An unmanned mine dump truck front wheel turning angle calibration device and method

Abstract

The application discloses a kind of unmanned mine dump truck front wheel rotation angle calibration device and method, comprising: fixed part, for being connected with the shell of vehicle;Rotation angle sensor, fixed at the bottom of fixed part, for measuring the wheel rotation angle of vehicle, and realizing sensor calibration to vehicle by the rotation angle of measurement;Clamping part, for clamping the end surface of fixed wheel;Transmission mechanism, for connecting the measuring end of rotation angle sensor and clamping part, to pass the rotation angle information of wheel to rotation angle sensor, over vehicle steering sensor calibration, can obtain higher precision rotation angle parameter, improve navigation control precision, the angle of front wheel rotation can be directly measured, and vehicle-mounted steering sensor is calibrated with actual value;After a period of time, due to the problems such as deformation of connecting pin, position shift, increase of steering cylinder leakage, the rotation angle data deviation increases, the device in the application is used to calibrate vehicle steering sensor, and the navigation control precision can be improved.

Description

Technical Field

[0001] This invention relates to the field of mining dump truck technology, and more specifically, to a device and method for calibrating the front wheel angle of an unmanned mining dump truck. Background Technology

[0002] For unmanned mining dump trucks, the steering system adopts closed-loop control to ensure precise trajectory control. The main sensors currently used include: external cable sensors mounted on the steering cylinder, external magnetic extension sensors mounted on the steering cylinder, and internal magnetic extension sensors mounted on the steering cylinder. Magnetoresistive angle sensors and angle encoders are also installed on the kingpin.

[0003] Wheel angle data obtained by measuring the steering cylinder stroke is calculated based on sensor values ​​and steering mechanism dimensions. Manufacturing errors in the steering mechanism and wear of the rotating parts during use lead to increased clearance, causing discrepancies between the theoretical and actual wheel angles. Even using kingpin angle data, due to the kingpin's inclination and caster settings, results in a deviation between the kingpin angle and the wheel angle. In the unmanned driving control system of mining dump trucks, the accuracy of wheel angle measurement affects navigation control accuracy; inaccurate angle measurement can cause navigation errors or even collisions.

[0004] To address this issue, a device and method for calibrating the front wheel angle of an unmanned mining dump truck are proposed. Summary of the Invention

[0005] The present invention aims to provide a device and method for calibrating the front wheel angle of an unmanned mining dump truck, so as to solve or improve at least one of the above-mentioned technical problems.

[0006] In view of this, a first aspect of the present invention is to provide a front wheel steering angle calibration device for an unmanned mining dump truck.

[0007] A second aspect of the present invention is to provide a method for calibrating the front wheel steering angle of an unmanned mining dump truck.

[0008] A first aspect of the present invention provides a front wheel steering angle calibration device for an unmanned mining dump truck, comprising: a fixing part for connecting to the vehicle's housing; a steering angle sensor fixed to the bottom of the fixing part for measuring the wheel steering angle of the vehicle and calibrating the vehicle's sensor by measuring the steering angle; a clamping part for clamping and fixing the end face of the wheel; and a transmission mechanism for connecting the measuring end of the steering angle sensor and the clamping part to transmit the wheel steering angle information to the steering angle sensor.

[0009] The present invention provides a front wheel angle calibration device for an unmanned mining dump truck. After the unmanned mining dump truck is manufactured or modified, the vehicle steering sensor can be calibrated to obtain more accurate angle parameters, improve navigation control accuracy, and directly measure the angle of front wheel rotation, using the actual value to calibrate the vehicle steering sensor.

[0010] After a period of vehicle use, problems such as deformation of the connecting pin, displacement of position, and increased leakage of the steering cylinder can lead to increased deviation in steering angle data. Using the device in this invention to calibrate the vehicle steering sensor can improve navigation control accuracy.

[0011] In addition, the technical solutions provided by embodiments of the present invention may also have the following additional technical features:

[0012] In any of the above technical solutions, the fixing part includes: a fixing platform, the bottom of which is assembled with the corner sensor; and a magnet, disposed on the top of the fixing platform, for fixing the fixing platform to the housing.

[0013] In this technical solution, the corner sensor and the magnet are connected by a fixed platform, and the fixed platform is supported by a fixed platform, which can reduce the interference of the magnet on the measurement of the corner sensor. At the same time, the magnet can attract the iron alloy part of the vehicle body, so that the fixed platform can be fixed more easily.

[0014] At least one magnet is arranged along the circumference of the fixed platform, specifically four magnets are arranged at equal intervals along the circumference of the fixed platform, which can make the fixed platform be subjected to uniform force for more stable fixation.

[0015] In any of the above technical solutions, the transmission mechanism includes: a support rod, one end of which is connected to the measuring end; and a sleeve, the inner wall of which is slidably connected to the other end of the support rod, and the end of the sleeve away from the angle sensor is connected to the clamping part.

[0016] In this technical solution, the sliding connection of the support rod and sleeve is adopted, which allows the transmission mechanism to be adjusted in a telescopic manner. On the one hand, it can cope with different vehicle models and sizes, and on the other hand, it can extend and retract when the wheel moves in an arc, so that there is no interference between the rotation of the wheel and the single-axis rotation of the measuring end of the angle sensor.

[0017] In any of the above technical solutions, the side wall of the support rod is provided with a limiting rib along the axial direction of the support rod, and the inner wall of the sleeve is provided with a sliding groove that matches the limiting rib.

[0018] In this technical solution, a limiting rib is provided on the side wall of the support rod, and a sliding groove that matches the limiting rib is opened on the inner wall of the sleeve. The two grooves can slide relative to each other along the axis of the support rod, so that when the support rod slides inside the sleeve, there will be no relative rotation between it and the sleeve, thus avoiding interference with the angle sensor measurement.

[0019] In any of the above technical solutions, the clamping part includes: a clamping platform connected to the sleeve, the clamping platform having a through hole, the axis of the through hole being perpendicular to the axis of the measuring end; and a clamping assembly rotatably connected to the through hole, the clamping assembly being used to clamp and fix the end face of the wheel.

[0020] In this technical solution, a clamping platform is set up to connect with the sleeve, and both the clamping platform and the fixed platform need to be placed horizontally during installation to avoid inaccurate measurements caused by the tilt of the local structure of the device.

[0021] The clamping assembly is rotatably connected to the clamping platform through a through hole so that the horizontal setting of the clamping platform is not affected when clamping and fixing the wheel.

[0022] In any of the above technical solutions, the fixed platform and the clamping platform are respectively fixedly assembled with the level.

[0023] In this technical solution, a level is used to determine whether the lead screw, clamping platform, fixing platform, and angle sensor are adjusted to a horizontal state.

[0024] In any of the above technical solutions, a universal joint coupling is provided at the connection between the clamping platform and the sleeve, and at the connection between the support rod and the measuring end.

[0025] In this technical solution, the universal joint coupling is used as a rotating connection to act as a rotating joint when the wheel drives the clamping assembly and the clamping platform in an arc motion, so as to better adapt to the arc motion of the wheel and the circumferential rotation of the angle sensor.

[0026] In any of the above technical solutions, the clamping assembly includes: a lead screw, the middle part of which is rotatably connected to the sleeve, and the threads of the lead screw are symmetrically arranged along the middle part of the lead screw; two side arms, the top of the side arms having threaded holes adapted to the threads, and the side arms having extension plates arranged in a direction perpendicular to the axis of the lead screw; wherein, the opposing surfaces of the two extension plates are perpendicular to the axis of the lead screw.

[0027] In this technical solution, the middle part of the lead screw is rotatably connected to the sleeve, which allows the total weight of the lead screw and the side arms at both ends to be symmetrical about the middle part of the lead screw, reducing interference with the horizontal setting of the clamping platform during installation.

[0028] The opposing surfaces of the two extension plates are perpendicular to the axis of the lead screw. The opposing surfaces are used to clamp the end wall of the wheel for vehicle assembly and fixation. The perpendicularity along the axis of the lead screw allows the clamping platform to be horizontally positioned above the wheel after assembly.

[0029] In any of the above technical solutions, a handwheel is installed at one end of the lead screw; and / or a fixing hole communicating with the through hole is provided on the clamping platform, a fixing rod is screwed into the inner wall of the fixing hole, and a knob is installed at the end of the fixing rod away from the lead screw; and / or the center of gravity of the side arm is laterally aligned with the extension plate.

[0030] In this technical solution, a handwheel is installed on one end face of the lead screw, which allows for convenient manual operation of the lead screw and facilitates its use by operators.

[0031] By using a fixing rod screwed into a fixing hole, the fixing rod can move along the axis of the fixing hole to engage and release the lead screw, preventing the lead screw from rotating again after the two side arms clamp the wheel. A knob is also installed on the fixing rod to facilitate the operator to rotate the fixing rod.

[0032] By setting the center of gravity of the side arm so that it aligns laterally with the extension plate, the operator can avoid holding the side arm in position when operating the screw to rotate and drive the two side arms to open and close, thus facilitating the use of the device.

[0033] The second aspect of the present invention provides a method for calibrating the front wheel angle of an unmanned mining dump truck, comprising the following steps: S1, rotating the handwheel on the lead screw to move the two side arms in opposite directions. When the distance between the two side arms is greater than the wheel width, the device is placed at the center above the wheel, and the level is determined by observing the level gauge; S2, a strong magnet is attached to the underside of the housing above the wheel. After the platform is leveled, the nut on the screw is tightened. The angle sensor is determined to be level by observing the level gauge, and the transmission mechanism is approximately vertical, thus completing the fixing of one end of the device; S3, rotating the lead screw... The handwheel clamps the wheel between the two side arms, securing the other end of the device. A knob is used to drive the fixing rod to abut against the lead screw and connect the cable of the angle sensor. S4: The wheel is rotated to make it move in an arc on the horizontal plane, simultaneously driving the clamping part to move. Through the sliding fit of the support rod and the sleeve, and the rotation of the two hinge seats, the arc movement of the wheel is counteracted, and the angle rotation of the wheel is transmitted to the measuring end of the angle sensor through the clamping part and the transmission mechanism. S5: The sensor calibration of the vehicle is completed by using the value measured by the angle sensor. The method is implemented by the device as described in any one of the first aspects.

[0034] This invention provides a method for calibrating the front wheel angle of an unmanned mining dump truck. This method is implemented using a front wheel angle calibration device for an unmanned mining dump truck as described in the above-mentioned technical solution. Therefore, the method for calibrating the front wheel angle of an unmanned mining dump truck proposed in this invention possesses all the beneficial effects of the front wheel angle calibration device for an unmanned mining dump truck as described in the above-mentioned technical solution, which will not be elaborated further here.

[0035] The beneficial effects of this invention compared to the prior art are as follows:

[0036] After the unmanned mining dump truck is manufactured or modified, the vehicle steering sensor can be calibrated by the device in this invention to obtain more accurate angle parameters, improve navigation control accuracy, and directly measure the angle of front wheel rotation to calibrate the on-board steering sensor using the actual value.

[0037] After a period of vehicle use, problems such as deformation of the connecting pin, displacement of position, and increased leakage of the steering cylinder can lead to increased deviation in steering angle data. Using the device in this invention to calibrate the vehicle steering sensor can improve navigation control accuracy.

[0038] Additional aspects and advantages of embodiments of the invention will become apparent in the following description or may be learned by practice of embodiments of the invention. Attached Figure Description

[0039] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0040] Figure 1 This is a schematic diagram of the front wheel steering angle calibration device for the unmanned mining dump truck of the present invention;

[0041] Figure 2 This is a top view of the present invention.

[0042] in, Figure 1-2 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0043] 1. Magnet, 2. Angle sensor, 3. Transmission mechanism, 4. Knob, 5. Handwheel, 6. Lead screw, 7. Side arm, 8. Level. Detailed Implementation

[0044] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0045] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0046] Please see Figure 1-2 The first aspect of the present invention provides a front wheel angle calibration device for an unmanned mining dump truck, comprising: a fixing part for connecting to the vehicle's housing; an angle sensor 2 fixed to the bottom of the fixing part for measuring the wheel angle of the vehicle and calibrating the vehicle's sensor by measuring the angle; a clamping part for clamping and fixing the end face of the wheel; and a transmission mechanism 3 for connecting the measuring end of the angle sensor 2 and the clamping part to transmit the wheel angle information to the angle sensor 2.

[0047] The present invention provides a front wheel angle calibration device for an unmanned mining dump truck. After the unmanned mining dump truck is manufactured or modified, the vehicle steering sensor is calibrated by the device in the present invention, which can obtain more accurate angle parameters, improve navigation control accuracy, and directly measure the angle of front wheel rotation, and use the actual value to calibrate the vehicle steering sensor.

[0048] After a period of vehicle use, problems such as deformation of the connecting pin, displacement of position, and increased leakage of the steering cylinder can lead to increased deviation in steering angle data. Using the device in this invention to calibrate the vehicle steering sensor can improve navigation control accuracy.

[0049] In any of the above embodiments, as Figure 1-2 As shown, the fixing part includes: a fixing platform, the bottom of which is assembled with the angle sensor 2; and a magnet 1, at least one of which is arranged along the circumference of the fixing platform and is disposed on the top of the fixing platform, for fixing the fixing platform to the housing.

[0050] In this embodiment, the corner sensor 2 and the magnet 1 are connected by a fixed platform, and the fixed platform is supported by a fixed platform, which can reduce the measurement interference of the magnet 1 on the corner sensor 2. At the same time, the magnet 1 can attract the iron alloy part of the vehicle body, so that the fixed platform can be fixed more easily.

[0051] At least one magnet 1 is arranged along the circumference of the fixed platform. Specifically, four magnets 1 are arranged at equal intervals along the circumference of the fixed platform, which can make the fixed platform be subjected to uniform force so as to fix it more stably.

[0052] In any of the above embodiments, as Figure 1-2 As shown, a screw is installed on the end face of the magnet 1 that is in contact with the housing. The screw passes through the mounting hole of the housing and a nut is screwed onto the screw. The nut is used to cooperate with the magnet 1 to clamp the housing so that the fixed platform is assembled on the housing.

[0053] In this embodiment, when the housing has mounting holes, the screw can be inserted into the mounting holes, and the nuts and magnets 1 are used to clamp and fix it at both the inner and outer ends of the housing, which further improves the stability of the installation of the fixing platform.

[0054] In any of the above embodiments, as Figure 1-2 As shown, the transmission mechanism 3 includes: a support rod, one end of which is connected to the measuring end; and a sleeve, the inner wall of which is slidably connected to the other end of the support rod, and the end of the sleeve away from the angle sensor 2 is connected to the clamping part.

[0055] In this embodiment, the sliding connection of the support rod and the sleeve allows the transmission mechanism 3 to be adjusted in a telescopic manner. On the one hand, it can accommodate different vehicle models and sizes, and on the other hand, it can extend and retract when the wheel moves in an arc, so that there is no interference between the rotation of the wheel and the single-axis rotation of the measuring end of the angle sensor 2.

[0056] In any of the above embodiments, as Figure 1-2 As shown, the side wall of the support rod is provided with a limiting rib along the axial direction of the support rod, and the inner wall of the sleeve is provided with a sliding groove adapted to the limiting rib; wherein, at least one limiting rib is provided along the circumference of the support rod.

[0057] In this embodiment, a limiting rib is provided on the side wall of the support rod, and a sliding groove that cooperates with the limiting rib is opened on the inner wall of the sleeve. The two grooves can slide relative to each other along the axis of the support rod, so that when the support rod slides inside the sleeve, there will be no relative rotation between it and the sleeve, thus avoiding interference with the measurement of the angle sensor 2.

[0058] In any of the above embodiments, as Figure 1-2 As shown, the clamping part includes: a clamping platform connected to the sleeve, the clamping platform having a through hole, the axis of the through hole being perpendicular to the axis of the measuring end; and a clamping assembly rotatably connected to the through hole, the clamping assembly being used to clamp and fix the end face of the wheel.

[0059] In this embodiment, a clamping platform is provided for connecting to the sleeve, and both the clamping platform and the fixed platform need to be placed horizontally during installation to avoid inaccurate measurements caused by tilting of the local structure of the device.

[0060] The clamping assembly is rotatably connected to the clamping platform through a through hole so that the horizontal setting of the clamping platform is not affected when clamping and fixing the wheel.

[0061] In any of the above embodiments, as Figure 1-2 As shown, universal joint couplings are installed at the connection between the clamping platform and the sleeve, and at the connection between the support rod and the measuring end.

[0062] In this embodiment, the universal joint coupling is used as a rotating connection to act as a rotating joint when the wheel drives the clamping assembly and the clamping platform in an arc motion. This allows for better adaptation between the arc motion of the wheel and the circumferential rotation of the angle sensor 2. Only the angular force of the wheel is transmitted to the measuring end of the angle sensor 2, which then rotates to complete the measurement, thus avoiding interference from the arc motion of the wheel that would prevent it from moving.

[0063] In any of the above embodiments, as Figure 1-2 As shown, the clamping assembly includes: a lead screw 6, the middle part of which is rotatably connected to a sleeve, and the threads of the lead screw 6 are symmetrically arranged along the middle part of the lead screw 6; two side arms 7, the top of the side arms 7 is provided with threaded holes that are adapted to the threads, and the side arms 7 are provided with extension plates in a direction perpendicular to the axis of the lead screw 6; wherein, the opposing surfaces of the two extension plates are uniformly perpendicular to the axis of the lead screw 6.

[0064] In this embodiment, the middle part of the lead screw 6 is rotatably connected to the sleeve, which enables the total weight of the lead screw 6 and the side arms 7 at both ends to be symmetrical about the middle part of the lead screw 6, reducing interference with the horizontal setting of the clamping platform during installation.

[0065] The opposing surfaces of the two extension plates are perpendicular to the axis of the lead screw 6. The opposing surfaces are used for clamping the end wall of the wheel to fix the vehicle in place. The perpendicularity along the axis of the lead screw 6 allows the clamping platform to be horizontally positioned above the wheel after assembly.

[0066] In any of the above embodiments, as Figure 1-2 As shown, a handwheel 5 is installed on one end face of the lead screw 6; and / or a fixing hole communicating with the through hole is opened on the clamping platform, a fixing rod is screwed into the inner wall of the fixing hole, and a knob 4 is installed on the end of the fixing rod away from the lead screw 6; and / or the center of gravity of the side arm 7 corresponds to the extension plate laterally.

[0067] In this embodiment, a handwheel 5 is installed on one end face of the lead screw 6, which allows for convenient manual rotation of the lead screw 6 and facilitates its use by operators.

[0068] By screwing a fixing rod into a fixing hole, the fixing rod can move along the axis of the fixing hole to engage and release the lead screw 6, preventing the lead screw 6 from rotating again after the two side arms 7 clamp the wheel. A knob 4 is also installed on the fixing rod to facilitate the operator to rotate the fixing rod.

[0069] By setting the center of gravity of the side arm 7 so that it corresponds laterally to the extension plate, it is possible to avoid the operator holding the side arm 7 to maintain the position when operating the screw 6 to rotate and drive the two side arms 7 to open and close, thus facilitating the use of the device.

[0070] The second aspect of the present invention provides a method for calibrating the front wheel angle of an unmanned mining dump truck, comprising the following steps: S1, rotating the handwheel 5 on the lead screw 6 to move the two side arms 7 in opposite directions; when the distance between the two side arms 7 is greater than the wheel width, placing the device at the center above the wheel, and adjusting the lead screw 6 to be horizontal according to the level 8; S2, attaching the strong magnet 1 to the platform above the wheel, adjusting the angle sensor 2 to be horizontal according to the level 8, and tightening the nut on the screw after fixing the platform horizontally to complete the fixing of one end of the device; S3, rotating the handwheel 5 on the lead screw 6 to move the two side arms 7 in opposite directions. Clamp the wheel to secure the other end of the device. Use knob 4 to drive the fixing rod to abut against the lead screw 6 and connect the cable of the angle sensor 2. S4, rotate the wheel to make it move in an arc on the horizontal plane, and simultaneously drive the clamping part to move. Through the sliding cooperation of the support rod and the sleeve, and the rotation of the two hinge seats, the arc movement of the wheel is counteracted, and the angle rotation of the wheel is transmitted to the rotating shaft of the angle sensor 2 through the clamping part and the transmission mechanism 3. S5, the value measured by the angle sensor 2 is corrected for the kingpin inclination and backward tilting to become the actual wheel angle, which is used to calibrate the vehicle's original sensor. The vehicle's sensor calibration is completed; wherein, the method is implemented by the device of any embodiment of the first aspect.

[0071] This invention provides a method for calibrating the front wheel angle of an unmanned mining dump truck. This method is implemented using a front wheel angle calibration device for an unmanned mining dump truck as described in the above embodiments. Therefore, the method for calibrating the front wheel angle of an unmanned mining dump truck proposed in this invention possesses all the beneficial effects of the front wheel angle calibration device for an unmanned mining dump truck as described in the above embodiments, and will not be elaborated further here.

[0072] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0073] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A device for calibrating the front wheel angle of an unmanned mining dump truck, characterized in that, include: A mounting part, used to connect to the vehicle body; Angle sensor (2) is fixed to the bottom of the fixing part and is used to measure the wheel angle of the vehicle and to calibrate the vehicle's sensors by measuring the angle. The clamping part is used to clamp and fix the end face of the wheel; Transmission mechanism (3) is used to connect the measuring end of the angle sensor (2) and the clamping part to transmit the angle information of the wheel to the angle sensor (2). A level (8) is installed on the fixed part and the clamping part respectively to determine whether the fixed part and the angle sensor (2) are adjusted to a horizontal state; The fixing part includes: A fixed platform, the bottom of which is assembled with the angle sensor (2); A magnet (1) is disposed on the top of the fixed platform for fixing the fixed platform to the housing; the magnet is attracted to the underside of the housing above the wheel; The transmission mechanism (3) includes: A support rod, one end of which is connected to the measuring end; A sleeve, the inner wall of which is slidably connected to the other end of the support rod, and the end of the sleeve away from the angle sensor (2) is connected to the clamping part; The clamping part includes: A clamping platform is connected to the sleeve, and the clamping platform has a through hole, the axis of which is perpendicular to the axis of the measuring end; A clamping assembly, which is rotatably connected to the through hole, is used to clamp and fix the end face of the wheel; A universal joint coupling is provided at the connection between the clamping platform and the sleeve, and at the connection between the support rod and the measuring end; The clamping assembly includes: A lead screw (6) is rotatably connected to the sleeve at its middle part, and the threads of the lead screw (6) are symmetrically arranged along the middle part of the lead screw (6); Two side arms (7), the top of the side arms (7) is provided with threaded holes that are compatible with the thread, and the side arms (7) are provided with extension plates in a direction perpendicular to the axis of the lead screw (6); The opposing surfaces of the two extension plates are perpendicular to the axis of the lead screw (6).

2. The unmanned mining dump truck front wheel steering angle calibration device according to claim 1, characterized in that, The side wall of the support rod is provided with a limiting rib along the axial direction of the support rod, and the inner wall of the sleeve is provided with a sliding groove that matches the limiting rib.

3. The unmanned mining dump truck front wheel steering angle calibration device according to claim 2, characterized in that, The fixed platform and the clamping platform are respectively fixedly assembled with the level (8).

4. The unmanned mining dump truck front wheel steering angle calibration device according to claim 3, characterized in that, A handwheel (5) is installed at one end of the lead screw (6); and / or The clamping platform has a fixing hole communicating with the through hole. A fixing rod is screwed to the inner wall of the fixing hole, and a knob (4) is installed on the end of the fixing rod away from the lead screw (6); and / or The center of gravity of the side arm (7) is laterally aligned with the extension plate.

5. A method for calibrating the front wheel steering angle of an unmanned mining dump truck, characterized in that, Includes the following steps: S1, rotate the handwheel (5) on the screw (6) to make the two side arms (7) move in opposite directions. When the distance between the two side arms (7) is greater than the width of the wheel, place the device at the center above the wheel and determine the level of the adjusting screw (6) by observing the level (8). S2, attract the strong magnet (1) to the underside of the housing above the wheel, tighten the nut on the screw after the fixed platform is level, and determine the level of the angle sensor (2) by observing the level (8). The transmission mechanism (3) is roughly in a vertical state, and one end of the device is fixed. S3, rotate the handwheel (5) on the lead screw (6) to clamp the wheel with the two side arms (7), and fix the other end of the device. Use the knob (4) to drive the fixing rod to abut against the lead screw (6) and connect the cable of the angle sensor. S4, rotate the wheel to make it move in an arc on the horizontal plane, and drive the clamping part to move in sync. Through the sliding cooperation of the support rod and the sleeve, as well as the rotation of the two hinge seats, the arc movement of the wheel is offset, and the angle rotation of the wheel is transmitted to the measuring end of the angle sensor (2) through the clamping part and the transmission mechanism. S5, the sensor calibration of the vehicle is completed by measuring the value of the angle sensor (2); The method is implemented by the apparatus as described in any one of claims 1-4.

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