 13. laser ranging module, 14. measuring LED fill light module, 15. camera module, 16. metal shielding enclosure, 17. central control module, 18. GPS module, 19. active ceramic GPS antenna, 20. wireless receiving module, 201. wireless power detection module, 21. wireless transmitting module, 22. 315M control module, 23. 433M communication output module, 24. 9-axis accelerometer and gyroscope module, 25. power amplifier, 26. speaker module, 27. trapezoidal prism, 28. observing LED fill light module, 29. power switch, 30. charging interface, 31. SMA interface, 32. breaking-proof rubber edge trim, 33. removal groove, 34. strap-fixing region, 35. directional antenna, 36. output control bus, 37. input control bus, 38. functional A region, 39. functional B region, and 40. functional C region. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] The content of the present disclosure is further described below:

[0051] The measuring apparatus has a housing that is a flat cube overall, and a control circuit is provided inside the housing.

[0052] Specifically, a middle of a front side of the housing is provided with a display screen, and an optical observation window is provided above the display screen. The optical observation window runs through front and back sides of the housing. A speaker opening is formed in a channel of the optical observation window, and the speaker opening cannot be directly seen from the outside, which allows the beautiful appearance.

[0053] The front side of the housing is provided with working-state indicator lights above the optical observation window, including the following from left to right: a yellow indicator light, a green indicator light, a blue indicator light, and a red indicator light. The yellow indicator light indicates preheating, the green indicator light indicates working, the blue indicator light indicates an ending, and the red indicator light indicates a fault. With the indicator lights, a working state of the apparatus can be clearly and directly determined.

[0054] A rectangular functional A region is provided below the display screen in a concave manner. Functional operation buttons are provided at a left part in a space of the functional A region, and a mode switch is provided at an upper right part in the space of the functional A region. Feeders of an SMA interface and a neodymium magnet each are connected to the mode switch. A TransFlash (TF) memory card slot is provided on the left and a TYPE-C data transmission interface is provided on the right below the mode switch.

[0055] A reflecting mirror inclined downwards is provided behind the optical observation window, that is, at a rear side of the housing. The reflecting mirror can be seen in the front of the optical observation window. The reflecting mirror is configured to observe an adsorption and fixation state at the rear side of the housing.

[0056] A cubic neodymium magnet is provided at a trapezoidal prism in a middle of a back side of the housing. Through the reflecting mirror, an adsorption state of the neodymium magnet on a device to be tested can be observed. A surface of the cubic neodymium magnet is plated with gold, and a thickness of a gold plating layer is greater than 50 pm. Five sides of the cubic neodymium magnet each are wrapped with 1 mm polytetrafluoroethylene, and the polytetrafluoroethylene is wrapped with a trapezoidal metal shielding layer externally. The neodymium magnet is connected to a core of a feeder, and the metal shielding layer is connected to a shielding layer of the feeder. The neodymium magnet protrudes from a body of the apparatus by 0.5 mm. The plating on an outer surface of the neodymium magnet can be embossed, and useless words are removed, so as to prevent the apparatus from being damaged by workers due to picking when lost. The feeder is connected to a power amplification module of the internal control circuit.

[0057] A strip-like protruded region is provided below the neodymium magnet, and is configured to arrange a strip-like observing LED fill light module for the optical observation window to observe an adsorption state of the magnet. The observing LED fill light module irradiates the neodymium magnet. The reflecting mirror allows the observation of an adsorption state of the neodymium magnet through the optical observation window.

[0058] Left and right sides of the housing each are provided with a breaking-proof rubber edge trim that is made of a PU material and protrudes from a surface of a body of the apparatus. Each breaking-proof rubber edge trim is provided with a removal groove at both upper and lower positions. At the end of a detection, when the housing is recovered, the entire housing magnetically adsorbed is removed by fingers. A middle of each breaking-proof rubber edge trim is provided with a strap-fixing region that is recessed towards a center of the body of the apparatus, such that a strap can be bundled and fixed around a perimeter of the housing, which facilitates the fixation of devices with different structures to be tested.

[0059] A top of the housing is provided with a rectangular functional B region in a concave manner. Specifically, a power switch, a charging interface, and an SMA interface are provided from left to right sequentially in the rectangular functional B region.

[0060] A bottom of the housing is provided with a concave functional C region, and an artificial transparent optical sapphire square cover plate is provided at an opening. The cover plate seals the functional C region at the opening, and a thickness of the cover plate is 2 mm. A periphery of an optical glass column is frosted, and two ends of the optical glass column are glossy. One glossy end of the optical glass column is bonded to an inner side of the cover plate, and the other glossy end of the optical glass column is bonded to a laser-emitting head of the laser ranging module. An adhesive is preferably a 705 optical silicone rubber, and the use of a ultraviolet (UV)-curing adhesive for bonding is banned. A black light-absorbing coating covering surface is also provided in the functional C region overall. One end of the functional C region is provided with a measuring LED fill light module, and the other end of the functional C region is provided with a camera module. A barrel distortion rate of the camera module should be less than 0.1%. The camera module adopts a fixed focus. An angle of view for the camera module should be greater than or equal to 69.9° and should not be more than 90°. An optimal focal length of the camera module is 4 mm (after the lens). A sampling rate of the camera module is greater than or equal to 1,000 fps / s. A lens of the camera module is preferably a coated optical glass lens.

[0061] Three trapezoidal metal shielding enclosures that are flared outwards, nested, parallel to each other, insulated from each other, and 1 mm spaced from each other are provided at a center of the functional C region. An innermost metal shielding enclosure is connected to the shielding layer of the feeder of the wireless receiving module. The innermost metal shielding enclosure includes a chip directional antenna, and is insulated from the chip directional antenna. The chip directional antenna is connected to the wireless receiving module through the core of the feeder. A built-in wireless radio frequency power detection module is provided in the wireless receiving module.

[0062] A central control module, a GPS module, an active ceramic GPS antenna, a wireless receiving module, a wireless transmitting module, a 315M control module, a 433M communication output module, a 9-axis accelerometer and gyroscope module, a power-supply module, and a speaker module are provided inside the housing.

[0063] The central control module includes an input signal bus and an output signal bus. A core of the central control module adopts a high-performance 64-bit quad-core processor, an LPDDR4 memory, and standard 40-pin GPIO interfaces, including power-supply and programmable GPIOs and some GPIOs that can be multiplexed as IIC, SPI, UART, PWM, etc.

[0064] The GPS module 18, the laser ranging module 13, the wireless receiving module 20, the camera module 15, the 9-axis accelerometer and gyroscope module 24, the 315M control module 22, and the functional operation buttons 6 each are connected to the input signal bus. The display screen 2, the wireless transmitting module, the plurality of indicator lights 5, the 433M communication output module 23, the speaker module 26, and the measuring LED fill light module 28 each are connected to the output signal bus. Feeders of the SMA interface 31 and the neodymium magnet 10 each are connected to the mode switch 7. The mode switch 7 is connected to a power amplifier, and the power amplifier is connected to the wireless transmitting module 21.

[0065] Specific specification requirements for the components are as follows: The GPS module is a multi-mode satellite navigation and positioning module, which supports the single-system positioning and multi-system joint positioning of the BDS / GPS / GLONASS satellite navigation system and also supports the QZSS and SBAS systems. The active ceramic GPS antenna is connected to the GPS module.

[0066] The receiving and transmitting frequency bands of the wireless receiving module and the wireless transmitting module are matched, and the transmitting and receiving frequencies are not less than 2 GHz and not more than 6 GHz. The wireless receiving module support the six-channel data reception and modulation modes such as GFSK / FSK, has a frequency of no less than 126 to meet the needs of multi-point communication and frequency-hopping communication and a sensitivity of at least -96 dbm (when a rate in the air is 250 kbps), and is integrated with high-PSRR LDO inside.

[0067] The 9-axis accelerometer and gyroscope module integrates a 3-axis accelerometer, a 3-axis magnetometer, and a 3-axis gyroscope. The 9-axis accelerometer and gyroscope module has a static attitude measurement accuracy not exceeding 0.05° and a dynamic attitude measurement accuracy not exceeding 0.1°, includes a built-in Kalman attitude determination algorithm, has a magnetometer ellipsoid correction function, and supports the two transmission modes of serial output and IIC output.

[0068] The 315M control module is configured for a worker to control the apparatus through a wireless operation to select an edge of a cage, and most of the 315M control modules on the market can meet the needs. The 433M communication output module is configured to output data such as printing data, with a transmission rate of no less than 19.2 kbps.

[0069] The power-supply module of the present disclosure adopts a lithium-ion battery for power supplying, and includes a charge / discharge integrated protective plate. The power-supply module provides electric energy for the internal electrical components.

[0070] Description of a coding signal of the wireless transmitting module: The coding signal is divided into the following three units: file header + time information + CRC check code. The file header includes a code number. A separate transmission time slot for the code is adjustable, but a maximum time slot shall not be greater than one-tenth of a single frame time when the camera is working. If an operating frame rate of the camera is 10,000 frames / s, the separate transmission time slot for the code should not exceed 10 ps.

[0071] A measurement method using the apparatus is described in detail below:

[0072] SI: Preparation: The neodymium magnet plated with gold on a back side is adsorbed to a rigid metal connection frame of a detacher or a fixed detacher, and cannot be adsorbed to a movable component. A fixing strap on a side of the housing is embedded and fixed in the strap-fixing region. The fixing strap is fixed to the rigid metal connection frame of the detacher or the fixed detacher, which should ensure that the measuring apparatus does not move and shake when working. If an on-site situation cannot meet this requirement, a special bracket for fixing the measuring apparatus can be additionally provided. After the fixation is completed, an adsorption and fitting state of the magnet should be checked through the optical observation window. If there is a light leakage at an adsorption and fitting site, it indicates that the adsorption and fitting is incomplete, and the measuring apparatus needs to be adjusted to a smooth plane meeting requirements for arranging.

[0073] An angle of the measuring apparatus is adjusted, such that the camera faces a top of a cage. Four sides of the top of the cage should be seen on the screen. If an arrangement angle does not meet the requirements, the measuring apparatus should be removed and adjusted, and should not be rotated directly when the measuring apparatus is adsorbed.

[0074] S2: A power supply is started such that the yellow indicator light is on. The voice "please wait when the apparatus is ready to start calibration, do not move or touch the apparatus, and stay 1 m or more away from the cage" is broadcasted, and the cold start is performed in the GPS module. The camera is started, and real-time video information captured by the camera is displayed on the screen. At this point, a sampling rate of the camera is a screen refresh rate.

[0075] After the broadcasting of the voice is completed, the 9-axis accelerometer and gyroscope module is powered on to enter a working state. Acceleration data, 3-axis gyroscope data, and magnetometer data after a ellipsoid fitting algorithm are acquired in real time, and GPS data acquired by the GPS module is recorded. A time of the apparatus is calibrated according to a time acquired by the GPS module.

[0076] S3: In this step, S3.1 is executed first, and it is possible to jump from S3.1 to S3.2.

[0077] S3.1 Aacceleration (acceleration fluctuation variable), A3-axis gyroscope data (X, Y, and Z axis fluctuation variable), and Aellipsoid magnetic data (magnetometer data fluctuation variable after an ellipsoid fitting algorithm) are calculated. When Aacceleration and A3-axis gyroscope data are less than 0.1% and Aellipsoid magnetic data is less than 1% within 5 s, it directly jumps to S3.2. When the Aacceleration and the A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, the detection and calculation in this step is repeated with a 5 s delay, and 5 times of the iterating are allowed at most. When there are more than 5 times of the iterating or Aacceleration and A3-axis gyroscope data in a single time are greater than 0.3% and less than 0.6%, the program is terminated while the prompt voice "there is a too-large environmental vibration factor, the nearby devices such as a traction machine and a water pump should be suspended by a worker on site until the end of a detachment test, and the apparatus requires a calibration and testing time of about 2 min" is broadcasted, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI.

[0078] S3.2 A single-threaded program task is executed, and it directly jumps to S4. The single-threaded program task is a monitoring task, and the monitoring task is terminated when a program in S6 is executed. In this single-threaded task, if it is detected that the program in the S6 is executed, delayed error reporting is terminated, a subsequent action is no longer executed, and the single-threaded task is terminated. Actions for executing the program are as follows: When the Aacceleration and A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, counting is conducted once. If the counting is conducted 5 times or the Aacceleration and A3-axis gyroscope data in a single time are greater than 0.3%, an error-reporting delay is started. With a 1,500 ms delay, the following action is executed: the program is terminated while the prompt voice "there is a too-large vibration, please eliminate this problem, and double-check whether the housing is fixed to a rigid connection" is broadcasted, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI.

[0079] S4: The wireless transmitting module, the power amplifier, and the wireless receiving module are powered on. A state of each channel is detected, and an optimal channel is set. Statistical analysis is performed on signal intensities of effective coding signals, and an average value, a standard deviation, and a range for signal intensities dbm received within 5 s are counted and calculated. When a ratio of the standard deviation to the average value does not exceed 0.5%, that is, the standard deviation / average value is less than or equal to 0.5%, and a ratio of the range to the average value does not exceed 5%, that is, the range / average value is less than or equal to 5%, it directly jumps to S5, otherwise an error is reported.

[0080] There are two types of errors there. If it is detected that the range / average value is more than or equal to 10%, the following error is reported: a signal receiving and transmitting module is suspected to be faulty. If the error occurs many times, the apparatus should be returned to the factory for maintenance. For situations other than the above situation, the following error is collectively reported: there is a radio interference to be eliminated on site. The program is terminated while an error is reported, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI.

[0081] S5: A sampling rate of a camera is set to a rated operating frame rate, and data captured by the camera is loaded into RAM. Information of a top of the cage is denoised, an image is smoothed with a Gaussian filter, and a gradient intensity and direction of each pixel in the image are calculated with a Sobel operator. A maximum detection is conducted in the gradient direction. Only pixels with a maximum gradient are retained. The pixels are divided into strong edges, weak edges, and non-edges. The strong edges are directly output, the non-edges are directly discarded, and the weak edges are output only when the weak edges are connected to the strong edges. The weak edges are connected to the strong edges with a connectivity analysis algorithm to produce complete edges, and the complete edges are divided into single line segments along an intersection point. Line segments for the edge of the cage that meet requirements are selected and marked by a tester with a 315M wireless controller. After the selection is determined by the tester, length and coordinate position information of the current line segments for the edge of the cage is recorded, a distance from the measuring apparatus to the top of the cage is measured by the laser ranging module once and recorded as DI, and the green indicator light is on to indicate that the apparatus is ready and a detachment test can be conducted. An operator is guided to release the cage to complete a mining cage fall arrester test.

[0082] The sampling is continued by the camera at the rated operating frame rate, and sampled video data is written into the RAM in real time with a low resource consumption strategy. Only the first 1,000 ms high-speed video data is retained in the RAM, and high-speed video data is overwritten circularly. Video information in the RAM exists in a form of raw data and does not undergo additional analysis and coding by CPU.

[0083] S6: According to settings of a user, S6.1 or S6.2 is executed, and S6.1 is executed by default.

[0084] S6.1 Default mode: When a change of a current coding signal intensity is ±20% greater than an average coding signal intensity and fails to be restored to the average coding signal intensity calculated in the S4, a time when an instantaneous change occurs is taken as Tl, and regardless of whether the coding signal intensity is restored, the laser ranging module is linked for ranging at the time Tl when the coding signal intensity dbm changes instantaneously, and a ranging result is recorded as DC. If the coding signal intensity is not restored after 500 ms, the program execution is terminated normally, and the S7 is executed. If the change of the coding signal intensity dbm is more than ±20% of the average coding signal intensity, but can be restored to 5% or less of the average coding signal intensity recorded in the S4 within 500 ms, it is prompted that the signal receiving and transmitting module is suspected to be faulty. If the error occurs multiple times, the apparatus should be returned to the factory for maintenance. Moreover, the program is terminated, Tl and DC variables are cleared, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI.

[0085] S6.2 Strict mode:

[0086] Preprocessing: The strongest signal in a selected working channel is selected as a valid signal to be selected. A check bit is verified for the valid signal to be selected, and after the verification is successful, the valid signal to be selected is recorded as a valid signal.

[0087] Each number of valid signals is accumulated to a valid variable, and each number of invalid signals is accumulated to an invalid variable. A proportion of invalid signals in total signals is calculated in real time. If the proportion of invalid signals is greater than 0.1%, an error is directly reported to prompt on the display screen that there is a poor radio environment on site and signal interference needs to be eliminated or a default mode is selected for detection. In addition, the program is terminated, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI.

[0088] The valid signal is further verified, and whether a code number of a file header for the valid signal is consecutively related to a code number for the previous signal is checked. If consecutive, then effective counting is conducted, and when the effective counting is conducted 10,000 times, the next action is continued to calculate and count time information of a coding signal. If not consecutive, the counting is interrupted. If a number of times to interrupt the counting accumulates to 10, the following error is reported on the display screen: there is an interference for a channel or poor adsorption of the neodymium magnet to be eliminated. In addition, the program is terminated, the red indicator light is on, and a start button signal is waited to guide a tester to re-start from the SI. If a number of times to interrupt the counting does not reach 10, the effective counting is re-started.

[0089] A difference between time information carried by a valid coding signal received each time and a current system time is calculated in the valid signal, which is referred to as "difference" in the follow-up description. An average value of 10,000 differences is taken, which is referred to as an "average" in the follow-up description. A difference received each time is compared with the average. When difference changes in three times are more than ±10% of the average, a time when an instantaneous change of time information is first detected is taken as Tl, and regardless of whether a difference continues to change, the laser ranging module is linked for ranging at the time Tl when a change of time information carried by the valid coding signal is first detected, and a ranging result is recorded as DC2. If a difference change still exceeds ±10% of the average subsequently, the program execution is normally terminated, and S7 is executed. If a difference change is restored to ±10% or less of the average, the time average comparison strategy is continued, Tl and DC2 variables are cleared, and the green indicator light is flashed to prompt that there may be poor contact adsorption of the magnet.

[0090] S7: The low resource consumption strategy of the camera and the video data overwritting strategy of the RAM are stopped, such that sampled video data recorded in real time in the RAM is not overwritten. A clock speed of the CPU is increased to a maximum clock speed, an output of the display screen is stopped, and memory resources occupied by displaying of the display screen are released. Video data is analyzed and processed in real time, and a marker is added to a video frame at the time Tl. A motion state of a "cage edge" is detected with an optical flow algorithm. A sampled video is compressed and stored in a H.265 format in ROM, and GPS metadata acquired by the GPS module is embedded into a video file.

[0091] When the "cage edge" stops changing, a current time is recorded as T2. A marker is added to a video frame at the time T2, the laser ranging module is linked for ranging, and a ranging result is recorded as D2. Moreover, the capturing of the camera and the writing in RAM are terminated.

[0092] S8: D2 - DI = D3 is calculated. A video stream is analyzed frame by frame. Edges are found according to initial length and coordinate position information for line segments of marked cage edges. The coordinate position information is acquired in the S5. An edge in each frame is tracked and identified with a mean-shift algorithm. A pixel position change of the edge in each frame is tracked and recorded, and an actual displacement is calculated:

[0093] (a) A pixel position difference APi between edges of adjacent frames (namely, a frame i and a frame i+1) is calculated.

[0094] (b) All APi values are summed to produce a total pixel displacement APtotal, which is referred to as APt below for simplified description.

[0095] (c) D3 is divided by the total pixel displacement APt to produce a conversion ratio K, that is, K = D3 / APt. If the distortion control of a lens of a supplier is unsatisfactory, a K value should also be adjusted by adding compensation and calibration coefficients to each quadrant, but this method is not recommended. In principle, the hardware of a supplier should be strictly checked.

[0096] (d) AD = K * APi (APi is a pixel position difference between adjacent frames) and AT = 1 / operating frame rate of the camera are calculated.

[0097] Curve plotting: A time T is set as an x-coordinate, a displacement distance D is set as a y-coordinate, and a starting point of a curve is set as an origin (Tl, DI) for coordinate axes, where a Tl point represents a time point when the cage is not displaced at the moment of detaching and a DI point represents a measured value of the laser ranging module produced in the S5. Each point in a coordinate system is determined according to a calculated actual displacement distance value AD of each cage edge and a time interval AT between two frames, and resulting points are connected successively to plot a curve A of a change of a distance over time. Finally, the curve produced after the points are connected is displayed on the display screen. D2 is an end point of the curve. D3 represents a difference between D2 and DI, that is, an actual displacement of the cage before and after an action of a mining cage fall arrester. T2 represents a stop point of a movement of the cage.

[0098] An expected curve is plotted according to a law of v = gt, that is, D = 0.5 gtA2, as shown in FIG. 6. A separation point of the two curves is (Tx, Dx). A D value of an overlapped part of the two curves is an idle travel distance, that is, DI to Dx is an idle travel distance. A T value of the overlapped part of the two curves is an idle motion time, that is, Tl to Tx is an idle travel time. Dx to D2 is a deceleration distance, and Tx to T2 is a deceleration time.

[0099] S9: The output of the display screen is restored and displayed. The curves are output in a picture format and stored in the same folder as a current video. The folder is named after a location and time recorded by the GPS. A difference between a factory test value and an actual measured value of DC - DI or DC2 - DI is output next to the curves, which provides a basis for determining whether a measurement is valid.

[0100] Distance data at each time point is stored as a text file. Each line of the text file shows an x-coordinate and a y-coordinate of a point, and the coordinates are followed by time information. The text file is stored in the same folder as the curve picture, and the text file is in an ASCII encoding form.

[0101] After the above measurement is completed, the blue indicator light is on to indicate that the detection is completed. Moreover, memory resources are released, and a frequency of CPU is reduced to a standby frequency.

[0102] In the above method, when an indicator light is on, it means that only this indicator light is on and all other indicator lights are off. When an indicator light is on, the indicator light is always on, and a state of the indicator light will be maintained without additional requirements. The parameters mentioned in the method all represent the optimal values, and the technicians have provided a lot of tests and labor for the screening of the specific data. In this solution, the parameters are fixed parameters and should also be followed in production, and the arbitrary changes of the parameters will cause uncontrollable impacts on the overall measurement results.

[0103] The use and operation of the apparatus are described in detail below:

[0104] 1 A power button at the top is pressed, such that the apparatus is started and the display of the screen of the apparatus is started. About 8 s later, the starting of the apparatus is completed, and a fill light module is on. The camera is started, and real-time video information captured by the camera is displayed on the screen (at this point, a sampling rate of the camera is a screen refresh rate).

[0105] 2. The neodymium magnet plated with gold on a back side is adsorbed to a rigid metal connection frame of a detacher or a fixed detacher, and cannot be adsorbed to a movable component, which should ensure that the apparatus does not move and shake when working. If an on-site situation cannot meet this requirement, a special bracket for fixing the apparatus can be additionally provided. The mode switch needs to pressed, and in system settings, a forced vertical mode is turned on. If the forced vertical mode is not selected, the apparatus will work in a horizontal mode when the mode switch is pressed. The mode switch is a physical switch connected to the wireless power amplifier inside the apparatus. The mode switch can switch a signal between the SMA interface and the gold-plated neodymium magnet. After switching to the SMA interface, an extended feeder can be directly connected to the detacher through the SMA interface.

[0106] 3 An angle of the apparatus is adjusted, such that the camera faces a top of a cage. Four sides of the top of the cage should be seen on the display screen. If an arrangement angle does not meet the requirements, the apparatus should be removed and adjusted, and should not be rotated directly when the apparatus is adsorbed. In order to ensure a fixation effect, a strap can also be used for fixation along a groove of the strap-fixing region of the apparatus, but it must be ensured that the neodymium magnet on the back side is adsorbed as required in the step 2. After the adsorption is completed, an adsorption and fitting state of the magnet should be checked through the optical observation window. If there is a light leakage at an adsorption and fitting site, it indicates that the adsorption and fitting is incomplete, and the apparatus needs to be adjusted to a smooth plane meeting requirements for arranging.

[0107] 4. After the arrangement of the apparatus is completed, a start button is clicked, the prompt voice "please wait when the apparatus is ready to start calibration" is given, and the yellow indicator light is on. At this time point, the apparatus cannot be moved. If there is a too-large vibration on site, it is also necessary to coordinate the on-site situation accordingly. The use of a heavy device or a blasting operation that will cause a strong environmental vibration is prohibited during a working process of the apparatus. The apparatus requires a calibration and detection time of about 2 min, and the calibration of the apparatus can be completed within 1 min. It takes less than 1 min for a tester to select intelligently-identified edges.

[0108] 5. After the green indicator light is on, it indicates that the preheating is completed and the apparatus is ready. Under the conditions of ensuring the safety, the detaching can be conducted immediately to release the cage, so as to complete a mining cage fall arrester test.

[0109] 6. After the detaching test is completed, a tester can print an operation result. The test information such as a measurement result of a braking distance can be transmitted to the external portable printer through the 433M communication output module with the universal serial transmission protocol, and a report and a certificate can be directly printed on site. The portable printer is not included in the apparatus kit and needs to be purchased separately.

[0110] 7. Description of indicator lights: The red indicator light indicates a fault, and a specific fault situation can be viewed on the screen. The yellow indicator light indicates preheating and calibrating, during which the apparatus must not be moved. The green indicator light indicates that the preparation is completed and the apparatus is working. The blue indicator light indicates the end of testing.

[0111] 8. By default, the apparatus carries a charger and a memory card. The TF memory card has been initialized and arranged in the apparatus, and should not be taken out unless necessary.

[0112] Due to restrictions of the on-site conditions, the apparatus can also be arranged horizontally relative to the cage for measuring, but only a semi-automatic state can be maintained, which will lead to a declined accuracy. Moreover, a mode needs to be switched manually, and a signal feeder is connected to the detacher through the SMA interface on the top of the apparatus. DI and D2 are no longer measured, DC and DC2 are no longer verified, and images of at least three edges of a side of the cage before and after the detaching need to fall in the field of vision of the camera. A D3 value needs to be measured manually on site and then input into the apparatus, and an output result is printed: horizontal mode identity. The horizontal mode is available to a user only as an auxiliary function, and a non-recommended function identity is printed in the manual for the apparatus.

[0113] The apparatus needs to be used in combination with a metal rigid detacher, and the apparatus should be static and stable when in use.

[0114] The detachment test in the default mode has high sensitivity. The default mode is suitable for most scenarios, and has a strong anti-interference ability. The default mode should not be switched unless necessary. The strict mode can be used in strict important places due to the addition of verification, but requires a clean on-site radio environment. Thus, the strict mode is suitable for important remote mining areas with relatively-clean radio environments.

[0115] The measuring apparatus has a reasonable design, allows scientific measuring, and solves the shortcomings of single measurement modes of the existing measuring apparatuses. All aspects of the measuring apparatus support each other to comprehensively improve the overall function of the measuring apparatus.

Claims

1. A measurement apparatus for a braking distance of a mining cage fall arrester, comprising a housing (1), wherein a front side of the housing (1) is provided with an optical observation window (3), the optical observation window (3) runs through the entire housing (1), and the housing (1) is provided with an inclined reflecting mirror (4) at a position of a hole behind the optical observation window (3);the front side of the housing (1) is further provided with a display screen (2), a plurality of indicator lights (5), functional operation buttons (6), a mode switch (7), a memory card socket (8), and a data transmission interface (9);a cubic neodymium magnet (10) is provided at a back side of the housing (1) and below the reflecting mirror (4); a surface of the neodymium magnet (10) is plated with gold; five sides of the neodymium magnet (10) each are wrapped with 1 mm polytetrafluoroethylene, and the polytetrafluoroethylene is wrapped with a metal shielding layer externally; the neodymium magnet (10) is connected to a core of a feeder, and the metal shielding layer is connected to a shielding layer of the feeder; and the neodymium magnet (10) protrudes from the back side of the housing (1);a bottom of the housing (1) is provided with a concave region that is closed with a transparent optical sapphire cover plate (12); an optical glass column (11), a laser ranging module (13), a measuring light-emitting diode (LED) fill light module (14), a camera module (15), and a trapezoidal metal shielding enclosure (16) flared outwards are provided at an inner side of the cover plate; a peripheral side of the optical glass column (11) is frosted, and two ends of the optical glass column are glossy; and one glossy end of the optical glass column is bonded to the transparent optical sapphire cover plate (12), and the other glossy end of the optical glass column is bonded to a laser-emitting head of the laser ranging module (13); anda central control module (17), a Global Positioning System (GPS) module (18), an active ceramic GPS antenna (19), a wireless receiving module (20), a wireless transmitting module (21), a 315M control module (22), a 433M communication output module (23), a 9-axis accelerometer and gyroscope module (24), and a speaker module (26) are provided inside the housing (1); the central control module (17) comprises an input signal bus and an output signal bus; the GPS module (18), the laser ranging module (13), the wireless receiving module (20), the camera module (15), the 9-axis accelerometer and gyroscope module (24), the 315M control module (22), and thefunctional operation buttons (6) each are connected to the input signal bus (37); and the display screen (2), the wireless transmitting module (21), the plurality of indicator lights (5), the 433M communication output module (23), the speaker module (26), the measuring LED fill light module (14), and an observing LED fill light module (28) each are connected to the output signal bus (36).

2. The measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, wherein left and right sides of the housing (1) each are provided with a breaking-proof rubber edge trim (32) that is made of a polyurethane (PU) material and protrudes from a surface of a body of the apparatus; each breaking-proof rubber edge trim is provided with a removal groove (33) at both upper and lower positions; and a middle of each breaking-proof rubber edge trim (32) is provided with a strap-fixing region (34) that is recessed towards a center of the body of the apparatus and is configured to embed and fix a strap.

3. The measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, wherein the plurality of indicator lights (5) are arranged above the optical observation window (3), and are as follows from left to right sequentially: a yellow indicator light, a green indicator light, a blue indicator light, and a red indicator light; the yellow indicator light indicates preheating, the green indicator light indicates working, the blue indicator light indicates an ending, and the red indicator light indicates a fault; and when the red indicator light is on, all programs and detection actions are terminated until the apparatus is manually restarted.

4. The measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, wherein a middle of the back side of the housing is provided with a trapezoidal prism (27); the neodymium magnet (10) is arranged in a recessed region of the trapezoidal prism (27), and the neodymium magnet (10) protrudes from the back side of the housing by 0.5 mm; the apparatus further comprises the observing LED fill light module (28) that is arranged in a strip-like protruded region below the neodymium magnet (10) and irradiates the neodymium magnet (10) above; and the observing LED fill light module (28) is connected to the output signal bus (36).

5. Claim 5. The measurement apparatus for a braking distance of a mining cage fallarrester according to claim 1, wherein a top of the housing is provided with a recessed region, and a power switch (29), a charging interface (30), and a SubMiniature version A (SMA) interface (31) are provided from left to right sequentially in the recessed region; and the mode switch (7) is connected to a power amplifier (25), and the power amplifier is connected to the wireless transmitting module (21).

6. The measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, wherein there are three metal shielding enclosures (16) that are nested, parallel to each other, insulated from each other, and 1 mm spaced from each other; an innermost metal shielding enclosure is connected to the shielding layer of the feeder of the wireless receiving module (20); the innermost metal shielding enclosure comprises a chip directional antenna (35); the innermost metal shielding enclosure is insulated from the chip directional antenna (35), and the chip directional antenna is connected to the wireless receiving module (20) through the core of the feeder; and a built-in wireless radio frequency power detection module (201) is provided in the wireless receiving module (20).

7. The measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, wherein the 9-axis accelerometer and gyroscope module (24) integrates a 3-axis accelerometer, a 3-axis magnetometer, and a 3-axis gyroscope; the 9-axis accelerometer and gyroscope module has a static attitude measurement accuracy not exceeding 0.05° and a dynamic attitude measurement accuracy not exceeding 0.1°, comprises a built-in Kalman attitude determination algorithm, and has a magnetometer ellipsoid correction function; and Aacceleration represents an acceleration fluctuation variable, A3-axis gyroscope data represents an X, Y, and Z axis fluctuation variable, and Aellipsoid magnetic data represents a magnetometer data fluctuation variable after an ellipsoid fitting algorithm.

8. A measurement method based on the measurement apparatus for a braking distance of a mining cage fall arrester according to claim 1, comprising the following steps:1) arranging the apparatus at a measuring position as required, checking an adsorption state through the optical observation window, and selecting a corresponding measuring mode;2) starting a power supply such that the yellow indicator light of the apparatus is on; performing a cold start for the GPS module (18) while broadcasting a prompt voice comprising a required distance between personnel and the apparatus; after the broadcasting of the prompt voice is completed, powering the 9-axis accelerometer and gyroscope module (24) on to enter a working state; acquiring acceleration data, 3-axis gyroscope data, and magnetometer data after the ellipsoid fitting algorithm in real time, and recording GPS data acquired by the GPS module (18); and calibrating a time of the apparatus according to a time acquired by the GPS module (18);3) calculating Aacceleration, A3-axis gyroscope data, and Aellipsoid magnetic data; when the Aacceleration and the A3-axis gyroscope data are less than 0.1% and Aellipsoid magnetic data is less than 1% within 5 s, directly entering the next step; when the Aacceleration and the A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, repeating the calculating with a 5 s delay, and iterating for no more than 5 times; when there are more than 5 times of the iterating or Aacceleration and A3-axis gyroscope data in a single time are greater than 0.3% and less than 0.6%, prompting to check an environmental vibration factor, and making the red indicator light on;4) executing a single-threaded monitoring task, directly entering the next step, and terminating the single-threaded monitoring task when a movement of a cage is detected, wherein the single-threaded monitoring task has a delayed error-reporting function; and if a movement of the cage is detected, delayed error reporting is terminated, a subsequent error-reporting action is no longer executed, and the single-threaded monitoring task is terminated;5) powering the wireless transmitting module (21), the power amplifier (25), and the wireless receiving module (20) on; detecting and setting an optimal channel, performing statistical analysis on signal intensities of effective coding signals, and counting and calculating an average value, a standard deviation, and a range for signal intensities dbm received within 5 s; when a ratio of the standard deviation to the average value for the signal intensities dbm does not exceed 0.5%, that is, the standard deviation / average value is less than or equal to 0.5%, and a ratio of the range to the average value for the signal intensities dbm does not exceed 5%, that is, the range / average value is less than or equal to 5%, directly entering the next step, otherwise prompting to report an error by the display screen (2), comprising two types of errors; if the range / average value is more than or equal to 10%, reporting an errorprompting that a signal receiving and transmitting module is suspected to be faulty; and for situations other than the above situation, collectively reporting an error prompting that there is a radio interference to be eliminated on site, and making the red indicator light on;6) setting a sampling rate of a camera to a rated operating frame rate, and loading data captured by the camera into a random access memory (RAM) of a central controller; denoising information of a top of the cage that is captured by the camera, smoothing an image with a Gaussian filter, and calculating a gradient intensity and direction of each pixel in the image with a Sobel operator; conducting a maximum detection in the gradient direction; only retaining pixels with a maximum gradient; dividing the pixels into strong edges, weak edges, and non-edges; directly outputting the strong edges, directly discarding the non-edges, and outputting the weak edges only when the weak edges are connected to the strong edges; connecting the weak edges to the strong edges with a connectivity analysis algorithm to produce complete edges, and dividing the complete edges into single line segments along an intersection point; selecting and marking line segments for an edge of the cage that meet requirements by a tester with a 315M wireless controller; after the selection is determined by the tester, recording length and coordinate position information of the current line segments for the edge of the cage in image data, measuring a distance from the apparatus to the top of the cage by the laser ranging module, recording the distance as DI, and making the green indicator light on to indicate that the apparatus is ready; prompting by the display screen (2) that a detachment test is able to be conducted; continuing the sampling by the camera at the rated operating frame rate, and writing sampled video data into the RAM in real time with a low resource consumption strategy; and retaining only the first 1,000 ms high-speed video data in the RAM, and overwritting high-speed video data circularly, wherein video information in the RAM exists in a form of raw data and does not undergo additional analysis and coding by a central processing unit (CPU);7) executing a program in a default mode if there are no settings, or executing the program in a strict mode according to settings of a user if any; and in both modes, directly entering the next step after a corresponding program is normally terminated, wherein the program in the default mode is characterized in that: when a change of a current coding signal intensity is ±20% greater than an average coding signal intensity and fails to be restored to the average coding signal intensity, a time when an instantaneous change occurs is taken as Tl, and regardless of whether the coding signalintensity is restored, the laser ranging module is linked for ranging at the time Tl when the coding signal intensity dbm changes instantaneously, and a ranging result is recorded as DC; if the coding signal intensity is not restored after 500 ms, the program execution is terminated normally; and if the change of the coding signal intensity dbm is more than ±20% of the average coding signal intensity, but is able to be restored to 5% or less of the average coding signal intensity within 500 ms, a user is prompted that the signal receiving and transmitting module is faulty probably, error reporting is executed, T1 and DC variables are cleared, and the red indicator light is on;8) stopping the low resource consumption strategy of the camera and the video data overwritting strategy of the RAM, such that sampled video data recorded in real time in the RAM is not overwritten; increasing a clock speed of the CPU to a maximum clock speed, stopping an output of the display screen, and releasing memory resources occupied by displaying of the display screen; analyzing and processing video data in real time, and adding a marker to a video frame at the time Tl; detecting a motion state of a "cage edge" with an optical flow algorithm; when the "cage edge" stops changing, recording a current time as T2; adding a marker to a video frame at the time T2, linking the laser ranging module (13) for ranging, and recording a ranging result as D2; and stopping capturing of the camera and writing of a video into the RAM, compressing and storing a sampled video in a H.265 format in a read-only memory (ROM), and embedding GPS metadata acquired by the GPS module into a video fde;9) calculating D2 - DI = D3; analyzing a video stream frame by frame; finding cage edges according to length and coordinate position information for line segments of marked cage edges; tracking and identifying a cage edge in each frame with a mean-shift algorithm; and tracking and recording a pixel position change of the cage edge in each frame, and calculating an actual displacement:(a) calculating a pixel position difference APi between cage edges at a frame i and a frame i+1,(b) summing all APi values to produce a total pixel displacement APt,(c) dividing D3 by the total pixel displacement APt to produce a conversion ratio K, that is, K = D3 / APt, and(d) calculating AD = K * APi and AT = 1 / an operating frame rate of the camera;10) curve plotting: setting a time T as an x-coordinate, a displacement distance D as a y-coordinate, and a starting point of a curve as an origin (Tl, DI) for coordinate axes, wherein a Tl point represents a time point when the cage is not displaced at the momentof detaching and a DI point represents a measured value of the laser ranging module when the cage does not move; determining each point in a coordinate system according to a calculated actual displacement distance value AD of each cage edge and a time interval AT between two frames, and connecting resulting points successively to plot a curve A of a change of a distance over time, wherein D2 is an end point of the curve; D3 represents a difference between D2 and DI, that is, an actual displacement of the cage before and after an action of a mining cage fall arrester; and T2 represents a stop point of a movement of the cage; and plotting an expected curve according to a law of v = gt, that is, D = 0.5 gtA2, wherein a separation point of the two curves is (Tx, Dx); a D value of an overlapped part of the two curves is an idle travel distance, that is, DI to Dx is an idle travel distance; a T value of the overlapped part of the two curves is an idle motion time, that is, T1 to Tx is an idle travel time; and Dx to D2 is a deceleration distance, and Tx to T2 is a deceleration time; and11) restoring the output of the display screen, outputting and displaying the curves in a picture format, and storing the curves in the same folder as a current video, wherein the folder is named after a location and time recorded by the GPS; and outputting a difference between DC and DI or a difference between DC2 and DI, prompting personnel to check the difference, and making the blue indicator light on.

9. The measurement method according to claim 8, wherein in the step 4), when the △acceleration and A3-axis gyroscope data are greater than 0.1% and less than or equal to 0.3%, counting is conducted once; if the counting is conducted 5 times or the △acceleration and △3-axis gyroscope data in a single time are greater than 0.3%, an error-reporting delay is started, and with a 1,500 ms delay, an error is reported, a prompt that there is a too-large vibration to be eliminated and whether the apparatus is fixed at a rigid connection needs to be manually confirmed is given, and the red indicator light is on.

10. The measurement method according to claim 8, wherein the step 7) further comprises the following steps:1) preprocessing signals, and selecting the strongest signal in a selected working channel as a valid signal to be selected;2) verifying a check bit for the valid signal to be selected, and after the verification is successful, recording the valid signal to be selected as a valid signal, and calculating aproportion of invalid signals in total signals in real time;3) if the proportion of invalid signals is greater than 0.1%, directly reporting an error to prompt a user that there is a poor radio environment on site and signal interference needs to be eliminated or a default mode is selected for detection, and after the error reporting, terminating the step and making the red indicator light on;4) if there is no error reporting, further verifying the valid signal, and checking whether a code number of a file header for the valid signal is consecutively related to a code number for the previous signal; if consecutive, then conducting effective counting, and when the effective counting is conducted 10,000 times, jumping to execute the next step to calculate and count time information of a coding signal; if not consecutive, interrupting the counting; and if a number of times to interrupt the counting accumulates to 10, reporting an error to prompt that there is an interference for a channel or poor adsorption of the magnet to be eliminated, and making the red indicator light on; and5) calculating a difference between time information carried by a valid coding signal received each time and a current system time in the valid signal, which is referred to as "difference" in the follow-up description; taking an average value of 10,000 differences, which is referred to as an "average" in the follow-up description; comparing a difference received each time with the average; when difference changes in three times are more than ±10% of the average, taking a time when an instantaneous change of time information is first detected as Tl, and regardless of whether a difference continues to change, linking the laser ranging module for ranging at the time Tl when a change of time information carried by the valid coding signal is first detected, and recording a ranging result as DC2; if a difference change still exceeds ±10% of the average subsequently, normally terminating the program execution; if a difference change is restored to ±10% or less of the average, continuing the time average comparison strategy, clearing Tl and DC2 variables, and making the green indicator light flashed to prompt that there is poor contact adsorption of the magnet probably.

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