Sightseeing car braking distance detection system and method

Abstract

The embodiment of the present application provides a sightseeing car braking distance detection system and method. Combined with the detection of the brake pedal inclination angle, the distance data at the start and end of braking are determined to realize the braking distance detection of the sightseeing car, which can effectively improve the detection accuracy. Among them, the system includes a wireless ranging module, a pedal inclination sensing module, a vehicle-mounted module, and a braking distance detection host. The wireless ranging module includes a first base station and a second base station, and the pedal inclination sensing module is fixedly installed on the side of the brake pedal of the sightseeing car to detect the inclination angle of the brake pedal. When the pedal inclination sensing module senses that the inclination angle of the brake pedal reaches different inclination conditions at different times, the vehicle-mounted module is triggered to measure the distance between the sightseeing car and the first base station and the second base station at each of the different times and send the measured distance to the braking distance detection host to detect the braking distance of the sightseeing car.

Description

Technical Field

[0001] The present application relates to the technical field related to special equipment detection, and in particular, to a sightseeing vehicle braking distance detection system and method. Background Art

[0002] With the continuous improvement of people's living standards, the national tourist groups are becoming larger and larger, and the number of people is increasing. In many tourist attractions, sightseeing cars have almost become standard. They can transport tourists short distances within the scenic area, bringing great convenience. Therefore, the driving safety of sightseeing cars is particularly important. As the most important performance indicator in the driving safety of sightseeing cars, braking distance must be tested during the regular on-site inspection of sightseeing cars. However, the inventors found through investigation and research that traditional detection methods such as those based on ground brake tire marks have low accuracy in detecting braking distance, which is not conducive to accurately evaluating the braking safety of sightseeing cars, so that sightseeing cars still have certain safety hazards, which is not conducive to social safety and stability. Therefore, there is an urgent need for a fast and high-precision braking distance detection method for sightseeing cars. Summary of the invention

[0003] Based on the above, in a first aspect, an embodiment of the present application provides a braking distance detection system for a sightseeing car, the system comprising a wireless distance measurement module, a pedal inclination sensing module, a vehicle-mounted module, and a braking distance detection host, the wireless distance measurement module comprising a first base station and a second base station arranged according to the braking position of the sightseeing car during braking detection, the vehicle-mounted module is communicatively connected with the first base station and the second base station, the pedal inclination sensing module is fixedly installed on the side of the brake pedal of the sightseeing car to detect the inclination of the brake pedal;

[0004] Among them, the vehicle-mounted module is communicatively connected with the pedal inclination sensing module. When the pedal inclination sensing module senses that the inclination angle of the brake pedal reaches different inclination conditions at different times, the vehicle-mounted module is triggered to measure the distance between the sightseeing vehicle and the first base station and the second base station at each of the different times and send the measured distance to the braking distance detection host to detect the braking distance of the sightseeing vehicle.

[0005] In a possible implementation manner of the first aspect, the vehicle-mounted module includes a first positioning tag, a second positioning tag, and a speed detection unit that are arranged corresponding to the brake pedal of the sightseeing vehicle, the first positioning tag and the second positioning tag are respectively connected to the first base station and the second base station for communication,

[0006] The vehicle-mounted module measures the distance between the sightseeing vehicle and the first base station through the first positioning tag and measures the distance between the sightseeing vehicle and the second base station through the second positioning tag at each of the different moments.

[0007] Based on a possible implementation of the first aspect, the pedal inclination sensing module includes a fixing device and an inclination sensor, and the inclination sensor is fixedly installed on the side of the brake pedal through the fixing device; wherein the fixing device includes a fixing plate and a Velcro assembly, the inclination sensor is fixed on the fixing plate, and the fixing plate is fixed to the side of the brake pedal through the Velcro assembly.

[0008] Based on a possible implementation of the first aspect, the Velcro assembly includes a first Velcro tape mounted on the brake pedal along a first direction and a second Velcro tape mounted on the brake pedal along a second direction, the fixing plate includes a first fixing portion and a second fixing portion, the first fixing portion extends along the first direction and is fixed to the brake pedal by the first Velcro tape, the second fixing portion extends along the second direction and is fixed to the brake pedal by the second Velcro tape, and the first direction intersects with the second direction.

[0009] In a possible implementation manner of the first aspect, the pedal inclination angle sensing module is used to send first inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is greater than a first inclination angle threshold;

[0010] The vehicle-mounted module is used for measuring and obtaining a first distance between the sightseeing vehicle and the first base station and a second distance between the sightseeing vehicle and the second base station upon receiving the first inclination angle data;

[0011] The pedal inclination angle sensing module is further used to send second inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is restored to the second inclination angle threshold;

[0012] The vehicle-mounted module is further used to measure a third distance between the current sightseeing vehicle and the first base station and a fourth distance between the sightseeing vehicle and the second base station when receiving the second inclination angle data, and send the measured distance data to a braking distance detection host, wherein the measured distance data includes the first distance, the second distance, the third distance and the fourth distance;

[0013] The braking distance detection host is used to detect and obtain the braking distance of the sightseeing vehicle according to the distance data.

[0014] In a second aspect, an embodiment of the present application further provides a sightseeing vehicle braking distance detection method, which uses the above-mentioned sightseeing vehicle braking distance detection system to detect the braking distance of the sightseeing vehicle, and the method includes:

[0015] The pedal inclination angle sensing module sends first inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is greater than a first inclination angle threshold;

[0016] When receiving the first inclination angle data, the vehicle-mounted module measures and obtains a first distance between the sightseeing vehicle and the first base station and a second distance between the sightseeing vehicle and the second base station;

[0017] The pedal inclination angle sensing module sends the second inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is restored to the second inclination angle threshold;

[0018] When receiving the second inclination angle data, the vehicle-mounted module measures a third distance between the current sightseeing vehicle and the first base station and a fourth distance between the sightseeing vehicle and the second base station, and sends the measured distance data to a braking distance detection host, wherein the measured distance data includes the first distance, the second distance, the third distance and the fourth distance;

[0019] The braking distance detection host detects and obtains the braking distance of the sightseeing vehicle according to the distance data.

[0020] Based on a possible implementation of the second aspect, the braking distance of the sightseeing vehicle is calculated by the following formula:

[0021]

[0022]

[0023]

[0024] Among them, θ2=θ3-θ1, A0B is the first distance, A0C is the second distance, A2B is the third distance, A2C is the fourth distance, BC is the distance between the first base station and the second base station, and A0A2 is the braking distance of the sightseeing car.

[0025] According to a possible implementation manner of the second aspect, the vehicle-mounted module further includes an acceleration sensor, and the method further includes:

[0026] At the moment when the sightseeing vehicle starts braking, the vehicle-mounted module measures the current first acceleration value a1 of the sightseeing vehicle through the acceleration sensor, and calculates the current first speed V1 of the sightseeing vehicle.

[0027] At the moment of full braking of the sightseeing vehicle, the vehicle-mounted module measures the current second acceleration value a of the sightseeing vehicle through the acceleration sensor. mand sending speed data to the braking distance detection host, wherein the speed data includes the first acceleration value a1, the first speed V1, the second acceleration value a m , and a preset standard braking speed V0 of the sightseeing vehicle;

[0028] The braking distance detection host corrects the braking distance of the sightseeing vehicle according to the speed data;

[0029] The braking distance detection host corrects the braking distance of the sightseeing vehicle by the following formula:

[0030]

[0031] Among them, S0 is the braking distance, S is the corrected braking distance; the starting braking moment is the moment when the pedal inclination sensing module detects that the inclination angle of the brake pedal is greater than the first inclination angle threshold, and the full braking moment is the moment when the pedal inclination sensing module detects that the inclination angle of the brake pedal reaches the third inclination angle threshold.

[0032] In a possible implementation manner of the second aspect, the pedal inclination angle sensing module includes a three-axis acceleration sensor; wherein, before starting the braking distance detection of the sightseeing vehicle, the method further includes an initialization step of the pedal inclination angle sensing module, and the initialization step includes:

[0033] Prompting the inspector to perform an initialization operation on the brake pedal of the sightseeing vehicle, wherein the initialization operation includes pressing the brake pedal to the deepest position according to a set operation mode, and then gradually releasing the brake pedal to prevent the brake pedal from being stepped off;

[0034] During the above initialization operation, the pedal inclination sensing module detects the acceleration values ​​in the X-axis and Z-axis directions through the three-axis acceleration sensor, calculates the real-time inclination of the brake pedal, and obtains the minimum inclination and maximum inclination of the brake pedal of the sightseeing car;

[0035] The first tilt angle threshold, the second tilt angle threshold, and the third tilt angle threshold are initialized according to the minimum tilt angle and the maximum tilt angle.

[0036] According to a possible implementation manner of the second aspect, the method further includes:

[0037] The inclination angle of the brake pedal is collected in real time by the inclination sensor of the pedal inclination sensing module, and the time taken for the inclination angle of the brake pedal to increase from the first inclination angle threshold to the third inclination angle threshold is calculated as the braking force establishment time, and whether the braking operation in the braking distance detection process of the sightseeing vehicle is effective is judged according to the braking force establishment time; wherein, when the braking force establishment time is less than the set time threshold, the braking operation is judged to be effective, otherwise, the braking operation is judged to be invalid;

[0038] When it is determined that the braking operation is valid, the braking distance detection host displays the corrected braking distance; when it is determined that the braking operation is invalid, a prompt message of invalid braking is issued to prompt that the current detection result is invalid.

[0039] In summary, the sightseeing car braking distance detection system and method provided by the embodiment of the present application, combined with the detection of the brake pedal inclination angle, determines the distance data at the start and end of braking to realize the braking distance detection of the sightseeing car, which can effectively improve the detection accuracy. At the same time, the detection of the relevant moments such as the start and end of braking during the braking process adopts the method of placing the pedal inclination sensing module on the side of the brake pedal, which can reflect the entire process of stepping on the brake pedal, improve the detection accuracy of the braking distance, and greatly improve the safety during the braking distance detection and test process.

[0040] Furthermore, the embodiments of the present application combine the correction of braking distance, elimination of vehicle motion interference and other means to further improve the accuracy of the braking distance detected, eliminate the safety hazards of sightseeing vehicles, and improve the safety of sightseeing vehicles. In addition, the influence of factors such as shaking, side slip, skidding, and driving habits on the braking distance results can be further avoided during the braking process. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a schematic diagram of a sightseeing vehicle braking distance detection system provided in an embodiment of the present application.

[0043] Figure 2 It is a schematic diagram of the layout scenario of the above sightseeing car braking distance detection system and the sightseeing car.

[0044] Figure 3 yes Figure 2An enlarged schematic diagram of the pedal inclination sensing module installed on the brake pedal of the medium sightseeing car.

[0045] Figure 4 It is a top view of a pedal inclination angle sensing module installed on a brake pedal provided in an embodiment of the present application.

[0046] Figure 5 This is a front view of a pedal inclination sensing module installed on a brake pedal provided in an embodiment of the present application.

[0047] Figure 6 It is a side view of a pedal inclination angle sensing module installed on a brake pedal provided in an embodiment of the present application.

[0048] Figure 7 It is a flow chart of a sightseeing vehicle braking distance detection method provided in an embodiment of the present application.

[0049] Figure 8 It is a schematic diagram of the principle of calculating the braking distance of the sightseeing car in the embodiment of the present application.

[0050] Fig. 9 It is a schematic diagram of the principle of correcting the braking distance in an embodiment of the present application.

[0051] Fig.10 It is a schematic diagram of the principle of braking distance analysis and test effectiveness inspection in the embodiment of the present application.

[0052] Fig.11 It is a schematic diagram of the principle of brake pedal inclination angle detection during system initialization in an embodiment of the present application.

[0053] Fig.12 It is a schematic diagram of the principle of eliminating vehicle motion interference in an embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0055] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0056] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0057] In the description of the present application, the terms “first”, “second”, “third”, etc. are only used to distinguish the descriptions and should not be understood as indicating or implying relative importance.

[0058] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] Before introducing the relevant technical solutions provided by the embodiments of the present application in detail, in order to more clearly understand the relevant technical solutions of the embodiments of the present application, the relevant technical terms involved in the embodiments of the present application are first explained.

[0060] Based on the technical problems mentioned in the above background technology, the inventors investigated and studied the braking distance detection methods of other types of vehicles similar to sightseeing vehicles and found that the existing braking distance detection methods on other motor vehicles also have some problems to a greater or lesser extent.

[0061] For example, a solution that uses a laser rangefinder to detect the braking distance of a vehicle in real time can achieve a higher detection accuracy, but this method requires a larger measuring plate to be installed at the rear end of the vehicle to meet the distance detection when the laser rangefinder is far away from the vehicle. For another example, the braking distance can also be detected by installing a passive wheel device with a distance detection function on the vehicle. Although this method can achieve a higher detection accuracy, it is difficult to fix on vehicles such as sightseeing cars and has poor versatility. In addition, the braking process is only detected by the brake switch, which makes the installation complicated and cannot reflect the entire process of stepping on the brake pedal, and the braking accuracy is limited.

[0062] Based on this, the embodiment of the present application innovatively provides a sightseeing car braking distance detection system and method, which combines the detection of the brake pedal inclination angle to determine the distance data at the start and end of braking to realize the braking distance detection of the sightseeing car. In this way, the influence of factors such as shaking, side slipping, sliding, driving habits, etc. in the braking process on the braking distance results can be effectively avoided, and the detection accuracy can be improved. At the same time, the detection of relevant moments such as the start and end of braking during the braking process adopts the method of placing an inclination sensor on the side of the brake pedal, which can reflect the entire process of stepping on the brake pedal, improve the detection accuracy of the braking distance, and greatly improve the safety during the braking test.

[0063] The following is an introduction to the sightseeing vehicle braking distance detection system and method provided in the embodiments of the present application in conjunction with the accompanying drawings.

[0064] like Figure 1 , which is a schematic diagram of a sightseeing car braking distance detection system provided by an embodiment of the present application. In this embodiment, the sightseeing car braking distance detection system may include a wireless distance measurement module 100, a pedal inclination sensing module 200, a vehicle-mounted module 300, and a braking distance detection host 400.

[0065] Combination Figure 2 and Figure 3 As shown, the wireless distance measurement module 100 includes a first base station 101 and a second base station 102 which are arranged according to the braking position of the sightseeing vehicle during braking detection, and the vehicle-mounted module 300 is in communication connection with the first base station 101 and the second base station 102. The pedal inclination sensing module 200 is fixedly mounted on the side of the brake pedal of the sightseeing vehicle to detect the inclination of the brake pedal.

[0066] The vehicle-mounted module 300 is in communication connection with the pedal inclination sensing module 200. When the pedal inclination sensing module 200 senses that the inclination of the brake pedal reaches different inclination conditions at different times, the vehicle-mounted module 300 is triggered to measure the distance between the sightseeing vehicle and the first base station 101 and the second base station 102 at each different time and send the measured distance to the braking distance detection host 400 to detect the braking distance of the sightseeing vehicle. In a possible implementation, the braking distance detection host 400 can be, but is not limited to, a personal computer, a laptop computer, a server, or other equipment with data calculation and processing capabilities.

[0067] In a possible implementation, the vehicle-mounted module 300 may include a first positioning tag, a second positioning tag, and a speed detection unit that are set corresponding to the brake pedal of the sightseeing car, and the first positioning tag and the second positioning tag are respectively connected to the first base station 101 and the second base station 102. For example, the first positioning tag is connected to the first base station 101, and the second positioning tag is connected to the second base station 102. In a possible implementation, the first base station 101 and the second base station 102 can be, but not limited to, UWB (UltraWide Band) base stations, and accordingly, the first positioning tag and the second positioning tag can be UWB positioning tags. In another possible implementation, a third positioning tag corresponding to the first positioning tag can be set on the first base station 101, and a fourth positioning tag corresponding to the second positioning tag can be set on the second base station 102.

[0068] The vehicle-mounted module 300 can measure the distance between the sightseeing vehicle and the first base station 101 through the first positioning tag and measure the distance between the sightseeing vehicle and the second base station 102 through the second positioning tag at each of the different times.

[0069] like Figure 4 As shown, the pedal inclination sensing module 200 may include a fixing device 210 and an inclination sensor 220, and the inclination sensor 220 is fixedly mounted on the side of the brake pedal through the fixing device 210. In a possible implementation, the fixing device 210 may include a fixing plate 211 and a Velcro assembly 212, and the inclination sensor 220 is fixed on the fixing plate 211, and the fixing plate 211 is fixed to the side of the brake pedal through the Velcro assembly 212. Optionally, the Velcro assembly 212 may be, but is not limited to, a nylon Velcro tape.

[0070] Combination Figure 5 and Figure 6As shown, the Velcro assembly 212 may include a first Velcro tape sleeved on the brake pedal along a first direction and a second Velcro tape sleeved on the brake pedal along a second direction, and the fixing plate 211 may include a first fixing portion and a second fixing portion, the first fixing portion extends along the first direction and is fixed to the brake pedal by the first Velcro tape, the second fixing portion extends along the second direction and is fixed to the brake pedal by the second Velcro tape, and the first direction intersects with the second direction. Optionally, the first direction may be perpendicular to the second direction and connected as an integral structure, so that the first fixing portion and the second fixing portion form an L-shaped fixing plate. Preferably, the fixing plate 211 may be, but not limited to, an L-shaped steel plate. In a possible implementation, the pedal inclination sensing module 200 may also include an adhesive structure, and the inclination sensor 220 may be bonded to the fixing plate 211 by the adhesive structure.

[0071] like Figure 7 FIG. 1 is a flow chart of a sightseeing vehicle braking distance detection method provided in an embodiment of the present application. The method is implemented based on the above-mentioned sightseeing vehicle braking distance detection system. Figure 7 Each step of the method is explained exemplarily.

[0072] Step S710 , when the pedal inclination sensing module 200 detects that the inclination of the brake pedal is greater than a first inclination threshold, the pedal inclination sensing module 200 sends first inclination data to the vehicle-mounted module 300 .

[0073] In this embodiment, the first inclination angle data may include, but is not limited to, the current inclination angle of the brake pedal and the time information when it is greater than the first inclination angle threshold. The pedal inclination angle sensing module 200 can detect the inclination angle of the brake pedal in real time when the braking distance detection program of the sightseeing car is started. The state of the brake pedal can be determined by the detection result of the inclination angle, and then the current braking process of the sightseeing car can be determined. For example, at the beginning, the driver (or operator) can drive the sightseeing car and increase the speed. After the speed reaches the set standard braking speed V0 and stabilizes, and the vehicle reaches the vicinity of the intended braking position, the driver transfers his foot from the accelerator pedal to the brake pedal and starts to step on it. Since the brake pedal has a certain idle travel, the braking system of the sightseeing car only starts to actually generate braking force after the inclination angle of the brake pedal is greater than the first inclination angle threshold, and the sightseeing car is at the starting braking time t0. In this case, the first inclination angle threshold can be determined according to the inclination angle of the brake pedal of the sightseeing car at the moment when the braking system starts to generate braking force.

[0074] Step S720: When receiving the first tilt angle data, the vehicle-mounted module 300 measures a first distance between the sightseeing vehicle and the first base station and a second distance between the sightseeing vehicle and the second base station.

[0075] Step S730 , when the pedal inclination sensing module 200 detects that the inclination of the brake pedal is restored to the second inclination threshold, the pedal inclination sensing module 200 sends the second inclination data to the vehicle-mounted module 300 .

[0076] Wherein, in this embodiment, the second inclination angle data may include, but is not limited to, the current inclination angle of the brake pedal and the time information of returning to the second inclination angle threshold. In this embodiment, as the driver drives the sightseeing car and performs the braking operation, as the inclination angle of the brake pedal increases, the braking system gradually reaches the maximum braking force output, and finally until the vehicle is completely stationary. When the vehicle is completely stationary, the driver stops the vehicle and releases the stepping on the brake pedal, so that the brake pedal returns to the original state, and the inclination angle of the brake pedal is less than the preset second inclination angle threshold. Wherein, in this embodiment, the second inclination angle threshold can be preset according to the inclination angle of the brake pedal in the initial state. For example, the second inclination angle threshold can be slightly greater than the initial inclination angle of the brake pedal in the initial state. Wherein, in this embodiment, the first inclination angle threshold is greater than the second inclination angle threshold. The first inclination angle threshold is used to characterize the corresponding position state of the brake pedal when the brake pedal causes the brake system to start outputting braking force, and the second inclination angle threshold is used to characterize the position state of the brake pedal returning to the initial state when the sightseeing car brakes.

[0077] Step S740, when the vehicle-mounted module receives the second inclination angle data, measures the third distance between the sightseeing vehicle and the first base station and the fourth distance between the sightseeing vehicle and the second base station, and sends the measured distance data to the braking distance detection host 400, wherein the measured distance data includes the first distance, the second distance, the third distance and the fourth distance.

[0078] Step S750: the braking distance detection host 400 detects and obtains the braking distance of the sightseeing vehicle according to the distance data.

[0079] Among them, combined Figure 8 FIG. 1 is a schematic diagram showing the principle of calculating the braking distance in an embodiment of the present application. Based on this, in this embodiment, the braking distance of the sightseeing car is calculated by the following formula:

[0080]

[0081]

[0082]

[0083] Among them, θ2=θ3-θ1, A0B is the first distance, A0C is the second distance, A2B is the third distance, A2C is the fourth distance, BC is the distance between the first base station and the second base station, and A0A2 is the braking distance of the sightseeing car.

[0084] Furthermore, in this embodiment, the braking distance measured by the above method may still have a certain error due to the initial braking speed in some possible cases. In order to reduce the error of the measured braking distance, this embodiment may also include a process of correcting the measured braking distance. Fig. 9 As shown, it is a schematic diagram of the principle of correcting the braking distance. Accordingly, the specific correction method is as follows.

[0085] First, at the braking start time t0 of the sightseeing vehicle, the vehicle-mounted module 300 measures the current first acceleration value a1 of the sightseeing vehicle through the acceleration sensor, and calculates the current first speed V1 of the sightseeing vehicle.

[0086] Then, at the moment of full braking of the sightseeing vehicle, the vehicle-mounted module measures the current second acceleration value a of the sightseeing vehicle through the acceleration sensor. m and sends the speed data to the braking distance detection host 400, wherein the speed data includes the first acceleration value a1, the first speed V1, the second acceleration value a m , and the preset standard braking speed V0 of the sightseeing car.

[0087] Finally, the braking distance detection host 400 corrects the braking distance of the sightseeing vehicle according to the speed data.

[0088] The braking distance detection host corrects the braking distance of the sightseeing vehicle by the following formula:

[0089]

[0090] Wherein, S0 is the braking distance, S is the corrected braking distance; the braking start time is the time when the pedal tilt angle sensing module 200 detects that the tilt angle of the brake pedal is greater than the first tilt angle threshold, and the full braking time is the time when the pedal tilt angle sensing module 200 detects that the tilt angle of the brake pedal reaches the third tilt angle threshold. for Fig. 9 The ΔS in ΔS represents the error of the braking distance finally measured due to the difference between the braking speed of the stroller and the set standard braking speed V0.

[0091] Thus, in the embodiment of the present application, the braking distance S0 is adaptively corrected by using the distance ΔS passed from the speed V1 to V0 under the state of the maximum braking acceleration a m When starting to brake at the moment t0, the speed detection module measures the acceleration value a1 through the acceleration sensor therein, and integrates and calculates to obtain the speed V1. While at the moment t1 of full braking, the acceleration value a m is also obtained through the speed detection module. When V1 > V0, the braking distance S0 is correspondingly subtracted by ΔS to complete the correction. While when V1 < V0, the braking distance S0 is correspondingly added by ΔS to complete the correction.

[0092] Furthermore, in the actual on-site detection test, since the starting braking speed is self-controlled by the driver according to the vehicle speed displayed on the dashboard, therefore, in each test, there will inevitably be a deviation between the initial speed at the starting braking moment and the standard braking speed, and it is very difficult to ensure the complete consistency of the braking initial conditions. At the same time, the way that the driver slowly applies the braking pedal inclination will greatly increase the braking distance and cannot truly reflect the emergency braking performance of the vehicle.

[0093] According to the operating procedures, the driver must start emergency braking at the specified vehicle speed and complete the action of applying the maximum braking force to the braking pedal at the fastest speed. In order to eliminate the errors caused by human factors and ensure the validity of the test data, the present application also includes a determination process for whether the braking distance is valid. Specifically, the inclination angle of the braking pedal can be collected in real time through the pedal inclination sensing module 200, and the time T experienced by the inclination angle of the braking pedal increasing from the first inclination angle threshold to the third inclination angle threshold (the inclination angle of the pedal corresponding to the maximum braking force output), that is, the braking force establishment time T, is calculated, so as to determine whether the braking operation in the process of detecting the braking distance of the sightseeing vehicle is valid. When T is less than the set time threshold T0, it indicates that the test data of this braking test is valid, otherwise, the test data of this test is invalid. Specifically, the schematic diagram of the braking distance analysis and test validity check is as Fig.10 shown. Based on Fig.10 , the above process of validity check can be summarized as follows.

[0094] First, the inclination angle of the braking pedal is collected in real time through the inclination angle sensor of the pedal inclination sensing module 200, and the time experienced by the inclination angle of the braking pedal increasing from the first inclination angle threshold to the third inclination angle threshold is calculated as the braking force establishment time, and it is determined whether the braking operation in the process of detecting the braking distance of the sightseeing vehicle is valid according to the braking force establishment time; wherein, when the braking force establishment time is less than the set time threshold, the braking operation is determined to be valid, otherwise, the braking operation is determined to be invalid.

[0095] When the braking operation is determined to be effective, the braking distance detection host 400 can display the corrected braking distance; when the braking operation is determined to be invalid, a prompt message of invalid braking is issued to indicate that the current detection result is invalid.

[0096] Based on the above content, in this embodiment, the pedal inclination sensing module 200 may also include a three-axis acceleration sensor. Before starting the braking distance detection of the sightseeing vehicle, the method further includes an initialization step of the pedal inclination sensing module, which may be specifically completed by the pedal inclination sensing module 200, and an exemplary description is as follows.

[0097] First, the inspection personnel (which may be the driver) are prompted to perform an initialization operation on the brake pedal of the sightseeing vehicle, wherein the initialization operation includes pressing the brake pedal to the deepest position according to a set operation mode, and then gradually releasing the brake pedal until the brake pedal is released. For example, the driver may slowly press the brake pedal to the deepest position.

[0098] Then, during the above initialization operation, the pedal inclination sensing module 200 detects the acceleration values ​​in the X-axis and Z-axis directions through the three-axis acceleration sensor, calculates the real-time inclination of the brake pedal, and obtains the minimum inclination and maximum inclination of the sightseeing car brake pedal.

[0099] Finally, the first tilt angle threshold, the second tilt angle threshold, and the third tilt angle threshold are initialized according to the minimum tilt angle and the maximum tilt angle. For example, as an example, since the tilt angle of the brake pedal when the braking system starts braking should reach or exceed the minimum tilt angle, and the maximum braking output occurs at the moment of the maximum tilt angle, the minimum tilt angle can be used as the first tilt angle threshold, the maximum tilt angle can be used as the third tilt angle threshold, and the second tilt angle threshold can be set to 10% of the difference between the maximum tilt angle and the minimum tilt angle.

[0100] During the initialization process, the pedal inclination sensing module 200 can detect the acceleration values ​​in the X-axis and Z-axis directions through its own three-axis acceleration sensor to calculate the real-time inclination of the brake pedal. The inclination detection principle is as follows: Fig.11 shown.

[0101] Where β1=β2, β1 is the angle between the pedal inclination sensing module and the horizontal line, g X is the component of gravity acceleration g in the X-axis direction, that is, the X-axis acceleration measurement value of the three-axis acceleration sensor, g Z is the component of gravity acceleration g in the Z-axis direction, that is, the Z-axis acceleration measurement value on the three-axis acceleration sensor. The calculation formula of the brake pedal inclination angle β1 is as follows:

[0102]

[0103] After initialization, the pedal inclination sensing module 200 obtains the minimum inclination angle θ of the current sightseeing vehicle brake pedal. min and the maximum inclination angle θ max .

[0104] Furthermore, since there are changes in the acceleration value in the driving direction of the vehicle during the movement of the sightseeing car, which interferes with the inclination angle detection of the above-mentioned brake pedal, the embodiment of the present application can use the acceleration sensor of the on-board module 300 horizontally arranged on the sightseeing car to obtain the acceleration value a in the driving direction in real time, and automatically eliminate the acceleration interference in the driving direction through calculation, thereby realizing accurate measurement of the inclination angle of the brake pedal when the sightseeing car is in motion.

[0105] For example, considering the elimination of interference with the brake pedal inclination angle measurement, the method of the pedal inclination angle sensing module 200 sensing the inclination angle of the brake pedal may include:

[0106] The deceleration value of the sightseeing car is obtained through the acceleration sensor;

[0107] Acquiring a predetermined additional acceleration of the brake pedal generated in a vertical direction perpendicular to a brake pedal surface when the brake pedal is emergency braked;

[0108] The inclination angle of the brake pedal is calculated according to the deceleration value and the additional acceleration.

[0109] In detail, as an example, the schematic diagram of the principle of eliminating the vehicle motion interference during the brake pedal inclination angle detection process is as follows: Fig.12 shown.

[0110] Wherein, β1 is the angle between the pedal inclination sensing module 200 and the horizontal line, a is the acceleration measurement value in the X-axis direction obtained by the acceleration sensor, that is, the deceleration value of the sightseeing car, and a X is the component of the deceleration value a in the X-axis direction of the pedal inclination angle sensing module 200, a Z is the component of the deceleration value a in the Z-axis direction of the pedal inclination angle sensing module 200, a D To take into account the additional acceleration in the vertical direction of the brake pedal surface generated by the driver pressing the brake pedal during emergency braking, the direction and g Z The same, based on this, the acceleration value relationship is as follows:

[0111] Z a =g Z -a Z +a D ;

[0112] a D =Z amax -g Z_Init ;

[0113] X a =g X +a X .

[0114] Among them, Z a is the actual Z-axis acceleration measurement value of the pedal inclination angle sensing module 200, X a is the actual X-axis acceleration measurement value of the pedal inclination angle sensing module 200, Z amax is the pre-acquired acceleration value, g Z =g·cosβ2,g X =g·sinβ2,a Z =a·sinβ3,a X =a·cosβ3, and β1=β2=β3, so the final brake pedal inclination angle β1 can be calculated as follows:

[0115]

[0116] Among them, an emergency brake test action can be added based on the initialization operation when the vehicle is stationary, that is, the driver is asked to try to step on the brake pedal once in an emergency, and the maximum acceleration value of the sensor Z axis on the pedal surface is obtained as the Z amax , and decompose it to get the corresponding additional acceleration a D , where g Z_Init It represents the acceleration in the vertical direction of the pedal surface when the vehicle is stationary and the brake pedal is not pressed.

[0117] In summary, the sightseeing car braking distance detection system and method provided by the embodiment of the present application, combined with the detection of the brake pedal inclination angle, determines the distance data at the start and end of braking to realize the braking distance detection of the sightseeing car, which can effectively improve the detection accuracy. At the same time, the detection of the relevant moments such as the start and end of braking during the braking process adopts the method of placing the pedal inclination sensing module on the side of the brake pedal, which can reflect the entire process of stepping on the brake pedal, improve the detection accuracy of the braking distance, and greatly improve the safety during the braking distance detection and test process.

[0118] Furthermore, the embodiments of the present application combine the correction of braking distance, elimination of vehicle motion interference and other means to further improve the accuracy of the braking distance detected, eliminate the safety hazards of sightseeing vehicles, and improve the safety of sightseeing vehicles. In addition, the influence of factors such as shaking, side slip, skidding, and driving habits on the braking distance results can be further avoided during the braking process.

[0119] The above are only various implementations of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A sightseeing car braking distance detection system, characterized in that: The system includes a wireless distance measurement module, a pedal inclination sensing module, a vehicle-mounted module, and a braking distance detection host, wherein the wireless distance measurement module includes a first base station and a second base station which are arranged according to the braking position of the sightseeing vehicle during braking detection, the vehicle-mounted module is in communication connection with the first base station and the second base station, and the pedal inclination sensing module is fixedly installed on the side of the brake pedal of the sightseeing vehicle to detect the inclination of the brake pedal; Among them, the vehicle-mounted module is communicatively connected with the pedal inclination sensing module. When the pedal inclination sensing module senses that the inclination angle of the brake pedal reaches different inclination conditions at different times, the vehicle-mounted module is triggered to measure the distance between the sightseeing vehicle and the first base station and the second base station at each of the different times and send the measured distance to the braking distance detection host to detect the braking distance of the sightseeing vehicle.

2. The sightseeing vehicle braking distance detection system according to claim 1, characterized in that: The vehicle-mounted module includes a first positioning tag and a second positioning tag corresponding to the brake pedal of the sightseeing vehicle, and a speed detection unit, wherein the first positioning tag and the second positioning tag are respectively connected to the first base station and the second base station for communication. The vehicle-mounted module measures the distance between the sightseeing vehicle and the first base station through the first positioning tag and measures the distance between the sightseeing vehicle and the second base station through the second positioning tag at each of the different moments.

3. The sightseeing vehicle braking distance detection system according to claim 1, characterized in that: The pedal inclination sensing module includes a fixing device and an inclination sensor, and the inclination sensor is fixedly installed on the side of the brake pedal through the fixing device; wherein the fixing device includes a fixing plate and a Velcro assembly, the inclination sensor is fixed on the fixing plate, and the fixing plate is fixed to the side of the brake pedal through the Velcro assembly.

4. The sightseeing vehicle braking distance detection system according to claim 3, characterized in that: The Velcro assembly includes a first Velcro tape sleeved on the brake pedal along a first direction and a second Velcro tape sleeved on the brake pedal along a second direction, the fixing plate includes a first fixing portion and a second fixing portion, the first fixing portion extends along the first direction and is fixed to the brake pedal by the first Velcro tape, the second fixing portion extends along the second direction and is fixed to the brake pedal by the second Velcro tape, and the first direction intersects with the second direction.

5. The sightseeing vehicle braking distance detection system according to any one of claims 1 to 4, characterized in that: The pedal inclination angle sensing module is used to send first inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is greater than a first inclination angle threshold; The vehicle-mounted module is used for measuring and obtaining a first distance between the sightseeing vehicle and the first base station and a second distance between the sightseeing vehicle and the second base station upon receiving the first inclination angle data; The pedal inclination angle sensing module is further used to send second inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is restored to the second inclination angle threshold; The vehicle-mounted module is further used to measure a third distance between the current sightseeing vehicle and the first base station and a fourth distance between the sightseeing vehicle and the second base station when receiving the second inclination angle data, and send the measured distance data to a braking distance detection host, wherein the measured distance data includes the first distance, the second distance, the third distance and the fourth distance; The braking distance detection host is used to detect and obtain the braking distance of the sightseeing vehicle according to the distance data.

6. A method for detecting the braking distance of a sightseeing vehicle, characterized in that: The braking distance of a sightseeing vehicle is detected by using the sightseeing vehicle braking distance detection system according to any one of claims 1 to 5, and the method comprises: The pedal inclination angle sensing module sends first inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is greater than a first inclination angle threshold; When receiving the first inclination angle data, the vehicle-mounted module measures and obtains a first distance between the sightseeing vehicle and the first base station and a second distance between the sightseeing vehicle and the second base station; The pedal inclination angle sensing module sends the second inclination angle data to the vehicle-mounted module when detecting that the inclination angle of the brake pedal is restored to the second inclination angle threshold; When receiving the second inclination angle data, the vehicle-mounted module measures a third distance between the current sightseeing vehicle and the first base station and a fourth distance between the sightseeing vehicle and the second base station, and sends the measured distance data to a braking distance detection host, wherein the measured distance data includes the first distance, the second distance, the third distance and the fourth distance; The braking distance detection host detects and obtains the braking distance of the sightseeing vehicle according to the distance data.

7. The sightseeing vehicle braking distance detection method according to claim 6, characterized in that: The braking distance of the sightseeing car is calculated by the following formula: Among them, θ2=θ3-θ1, A0B is the first distance, A0C is the second distance, A2B is the third distance, A2C is the fourth distance, BC is the distance between the first base station and the second base station, and A0A2 is the braking distance of the sightseeing car.

8. The sightseeing vehicle braking distance detection method according to claim 6 or 7, characterized in that: The vehicle-mounted module further includes an acceleration sensor, and the method further includes: At the moment when the sightseeing vehicle starts braking, the vehicle-mounted module measures the current first acceleration value a1 of the sightseeing vehicle through the acceleration sensor, and calculates the current first speed V1 of the sightseeing vehicle. At the moment of full braking of the sightseeing vehicle, the vehicle-mounted module measures the current second acceleration value a of the sightseeing vehicle through the acceleration sensor. m and sending speed data to the braking distance detection host, wherein the speed data includes the first acceleration value a1, the first speed V1, the second acceleration value a m , and a preset standard braking speed V0 of the sightseeing vehicle; The braking distance detection host corrects the braking distance of the sightseeing vehicle according to the speed data; The braking distance detection host corrects the braking distance of the sightseeing vehicle by the following formula: Among them, S0 is the braking distance, S is the corrected braking distance; the starting braking moment is the moment when the pedal inclination sensing module detects that the inclination angle of the brake pedal is greater than the first inclination angle threshold, and the full braking moment is the moment when the pedal inclination sensing module detects that the inclination angle of the brake pedal reaches the third inclination angle threshold.

9. The sightseeing vehicle braking distance detection method according to claim 8, characterized in that: The pedal inclination angle sensing module includes a three-axis acceleration sensor; wherein, before starting the braking distance detection of the sightseeing vehicle, the method further includes an initialization step of the pedal inclination angle sensing module, and the initialization step includes: Prompting the inspector to perform an initialization operation on the brake pedal of the sightseeing vehicle, wherein the initialization operation includes pressing the brake pedal to the deepest position according to a set operation mode, and then gradually releasing the brake pedal to prevent the brake pedal from being stepped off; During the above initialization operation, the pedal inclination sensing module detects the acceleration values ​​in the X-axis and Z-axis directions through the three-axis acceleration sensor, calculates the real-time inclination of the brake pedal, and obtains the minimum inclination and maximum inclination of the brake pedal of the sightseeing car; The first tilt angle threshold, the second tilt angle threshold, and the third tilt angle threshold are initialized according to the minimum tilt angle and the maximum tilt angle.

10. The sightseeing vehicle braking distance detection method according to claim 9, characterized in that: The method further comprises: The inclination angle of the brake pedal is collected in real time by the inclination sensor of the pedal inclination sensing module, and the time taken for the inclination angle of the brake pedal to increase from the first inclination angle threshold to the third inclination angle threshold is calculated as the braking force establishment time, and whether the braking operation in the braking distance detection process of the sightseeing vehicle is effective is judged according to the braking force establishment time; wherein, when the braking force establishment time is less than the set time threshold, the braking operation is judged to be effective, otherwise, the braking operation is judged to be invalid; When it is determined that the braking operation is valid, the braking distance detection host displays the corrected braking distance; when it is determined that the braking operation is invalid, a prompt message of invalid braking is issued to prompt that the current detection result is invalid.

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