Tricycle torque determination method, device, controller, vehicle, medium and product

Abstract

This application provides a method, device, controller, vehicle, medium, and product for determining the torque of a three-wheeled vehicle. In this method, during the steering process, the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road surface adhesion coefficient are acquired. Then, based on the target steering angle, actual steering angle, and actual wheel angular velocity, the steering torque difference is determined. Based on the target vehicle speed and road surface adhesion coefficient, the longitudinal drive torque is determined. Finally, based on the target steering angle, the steering torque difference, and the longitudinal drive torque, the torque of the left and right rear wheels is determined. This solution reduces the difference between the actual and target steering angles by adjusting the left and right rear wheel torques in real time during the steering process based on the actual and target steering angles.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a method, device, controller, vehicle, medium, and product for determining the torque of a three-wheeled vehicle. Background Technology

[0002] Unmanned tricycles have applications in various fields, such as cleaning and delivery. They are divided into two types: those with active front-wheel steering and those with passive front-wheel steering.

[0003] In the prior art, for vehicles with front-wheel driven steering, the two rear wheels are driven independently, and the front wheels are driven swivel wheels. The torque of the two rear wheels can be determined according to the target steering angle and the target vehicle speed, and steering is achieved by the difference in torque between the two rear wheels.

[0004] However, in existing technologies, the torque of the two rear wheels remains constant during steering, which leads to a large difference between the actual steering angle and the target steering angle during steering. Summary of the Invention

[0005] The method, device, controller, vehicle, medium, and product for determining the torque of a tricycle provided in this application are intended to solve the problem in the prior art where the torque of the two rear wheels of a tricycle remains unchanged during the turning process, resulting in a large difference between the actual turning angle and the target turning angle.

[0006] In a first aspect, embodiments of this application provide a method for determining the torque of a three-wheeled vehicle, applied to a controller in a three-wheeled vehicle, the method comprising:

[0007] During the steering process, the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road adhesion coefficient are obtained.

[0008] The steering torque difference is determined based on the target steering angle, the actual steering angle, and the actual wheel angular velocity.

[0009] The longitudinal drive torque is determined based on the target vehicle speed and the road surface adhesion coefficient.

[0010] The left rear wheel torque and right rear wheel torque are determined based on the target steering angle, the steering torque difference, and the longitudinal drive torque.

[0011] In one possible implementation, determining the steering torque difference based on the target steering angle, the actual steering angle, and the actual wheel rotation angular velocity includes:

[0012] Based on the target steering angle, the actual steering angle, and the actual wheel angular velocity, determine the target angle error and the target wheel angular velocity error;

[0013] The comprehensive error is calculated based on the target angle error, the target wheel rotation angle and angular velocity error, the preset angle weight, and the preset angular velocity weight.

[0014] The steering torque difference is calculated based on the comprehensive error and the proportional-integral-derivative PID algorithm.

[0015] In one possible implementation, determining the target angle error and the target wheel rotation angle error based on the target steering angle, the actual steering angle, and the actual wheel rotation angle angular velocity includes:

[0016] The difference between the target steering angle and the actual steering angle is taken as the target angle error;

[0017] Based on the preset correspondence between angle error and wheel rotation angle angular velocity, the target wheel rotation angle angular velocity corresponding to the target angle error is determined, wherein the angle error and wheel rotation angle angular velocity are proportional in the correspondence between angle error and wheel rotation angle angular velocity;

[0018] The difference between the target wheel's angular velocity and the actual wheel's angular velocity is taken as the target wheel's angular velocity error.

[0019] In one possible implementation, determining the left rear wheel torque and right rear wheel torque based on the target steering angle, the steering torque difference, and the longitudinal drive torque includes:

[0020] If the sign of the target steering angle indicates a left turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque.

[0021] If the sign of the target steering angle indicates a right turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque, and half of the sum of the longitudinal drive torque and the steering torque difference is taken as the left rear wheel torque.

[0022] In one possible implementation, obtaining the true steering angle includes:

[0023] Calculate the current vehicle speed based on the obtained left and right rear wheel speeds;

[0024] The actual steering angle is calculated based on the current vehicle speed, the obtained yaw rate, and the wheelbase.

[0025] In one possible implementation, the method further includes:

[0026] Obtain the left rear wheel speed, the right rear wheel speed, the first left rear wheel torque threshold, and the first right rear wheel torque threshold;

[0027] Based on the preset correspondence between steering angle, wheel speed and torque threshold, a second left rear wheel torque threshold corresponding to the actual steering angle and the left rear wheel speed, and a second right rear wheel torque threshold corresponding to the actual steering angle and the right rear wheel speed are determined.

[0028] The minimum value among the left rear wheel torque, the first left rear wheel torque threshold, and the second left rear wheel torque threshold is used as the updated left rear wheel torque;

[0029] The minimum value among the right rear wheel torque, the first right rear wheel torque threshold, and the second right rear wheel torque threshold is used as the updated right rear wheel torque.

[0030] Secondly, embodiments of this application provide a three-wheeled vehicle torque determining device, comprising:

[0031] The acquisition module is used to acquire the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road adhesion coefficient during the steering process.

[0032] The processing module is used to determine the steering torque difference based on the target steering angle, the actual steering angle, and the actual wheel rotation angular velocity;

[0033] The processing module is also used to determine the longitudinal driving torque based on the target vehicle speed and the road surface adhesion coefficient;

[0034] The torque determination module is used to determine the left rear wheel torque and the right rear wheel torque based on the target steering angle, the steering torque difference, and the longitudinal drive torque.

[0035] Thirdly, embodiments of this application provide a controller, including:

[0036] Processor, memory, communication interface;

[0037] The memory is used to store the executable instructions of the processor;

[0038] The processor is configured to execute the tricycle torque determination method according to any one of the first aspects by executing the executable instructions.

[0039] Fourthly, embodiments of this application provide a three-wheeled vehicle, including a controller;

[0040] The controller is used to execute the tricycle torque determination method described in any of the first aspects above.

[0041] Fifthly, embodiments of this application provide a readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method for determining the torque of a three-wheeled vehicle as described in any of the first aspects.

[0042] Sixthly, embodiments of this application provide a computer program product, including a computer program, which, when executed by a processor, is used to implement the method for determining the torque of a three-wheeled vehicle as described in any of the first aspects.

[0043] The three-wheeled vehicle torque determination method, device, controller, vehicle, medium, and product provided in this application's embodiments acquire the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road surface adhesion coefficient during the steering process; then, based on the target steering angle, actual steering angle, and actual wheel angular velocity, determine the steering torque difference; based on the target vehicle speed and road surface adhesion coefficient, determine the longitudinal driving torque; and finally, based on the target steering angle, steering torque difference, and longitudinal driving torque, determine the left and right rear wheel torques. This solution reduces the difference between the actual and target steering angles by adjusting the left and right rear wheel torques in real time based on the actual and target steering angles during the steering process. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0045] Figure 1 A flowchart illustrating an embodiment of the method for determining the torque of a three-wheeled vehicle provided in this application;

[0046] Figure 2 A schematic diagram of the steering angle provided in this application;

[0047] Figure 3 A flowchart illustrating Embodiment 2 of the method for determining the torque of a three-wheeled vehicle provided in this application;

[0048] Figure 4 A schematic diagram of the structure of an embodiment of the tricycle torque determining device provided in this application;

[0049] Figure 5 This is a schematic diagram of the structure of a controller provided in this application.

[0050] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0051] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0052] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0053] Unmanned tricycles have applications in various fields, such as cleaning and delivery. They are divided into two types: those with active front-wheel steering and those with passive front-wheel steering.

[0054] In existing technologies, for vehicles with front-wheel driven steering, the two rear wheels are driven independently, while the front wheels are driven swivel wheels. The torque of the two rear wheels can be determined based on the target steering angle and target vehicle speed, and steering is achieved by varying the torque of the two rear wheels. However, the torque of the two rear wheels remains constant during steering, and uneven road surfaces can lead to a significant difference between the actual steering angle and the target steering angle.

[0055] To address the problems existing in the prior art, the inventors, during their research on methods for determining the torque of a tricycle, discovered that the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road surface adhesion coefficient can be obtained during the steering process. Then, based on the target steering angle, actual steering angle, and actual wheel angular velocity, the steering torque difference is determined; based on the target vehicle speed and road surface adhesion coefficient, the longitudinal driving torque is determined; finally, based on the target steering angle, steering torque difference, and longitudinal driving torque, the torque of the left and right rear wheels is determined. By adjusting the torque of the left and right rear wheels in real time based on the actual and target steering angles during the steering process, the difference between the actual and target steering angles is reduced. Based on the above inventive concept, the tricycle torque determination scheme of this application was designed.

[0056] The following provides an example illustrating the application scenarios of the method for determining the torque of a three-wheeled vehicle provided in this application.

[0057] For example, in this application scenario, the tricycle is an unmanned tricycle used for sweeping. The front wheel of the tricycle is a driven swivel wheel, and the left and right rear wheels are independently driven drive wheels. The controller in the tricycle can determine whether to turn based on the set route and the current position; or it can determine whether to turn based on the current environment. When turning is required, the target turning angle and target speed can be determined.

[0058] During the steering process, the controller also needs to obtain the actual steering angle, the actual wheel angular velocity, and the road surface adhesion coefficient.

[0059] Then, based on the target steering angle, the actual steering angle, and the actual wheel rotation angle angular velocity, the steering torque difference is determined; based on the target vehicle speed and the road surface adhesion coefficient, the longitudinal drive torque is determined.

[0060] The controller determines the torque of the left and right rear wheels based on the target steering angle, the steering torque difference, and the longitudinal drive torque. It then controls the left rear wheel to roll based on the left rear wheel torque and the right rear wheel to roll based on the right rear wheel torque, thus achieving steering and ensuring that the actual steering angle closely approximates the target steering angle.

[0061] It should be noted that the above scenario is only an example of an application scenario provided by the embodiments of this application. The embodiments of this application do not limit the actual form of the various devices included in the scenario, nor do they limit the interaction method between devices. In the specific application of the solution, it can be set according to actual needs.

[0062] The technical solution of this application will now be described in detail through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0063] Figure 1 This is a flowchart illustrating an embodiment of the three-wheeled vehicle torque determination method provided in this application. This embodiment describes how the controller determines the torque of the left and right rear wheels during steering based on the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road surface adhesion coefficient. The method in this embodiment can be implemented through software, hardware, or a combination of both. Figure 1 As shown, the method for determining the torque of this tricycle specifically includes the following steps:

[0064] S101: During the steering process, obtain the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road adhesion coefficient.

[0065] In this step, in order to reduce the difference between the actual steering angle and the target steering angle during the steering process, it is necessary to obtain the actual steering angle, the target steering angle, the actual wheel angular velocity, the target vehicle speed, and the road adhesion coefficient.

[0066] It should be noted that both the actual steering angle and the target steering angle have signs. A positive sign indicates a left turn, and a negative sign indicates a right turn. Alternatively, a positive sign indicates a right turn, and a negative sign indicates a left turn.

[0067] It should be noted that an Inertial Measurement Unit (IMU) can be installed on the front wheel to obtain the actual wheel rotation angle and angular velocity.

[0068] One method for obtaining the road surface adhesion coefficient is as follows: the controller stores the correspondence between location and road surface adhesion coefficient, and determines the corresponding road surface adhesion coefficient based on the current location. Another method is to install a camera on the road surface in the tricycle, and the controller inputs the road surface image captured by the camera into a trained machine learning model to obtain the road surface adhesion coefficient. This application does not limit the method for obtaining the road surface adhesion coefficient; it can be determined according to the actual situation.

[0069] One way to obtain the true steering angle is to install an angle sensor on the front wheel and obtain the true steering angle through the angle sensor.

[0070] Another method for obtaining the true steering angle is to first calculate the current vehicle speed based on the obtained left and right rear wheel speeds. Then, based on the current vehicle speed, the obtained yaw rate, and wheelbase, calculate the true steering angle.

[0071] Both rear wheels are equipped with wheel speed sensors, allowing the acquisition of the left and right rear wheel speeds. An IMU (Insulated Unit) is installed in the vehicle to acquire the yaw rate. The wheelbase is the distance between the center point of the line connecting the two rear wheels and the front wheels. Half the sum of the left and right rear wheel speeds is taken as the current vehicle speed. Then, according to the formula... Calculate the actual steering angle.

[0072] in, The value represents the actual steering angle, L represents the wheelbase, w represents the yaw rate, and v represents the current vehicle speed.

[0073] During a turn, the vehicle rotates around the steering center point, which is the intersection of the perpendicular lines pointing to the three wheels. Since the two rear wheels do not turn, the steering center point lies on the line connecting the two rear wheels. The distance between the steering center point and the center point of the line connecting the two rear wheels is R. The velocity at the center point of the line connecting the two rear wheels is the current vehicle speed v. According to geometric relationships, the angle between the first and second straight lines is equal to the actual steering angle. The first straight line is the line connecting the front wheel and the steering center point, and the second straight line is the line connecting the two rear wheels. That is .

[0074] For example, Figure 2 The steering angle diagram provided in this application is as follows: Figure 2 As shown, the angle between the first and second lines is equal to the actual turning angle. .

[0075] It should be noted that when the speeds of the left and right rear wheels are positive, it indicates that the wheels are rolling forward; when the speeds of the left and right rear wheels are negative, it indicates that the wheels are rolling backward.

[0076] S102: Determine the steering torque difference based on the target steering angle, the actual steering angle, and the actual wheel rotation angular velocity.

[0077] In this step, after the controller obtains the actual steering angle, the target steering angle, and the actual wheel angular velocity, in order to adjust the torque of the left rear wheel and the right rear wheel so that the actual steering angle is closer to the target steering angle and closer to it quickly, the steering torque difference can be determined based on the target steering angle, the actual steering angle, and the actual wheel angular velocity.

[0078] Specifically, the target angle error and the target wheel rotation angle error are determined based on the target steering angle, the actual steering angle, and the actual wheel rotation angle angular velocity.

[0079] In other words, the difference between the target turning angle and the actual turning angle is taken as the target angle error.

[0080] Based on the preset correspondence between angle error and wheel rotation angular velocity, the target wheel rotation angular velocity corresponding to the target angle error is determined. The difference between the target wheel rotation angular velocity and the actual wheel rotation angular velocity is taken as the target wheel rotation angular velocity error.

[0081] It should be noted that in the relationship between angular error and wheel rotation angular velocity, the angular error is directly proportional to the wheel rotation angular velocity. The larger the angular error, the faster it needs to be reduced, and the greater the wheel rotation angular velocity should be. Therefore, the angular error is directly proportional to the wheel rotation angular velocity.

[0082] For example, an angle error of 5 degrees corresponds to a wheel rotation angular velocity of 10 degrees per second; an angle error of 10 degrees corresponds to a wheel rotation angular velocity of 20 degrees per second; and an angle error of 15 degrees corresponds to a wheel rotation angular velocity of 30 degrees per second. This application does not limit the correspondence between angle error and wheel rotation angular velocity; it can be determined according to actual circumstances.

[0083] After obtaining the target angle error and the target wheel rotation angle and angular velocity error, the controller calculates the comprehensive error based on the target angle error, the target wheel rotation angle and angular velocity error, the preset angle weight, and the preset angular velocity weight.

[0084] That is, the target angle error and the target wheel rotation angle and angular velocity error are normalized to obtain the angle normalization error and the angular velocity normalization error; the product of the angle normalization error and the preset angle weight is taken as the first product; the product of the angular velocity normalization error and the preset angular velocity weight is taken as the second product; the sum of the first product and the second product is taken as the comprehensive error.

[0085] It should be noted that the sum of the preset angle weight and the preset angular velocity weight is 1. The preset angle weight can be 0.9, 0.8, 0.7, etc., and the preset angular velocity weight can be 0.1, 0.2, 0.3, etc. The embodiments of this application do not limit the preset angle weight and the preset angular velocity weight, which can be determined according to the actual situation.

[0086] Then, based on the comprehensive error and the Proportional-Integral-Derivative (PID) algorithm, the steering torque difference is calculated. In other words, the PID algorithm is used to process the comprehensive error to obtain the steering torque difference. The steering torque difference is the torque difference required between the two rear wheels to achieve the change from the actual steering angle to the target steering angle.

[0087] The comprehensive error is calculated from the target angle error and the target wheel rotation angle angular velocity error. This can reduce the difference between the actual steering angle and the target steering angle, and also improve the efficiency of converting the actual steering angle into the target steering angle.

[0088] S103: Determine the longitudinal drive torque based on the target vehicle speed and road surface adhesion coefficient.

[0089] In this step, after the controller obtains the target vehicle speed and the road surface adhesion coefficient, in order to enable the vehicle to reach the target speed when turning, it is necessary to determine the longitudinal drive torque based on the target vehicle speed and the road surface adhesion coefficient.

[0090] There is a corresponding relationship between vehicle speed, road surface adhesion coefficient and longitudinal driving torque, so the corresponding longitudinal driving torque can be determined based on the target vehicle speed and road surface adhesion coefficient.

[0091] The longitudinal driving torque is proportional to the vehicle speed and the road surface adhesion coefficient.

[0092] It should be noted that the execution order of steps S102 and S103 can be as follows: step S102 can be executed first, followed by step S103; step S103 can be executed first, followed by step S102; or steps S102 and S103 can be executed simultaneously. This embodiment does not limit the execution order of steps S102 and S103, and it can be determined according to the actual situation.

[0093] S104: Determine the left rear wheel torque and right rear wheel torque based on the target steering angle, steering torque difference, and longitudinal drive torque.

[0094] In this step, after obtaining the steering torque difference and longitudinal drive torque, the controller determines the left and right rear wheel torques based on the target steering angle. Subsequently, the left rear wheel is controlled to roll based on the left rear wheel torque, and the right rear wheel is controlled to roll based on the right rear wheel torque, so that the steering speed is the target steering speed and the actual steering angle is close to the target steering angle.

[0095] Specifically, if the sign of the target steering angle indicates a left turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque.

[0096] If the target steering angle sign indicates a right turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque.

[0097] The sum of the torque of the left rear wheel and the torque of the right rear wheel is the longitudinal drive torque, achieving a steering speed that is close to the target steering speed. The sign of the target steering angle indicates a left turn, and the difference between the torque of the right rear wheel and the torque of the left rear wheel is the steering torque difference; the sign of the target steering angle indicates a right turn, and the difference between the torque of the left rear wheel and the torque of the right rear wheel is the steering torque difference, achieving a true steering angle that is close to the target steering angle.

[0098] The three-wheeled vehicle torque determination method provided in this embodiment acquires the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road surface adhesion coefficient during the steering process. Then, based on the target steering angle, actual steering angle, and actual wheel angular velocity, the steering torque difference is determined. Based on the target vehicle speed and road surface adhesion coefficient, the longitudinal drive torque is determined. Finally, based on the target steering angle, steering torque difference, and longitudinal drive torque, the left and right rear wheel torques are determined. This solution reduces the difference between the actual and target steering angles by adjusting the left and right rear wheel torques in real time based on the actual and target steering angles during the steering process.

[0099] In addition, by adjusting the torque of the two rear wheels according to the actual steering angle during the steering process, the torque adjustment will affect the actual steering angle, and a new actual steering angle will be obtained again to adjust the torque of the two rear wheels, thus achieving closed-loop control.

[0100] Figure 3 This is a flowchart illustrating a second embodiment of the method for determining the torque of a three-wheeled vehicle provided in this application. Based on the above embodiments, this application describes the situation where the controller updates the torque of the left and right rear wheels. Figure 3 As shown, the method for determining the torque of this tricycle specifically includes the following steps:

[0101] S301: Obtain the left rear wheel speed, right rear wheel speed, first left rear wheel torque threshold, and first right rear wheel torque threshold.

[0102] In this step, the controller obtains the torque of the left and right rear wheels. To prevent the vehicle from becoming dangerous due to excessive torque, and to ensure that the torque does not exceed the maximum torque that the wheel motors can provide, the left and right rear wheel torques need to be updated. This requires obtaining the left rear wheel speed, right rear wheel speed, a first left rear wheel torque threshold, and a first right rear wheel torque threshold.

[0103] It should be noted that the first left rear wheel torque threshold is the maximum torque that the motor of the left rear wheel can provide, and the first right rear wheel torque threshold is the maximum torque that the motor of the right rear wheel can provide. The first left rear wheel torque threshold and the first right rear wheel torque threshold can be 30 Nm, 50 Nm, 200 Nm, 500 Nm, etc. The embodiments of this application do not limit the first left rear wheel torque threshold and the first right rear wheel torque threshold, and can be determined according to the actual situation.

[0104] S302: Based on the preset correspondence between steering angle, wheel speed and torque threshold, determine the second left rear wheel torque threshold corresponding to the actual steering angle and the left rear wheel speed, and the second right rear wheel torque threshold corresponding to the actual steering angle and the right rear wheel speed.

[0105] In this step, after the controller obtains the left rear wheel speed and the right rear wheel speed, it determines the second left rear wheel torque threshold corresponding to the actual steering angle and the left rear wheel speed, and the second right rear wheel torque threshold corresponding to the actual steering angle and the right rear wheel speed, based on the preset correspondence between steering angle, wheel speed and torque threshold.

[0106] In the relationship between steering angle, wheel speed and torque threshold, the torque threshold is inversely proportional to the steering angle, and the wheel speed is inversely proportional to the torque threshold.

[0107] The second left rear wheel torque threshold and the second right rear wheel torque threshold are the maximum torques that ensure the vehicle will not pose a danger.

[0108] S303: Use the minimum value among the left rear wheel torque, the first left rear wheel torque threshold, and the second left rear wheel torque threshold as the updated left rear wheel torque.

[0109] In this step, after the controller obtains the first left rear wheel torque threshold and the second left rear wheel torque threshold, it takes the minimum value among the left rear wheel torque, the first left rear wheel torque threshold, and the second left rear wheel torque threshold as the updated left rear wheel torque.

[0110] S304: The minimum value among the right rear wheel torque, the first right rear wheel torque threshold, and the second right rear wheel torque threshold is used as the updated right rear wheel torque.

[0111] In this step, after the controller obtains the first right rear wheel torque threshold and the second right rear wheel torque threshold, it takes the minimum value among the right rear wheel torque, the first right rear wheel torque threshold, and the second right rear wheel torque threshold as the updated right rear wheel torque.

[0112] The method for determining the torque of a three-wheeled vehicle provided in this embodiment updates the torque of the left and right rear wheels by using a first left rear wheel torque threshold, a first right rear wheel torque threshold, a second left rear wheel torque threshold, and a second right rear wheel torque threshold. This can prevent the vehicle from becoming dangerous due to excessive torque and ensure that the torque does not exceed the maximum torque that the motor of the wheel can provide.

[0113] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0114] Figure 4 This is a schematic diagram of an embodiment of the three-wheeled vehicle torque determination device provided in this application; the device can be integrated into the controller in the above method embodiment, or it can be implemented through the controller in the above method embodiment. Figure 4 As shown, the tricycle torque determining device 40 includes:

[0115] The acquisition module 41 is used to acquire the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed and road adhesion coefficient during the steering process.

[0116] Processing module 42 is used for:

[0117] The steering torque difference is determined based on the target steering angle, the actual steering angle, and the actual wheel angular velocity.

[0118] Determine the longitudinal drive torque based on the target vehicle speed and the road surface adhesion coefficient;

[0119] The torque determination module 43 is used to determine the left rear wheel torque and the right rear wheel torque based on the target steering angle, steering torque difference and longitudinal drive torque.

[0120] Furthermore, processing module 42 is specifically used for:

[0121] Based on the target steering angle, the actual steering angle, and the actual wheel angular velocity, determine the target angle error and the target wheel angular velocity error;

[0122] The comprehensive error is calculated based on the target angle error, the target wheel rotation angle and angular velocity error, the preset angle weight, and the preset angular velocity weight.

[0123] The steering torque difference is calculated based on the comprehensive error and the PID algorithm.

[0124] Furthermore, processing module 42 is specifically used for:

[0125] The difference between the target steering angle and the actual steering angle is taken as the target angle error;

[0126] Based on the preset correspondence between angle error and wheel rotation angle angular velocity, the target wheel rotation angle angular velocity corresponding to the target angle error is determined. In the correspondence between angle error and wheel rotation angle angular velocity, the angle error is directly proportional to the wheel rotation angle angular velocity.

[0127] The difference between the target wheel's angular velocity and the actual wheel's angular velocity is taken as the target wheel's angular velocity error.

[0128] Furthermore, processing module 42 is specifically used for:

[0129] If the target steering angle sign indicates a left turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque.

[0130] If the target steering angle sign indicates a right turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque.

[0131] Furthermore, module 41 is specifically used for:

[0132] Calculate the current vehicle speed based on the obtained left and right rear wheel speeds;

[0133] Calculate the actual steering angle based on the current vehicle speed, as well as the obtained yaw rate and wheelbase.

[0134] Furthermore, the acquisition module 41 is also used to acquire the left rear wheel speed, the right rear wheel speed, the first left rear wheel torque threshold, and the first right rear wheel torque threshold;

[0135] The processing module 42 is also used to determine, based on the preset correspondence between steering angle, wheel speed and torque threshold, the second left rear wheel torque threshold corresponding to the actual steering angle and the left rear wheel speed, and the second right rear wheel torque threshold corresponding to the actual steering angle and the right rear wheel speed.

[0136] The torque determination module 43 is also used for:

[0137] The minimum value among the left rear wheel torque, the first left rear wheel torque threshold, and the second left rear wheel torque threshold is used as the updated left rear wheel torque;

[0138] The minimum value among the right rear wheel torque, the first right rear wheel torque threshold, and the second right rear wheel torque threshold is used as the updated right rear wheel torque.

[0139] The tricycle torque determination device provided in this embodiment is used to execute the technical solution in any of the aforementioned method embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0140] Figure 5 This is a schematic diagram of the structure of a controller provided in this application. Figure 5 As shown, the controller 50 includes:

[0141] Processor 51, memory 52, and communication interface 53;

[0142] Memory 52 is used to store executable instructions of processor 51;

[0143] The processor 51 is configured to execute the technical solution of the controller in any of the foregoing method embodiments by executing executable instructions.

[0144] Optionally, the memory 52 can be either standalone or integrated with the processor 51.

[0145] Optionally, when the memory 52 is a device independent of the processor 51, the controller 50 may further include:

[0146] Bus 54, memory 52 and communication interface 53 are connected to processor 51 through bus 54 and complete communication with each other. Communication interface 53 is used to communicate with other devices.

[0147] Optionally, the communication interface 53 can be implemented using a transceiver. The communication interface is used to enable communication between the database access device and other devices (e.g., clients, read-write databases, and read-only databases). The memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk drive.

[0148] Bus 54 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, only one thick line is used in the diagram, but this does not indicate that there is only one bus or one type of bus.

[0149] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0150] The controller is used to execute the technical solution of the controller in any of the aforementioned method embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0151] This application also provides a three-wheeled vehicle, which includes a controller, a front wheel, a left rear wheel, and a right rear wheel.

[0152] The front wheel of the tricycle is a driven swivel wheel, while the left and right rear wheels are independently driven drive wheels.

[0153] The controller is used to execute the technical solutions in any of the foregoing method embodiments. Its implementation principle and technical effect are similar, and will not be repeated here.

[0154] This application also provides a readable storage medium storing a computer program thereon, which, when executed by a processor, implements the technical solutions provided in any of the foregoing method embodiments.

[0155] This application also provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the technical solutions provided in any of the foregoing method embodiments.

[0156] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0157] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for determining the torque of a tricycle, characterized in that, The controller applied to a three-wheeled vehicle, the method comprising: During the steering process, the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road adhesion coefficient are obtained. The steering torque difference is determined based on the target steering angle, the actual steering angle, and the actual wheel angular velocity. The longitudinal drive torque is determined based on the target vehicle speed and the road surface adhesion coefficient. Based on the target steering angle, the steering torque difference, and the longitudinal drive torque, the torque of the left rear wheel and the torque of the right rear wheel are determined. The torque of the rear wheel in the same direction as the target steering angle is half of the difference between the longitudinal drive torque and the steering torque difference, and the torque of the other rear wheel in the opposite direction to the target steering angle is half of the sum of the longitudinal drive torque and the steering torque difference. The step of determining the steering torque difference based on the target steering angle, the actual steering angle, and the actual wheel angular velocity includes: Based on the target steering angle, the actual steering angle, and the actual wheel angular velocity, determine the target angle error and the target wheel angular velocity error; The comprehensive error is calculated based on the target angle error, the target wheel rotation angle and angular velocity error, the preset angle weight, and the preset angular velocity weight. The steering torque difference is calculated based on the comprehensive error and the proportional-integral-derivative PID algorithm.

2. The method according to claim 1, characterized in that, The step of determining the target angle error and the target wheel rotation angle error based on the target steering angle, the actual steering angle, and the actual wheel rotation angle angular velocity includes: The difference between the target steering angle and the actual steering angle is taken as the target angle error; Based on the preset correspondence between angle error and wheel rotation angle angular velocity, the target wheel rotation angle angular velocity corresponding to the target angle error is determined, wherein the angle error and wheel rotation angle angular velocity are proportional in the correspondence between angle error and wheel rotation angle angular velocity; The difference between the target wheel's angular velocity and the actual wheel's angular velocity is taken as the target wheel's angular velocity error.

3. The method according to claim 1, characterized in that, The step of determining the left rear wheel torque and right rear wheel torque based on the target steering angle, the steering torque difference, and the longitudinal drive torque includes: If the sign of the target steering angle indicates a left turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the left rear wheel torque, and half of the sum of the differences between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque. If the sign of the target steering angle indicates a right turn, then half of the difference between the longitudinal drive torque and the steering torque is taken as the right rear wheel torque, and half of the sum of the longitudinal drive torque and the steering torque difference is taken as the left rear wheel torque.

4. The method according to claim 1, characterized in that, To obtain the actual steering angle, including: Calculate the current vehicle speed based on the obtained left and right rear wheel speeds; The actual steering angle is calculated based on the current vehicle speed, the obtained yaw rate, and the wheelbase.

5. The method according to any one of claims 1 to 4, characterized in that, The method further includes: Obtain the left rear wheel speed, the right rear wheel speed, the first left rear wheel torque threshold, and the first right rear wheel torque threshold; Based on the preset correspondence between steering angle, wheel speed and torque threshold, a second left rear wheel torque threshold corresponding to the actual steering angle and the left rear wheel speed, and a second right rear wheel torque threshold corresponding to the actual steering angle and the right rear wheel speed are determined. The minimum value among the left rear wheel torque, the first left rear wheel torque threshold, and the second left rear wheel torque threshold is used as the updated left rear wheel torque; The minimum value among the right rear wheel torque, the first right rear wheel torque threshold, and the second right rear wheel torque threshold is used as the updated right rear wheel torque.

6. A device for determining the torque of a tricycle, characterized in that, include: The acquisition module is used to acquire the actual steering angle, target steering angle, actual wheel angular velocity, target vehicle speed, and road adhesion coefficient during the steering process. The processing module is used to determine the steering torque difference based on the target steering angle, the actual steering angle, and the actual wheel rotation angular velocity; The processing module is also used to determine the longitudinal driving torque based on the target vehicle speed and the road surface adhesion coefficient; The torque determination module is used to determine the left rear wheel torque and the right rear wheel torque based on the target steering angle, the steering torque difference, and the longitudinal drive torque. The rear wheel torque in the same direction as the target steering angle is half of the difference between the longitudinal drive torque and the steering torque difference, and the other rear wheel torque in the opposite direction to the target steering angle is half of the sum of the longitudinal drive torque and the steering torque difference. The processing module is specifically used for: Based on the target steering angle, the actual steering angle, and the actual wheel angular velocity, determine the target angle error and the target wheel angular velocity error; The comprehensive error is calculated based on the target angle error, the target wheel rotation angle and angular velocity error, the preset angle weight, and the preset angular velocity weight. The steering torque difference is calculated based on the comprehensive error and the proportional-integral-derivative PID algorithm.

7. A controller, characterized in that, include: Processor, memory, communication interface; The memory is used to store the executable instructions of the processor; The processor is configured to execute the tricycle torque determination method according to any one of claims 1 to 5 by executing the executable instructions.

8. A three-wheeled vehicle, characterized in that, Including the controller; The controller is used to execute the tricycle torque determination method according to any one of claims 1 to 5.

9. A readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for determining the torque of a three-wheeled vehicle as described in any one of claims 1 to 5.

10. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, is used to implement the method for determining the torque of a three-wheeled vehicle as described in any one of claims 1 to 5.

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