Control method and device of moving tool, electronic equipment, moving tool and medium

Abstract

The invention relates to a mobile tool control method and device, electronic equipment, a mobile tool and a medium, and the method comprises the steps: calculating a radius difference value between a minimum theoretical turning radius and a target turning radius when the minimum theoretical turning radius corresponding to a walking wheel of the mobile tool is greater than the target turning radius corresponding to a target path point; calculating the rotating speed of a walking wheel of the moving tool based on the radius difference value; wherein the rotating speeds of the walking wheels on the two sides of the moving tool are different; and controlling the moving tool to run based on the rotating speed of the walking wheel of the moving tool. According to the scheme, the wheel speed, obtained through calculation of the radius difference value, of the walking wheel can compensate the angle which cannot be rotated due to the limitation of the geometric structure of the moving tool, and therefore the driving accuracy and safety of the moving tool in the turning process are improved.

Description

Technical Field

[0001] The present application relates to the field of autonomous driving technology, and in particular to a control method, device, electronic device, mobile tool and medium for a mobile tool. Background Art

[0002] In the field of autonomous driving, accurate and reliable control strategies will directly affect the driving stability of mobile vehicles, especially during the turning process of mobile vehicles. If the control strategy is not accurate enough, the mobile vehicle may be at risk of rollover during the turning process.

[0003] In the related technology, traditional control strategies usually control mobile tools based on Ackerman steering chassis. However, if the mobile tool is traveling on a road with a small turning radius, due to the geometric structure limitations of the Ackerman steering chassis, the running wheels of the mobile tool have a corresponding minimum theoretical turning radius. If the minimum theoretical turning radius corresponding to the running wheels of the mobile tool is greater than the target turning radius of the road at the current trajectory point, the mobile tool cannot pass through this section of road normally. Controlling the driving of the mobile tool according to the traditional control algorithm is likely to cause safety accidents. Summary of the invention

[0004] In order to solve or partially solve the problems existing in the related art, the present application provides a control method, device, electronic device, mobile tool and medium for a mobile tool, which can control the mobile tool to travel safely and accurately during a turn.

[0005] A first aspect of the present application provides a control method for a mobile tool, the method comprising:

[0006] When the minimum theoretical turning radius corresponding to the traveling wheels of the mobile tool is greater than the target turning radius corresponding to the target path point, calculating the radius difference between the minimum theoretical turning radius and the target turning radius;

[0007] Based on the radius difference, the rotation speed of the running wheels of the mobile tool is calculated; wherein the rotation speeds of the running wheels on both sides of the mobile tool are different;

[0008] The movement of the mobile tool is controlled based on the rotation speed of the running wheels of the mobile tool.

[0009] According to the control method of the mobile tool provided in the present application, the mobile tool is controlled to travel based on the rotation speed of the running wheels of the mobile tool, including:

[0010] Determining the steering angle of the wheel axle of the mobile tool at the target path point;

[0011] Determining a steering control amount of the mobile tool based on the steering angle of the wheel axle and the rotation speed of the travel wheel;

[0012] Based on the steering control amount, the moving tool is controlled to travel.

[0013] According to the control method of the mobile tool provided in the present application, determining the steering angle of the wheel axle of the mobile tool at the target path point includes:

[0014] Acquire geometric parameters of the mobile tool and motion parameters of the mobile tool at the target path point;

[0015] Establishing a motion state model corresponding to the mobile tool; wherein the motion state model is used to characterize the corresponding relationship between the steering angle of the wheel axle of the mobile tool and the geometric parameters and motion parameters of the mobile tool;

[0016] Based on the motion state model, the geometric parameters of the mobile tool and the motion parameters of the mobile tool at the target path point, the steering angle of the wheel axle of the mobile tool at the target path point is obtained.

[0017] According to the control method of the mobile tool provided in the present application, the mobile tool includes a first axle, a second axle, a third axle and a fourth axle;

[0018] Establishing a motion state model corresponding to the mobile tool includes:

[0019] Merging the first wheel axle with the second wheel axle to obtain a first axle model;

[0020] Merging the third wheel axle with the fourth wheel axle to obtain a second axle model;

[0021] A motion state model corresponding to the moving tool is established based on the first axis model and the second axis model.

[0022] According to the control method of the mobile tool provided in the present application, the process of determining the target turning radius corresponding to the target path point includes:

[0023] Obtaining the angle between the preview line and the X-axis of the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle; wherein the preview line is formed by connecting the center point of the wheel axle of the mobile tool and the preview point in the driving trajectory;

[0024] Based on the angle between the preview straight line and the X-axis in the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle, the target turning radius corresponding to the target path point is determined.

[0025] According to the control method of the mobile tool provided in the present application, the rotation speed of the travel wheel of the mobile tool is calculated based on the radius difference, including:

[0026] Based on the radius difference, calculating the turning radius of the traveling wheels of the mobile tool;

[0027] The rotation speed of the traveling wheel is calculated based on the turning radius of the traveling wheel.

[0028] A second aspect of the present application provides a control device for a mobile tool, the device comprising:

[0029] A processing module, configured to calculate a radius difference between the minimum theoretical turning radius and the target turning radius when the minimum theoretical turning radius corresponding to the traveling wheels of the mobile tool is greater than the target turning radius corresponding to the target path point;

[0030] A calculation module, used for calculating the rotation speed of the running wheels of the mobile tool based on the radius difference; wherein the rotation speeds of the running wheels on both sides of the mobile tool are different;

[0031] The control module is used to control the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool.

[0032] A third aspect of the present application provides an electronic device, including:

[0033] Processor; and

[0034] The memory stores executable codes thereon, and when the executable codes are executed by the processor, the processor is caused to execute the method as described above.

[0035] A fourth aspect of the present application provides a mobile tool, comprising: a plurality of data sources and the electronic device as described above, wherein the data source is communicatively connected with the electronic device.

[0036] A fifth aspect of the present application provides a computer-readable storage medium having executable code stored thereon. When the executable code is executed by a processor of an electronic device, the processor is caused to execute the method as described above.

[0037] The technical solution provided by this application may have the following beneficial effects:

[0038] When the minimum theoretical turning radius corresponding to the traveling wheels of the mobile tool is greater than the target turning radius corresponding to the target path point, the radius difference between the minimum theoretical turning radius and the target turning radius is calculated, and based on the radius difference, the rotational speed of the traveling wheels of the mobile tool is further calculated. Finally, the driving of the mobile tool is controlled based on the rotational speed of the traveling wheels of the mobile tool. Since the wheel speed of the traveling wheels calculated by the radius difference can compensate for the angle that cannot be turned due to the geometric structure of the mobile tool, the driving accuracy and safety of the mobile tool during the turning process are improved.

[0039] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and other objects, features and advantages of the present application will become more apparent by describing in more detail exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0041] Figure 1 is a flow chart of a control method of a mobile tool shown in an embodiment of the present application;

[0042] Figure 2 It is a structural schematic diagram of the Ackerman steering geometry model corresponding to the mobile tool using a four-axis drive chassis in the embodiment of the present application;

[0043] Figure 3 This is a schematic diagram of the control principle of the mobile tool during the turning process in the embodiment of the present application;

[0044] Figure 4 is a schematic structural diagram of a control device for a mobile tool shown in an embodiment of the present application;

[0045] Figure 5 is a schematic diagram of the structure of an electronic device shown in an embodiment of the present application;

[0046] Figure 6 It is a schematic diagram of the structure of the mobile tool shown in the embodiment of the present application. DETAILED DESCRIPTION

[0047] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0048] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0049] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0050] In the field of intelligent driving, the autonomous tracking function of mobile tools is mainly implemented based on mature control algorithms, such as pure tracking algorithms, Stanley (also known as front wheel feedback control method) and other geometric control tracking algorithms, or LQR (Linear Quadratic Regulator), MPC (Model Predictive Control) and other numerical optimization tracking algorithms. The above control algorithms are mainly based on the Ackerman steering chassis on structured roads. Limited by the geometric structure of the Ackerman steering chassis, the mobile tool has a corresponding minimum theoretical turning radius. If the target turning radius corresponding to the target path point is smaller than the minimum theoretical turning radius during driving on the road, in this case, the control algorithm implemented based on the Ackerman steering chassis is difficult to control the mobile tool to accurately pass through this section of road, resulting in certain safety hazards in the driving process of the mobile tool.

[0051] In response to the above problems, an embodiment of the present application provides a control method for a mobile tool. The method can be applied to an autonomous tracking scenario of a mobile tool with an intelligent driving function, and can improve the driving reliability and safety of the mobile tool.

[0052] Figure 1 It is a flow chart of a control method of a mobile tool shown in an embodiment of the present application.

[0053] See also Figure 1 An embodiment of the present application provides a method for controlling a mobile tool, the method comprising:

[0054] Step 101: when the minimum theoretical turning radius corresponding to the travel wheel of the mobile tool is greater than the target turning radius corresponding to the target path point, calculating the radius difference between the minimum theoretical turning radius and the target turning radius;

[0055] Step 102: Calculate the rotation speed of the running wheels of the mobile tool based on the radius difference; wherein the rotation speeds of the running wheels on both sides of the mobile tool are different;

[0056] Step 103: Controlling the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool.

[0057] In practical applications, the control method of the mobile tool provided in the present application can be applied to a management device, and the management device may include one or more management terminals and / or one or more management servers.

[0058] It can be understood that this embodiment is aimed at the situation where the minimum theoretical turning radius corresponding to the walking wheel of the mobile tool is larger than the target turning radius corresponding to the target path point. In this case, if only based on the traditional Ackerman steering control algorithm, it is difficult to accurately drive at the current target path point. In this case, this embodiment will calculate the radius difference between the minimum theoretical turning radius and the target turning radius. The radius difference is a positive number. For example, the minimum theoretical turning radius can be subtracted from the target turning radius, and the absolute value of the difference between the two can be taken as the radius difference.

[0059] In a specific implementation, the traveling wheels of the mobile tool can be grouped according to their distribution. For example, two traveling wheels located on the left and right sides of the mobile tool on the same axle are grouped as one traveling wheel, and the rotation speed of each traveling wheel is determined separately. In order to realize differential steering, the wheel speeds of the traveling wheels on both sides of the mobile tool need to be different.

[0060] Through the different rotation speeds of the traveling wheels on both sides of the mobile tool, the wheel axle of the mobile tool can produce a corresponding steering angle, thereby compensating for the angle that the mobile tool cannot turn corresponding to the radius difference, so that the mobile tool can pass the target path point accurately and safely.

[0061] In one embodiment, controlling the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool specifically includes:

[0062] determining a steering angle of a wheel axle of a mobile tool at a target waypoint;

[0063] Determine the steering control amount of the mobile tool based on the steering angle of the wheel axle and the rotation speed of the travel wheel;

[0064] Based on the steering control amount, the movement of the mobile tool is controlled.

[0065] It can be understood that the steering angle of the wheel axle of the mobile tool at the target path point can be the steering control amount for the mobile tool preliminarily determined by the Ackerman steering scheme, but when the minimum theoretical turning radius corresponding to the running wheels of the mobile tool is greater than the target turning radius corresponding to the target path point, the steering control amount preliminarily determined based on the Ackerman steering scheme cannot accurately control the mobile tool to turn safely.

[0066] To this end, the present embodiment introduces the rotational speed of the traveling wheels. Through the rotational speed difference of the traveling wheels on both sides of the mobile tool, the wheel axle can further generate a corresponding steering angle, thereby compensating for the steering angle of the wheel axle that is initially determined. Specifically, the steering control amount of the mobile tool can be comprehensively determined based on the steering angle of the wheel axle and the rotational speed of the traveling wheels, thereby achieving the purpose of accurately controlling the driving of the mobile tool.

[0067] In one embodiment, determining the steering angle of the wheel axle of the mobile tool at the target path point specifically includes:

[0068] Obtaining geometric parameters of the moving tool and motion parameters of the moving tool at the target path point;

[0069] Establishing a motion state model corresponding to the mobile tool; wherein the motion state model is used to characterize the corresponding relationship between the steering angle of the wheel axle of the mobile tool and the geometric parameters and motion parameters of the mobile tool;

[0070] Based on the motion state model, the geometric parameters of the mobile tool and the motion parameters of the mobile tool at the target path point, the steering angle of the wheel axle of the mobile tool at the target path point is obtained.

[0071] It can be understood that the geometric parameters of the mobile tool can be the theoretical parameters corresponding to the mobile tool under the current structure. For example, the geometric parameters can include the vertical distance from the geometric center of the mobile tool to each axle, the vertical distance from the center of two axles to other axles, the mass of the mobile tool, the tire lateral stiffness corresponding to each axle, and other static parameters.

[0072] The motion parameters of the mobile tool at the target path point may be dynamic parameters such as the driving speed of the mobile tool at the target path point, the rotation speed of each walking wheel, the steering angle of each wheel axle, the yaw angle of the mobile tool, the lateral deviation of the mobile tool, and the heading deviation.

[0073] The motion state model corresponding to the mobile tool can be established based on the Ackermann steering geometry model corresponding to the mobile tool. Specifically, the kinematic model of the mobile tool can be established based on the Ackermann steering geometry model, and then the kinematic model can be converted into the state space to obtain the motion state model of the mobile tool.

[0074] By building a good motion state model, the steering angle of the wheel axle of the mobile tool at the target path point can be obtained through optimization solution. In practical applications, the optimization solution can be achieved by constructing an LQR objective function.

[0075] In one embodiment, the mobile tool may specifically include a first axle, a second axle, a third axle, and a fourth axle;

[0076] Establish the motion state model corresponding to the mobile tool, including:

[0077] The first axle is combined with the second axle to obtain a first axle model;

[0078] The third axle is combined with the fourth axle to obtain the second axle model;

[0079] A motion state model corresponding to the moving tool is established based on the first axis model and the second axis model.

[0080] It can be understood that in this embodiment, the mobile tool adopts a four-axle drive chassis, and the four axles are specifically the first axle, the second axle, the third axle and the fourth axle in the arrangement direction from the front end to the rear end of the mobile tool, among which the first axle and the second axle satisfy the Ackerman steering geometry constraint, and the four axles all satisfy the differential steering geometry constraint.

[0081] Figure 2 The Ackerman steering geometry model corresponding to a mobile tool with a four-axis drive chassis is shown as an example, see Figure 2 After the four-axis drive chassis structure is simplified, there are four axles and four sets of running wheels. The entire structure is established in the UTM (Universal Transverse Mercator Grid System) coordinate system, with the origin of the coordinate being O, and the two coordinate axes being the X-axis and the Y-axis.

[0082] Among them, O1 is the geometric center of the mobile tool, v x is the longitudinal speed of the mobile tool, v li 、v ri is the wheel speed of the left and right wheels (in m / s), δ1 is the steering angle of the first axle, δ2 is the steering angle of the second axle, l f is the vertical distance from the geometric center to the first wheel axis, l r is the vertical distance from the geometric center to the fourth wheel axle, L is the vertical distance from the center point of the third wheel axle and the fourth wheel axle to the first wheel axle, Φ is the yaw angle of the mobile tool in the UTM coordinate system, I z is the moment of inertia of the geometric center, θ is the orientation of the trajectory point (x1, y1) in the UTM coordinate system, d is the lateral deviation between the geometric center and the nearest trajectory point (x1, y1) on the reference trajectory, x1 is the x-coordinate of the trajectory point closest to the geometric center of the mobile tool in the UTM coordinate system, and y1 is the y-coordinate of the trajectory point closest to the geometric center of the mobile tool in the UTM coordinate system.

[0083] Based on the Ackerman steering geometry model, Figure 2The first axle and the second axle are combined to obtain the first axle model, which is the first axle. The third axle and the fourth axle are combined to obtain the second axle model, which is the fourth axle. That is to say, the first axle and the fourth axle are retained, and the kinematic model corresponding to the mobile tool is established based on the first axle and the fourth axle. In practical applications, the kinematic model of the mobile tool is as follows:

[0084]

[0085] In the formula, e1, are the lateral deviation of the moving tool and the rate of change of the lateral deviation, e2, are the heading deviation and the rate of change of heading deviation, C af is the tire cornering stiffness of the first and second axles, C ar is the tire cornering stiffness of the third and fourth axles, m is the mass of the mobile tool, i.e. the mass of the vehicle, v x is the longitudinal speed of the mobile tool, l f is the vertical distance from the geometric center to the first wheel axis, l r is the vertical distance from the geometric center to the fourth wheel axis, I z is the moment of inertia of the geometric center, u * is the expected control quantity.

[0086] Converting the above kinematic model to the state space, the obtained motion state model is as follows:

[0087]

[0088] e1=cos(θ)*(x-x1)-sin(θ)*(y-y1) (3)

[0089] e2=θ-Φ (4)

[0090] In the formula, the state variable x is the motion state matrix of the mobile tool, A is the coefficient matrix of the motion state matrix, and u * is the desired control amount, B is the coefficient matrix of the desired control amount, e1 is the lateral deviation of the mobile tool, θ is the orientation of the trajectory point (x1, y1) in the UTM coordinate system, Φ is the yaw angle of the mobile tool in the UTM coordinate system, and e2 is the heading deviation.

[0091] Based on the kinematic model and motion state model of the mobile tool, if the motion state matrix x (i.e., the lateral deviation and its rate of change, and the heading deviation and its rate of change of the mobile tool) is made stable, and the desired control amount u * The cost is relatively small, and can be solved by constructing an LQR objective function for optimization. For example, the objective function can be as follows:

[0092]

[0093] In the formula, J is the cost, the smaller the value of J, the better. min That is the minimum cost, Q is the weight coefficient matrix of the state variable x, and M is the weight coefficient matrix of the control variable u.

[0094] On this basis, the algebraic Riccati matrix can be established for iterative optimization, and finally the current optimal expected control quantity u can be obtained. * .

[0095] It can be understood that according to the desired control amount u * , the steering angle δ1 of the first wheel axle and the steering angle δ2 of the second wheel axle can be determined. The specific corresponding relationship is as follows:

[0096] δ1=u * ,δ1=k*δ2(0 <k<1) (6)

[0097] From the above formula (6), we can know that according to the desired control quantity u * The steering angle δ1 of the first axle can be directly determined, and then the steering angle δ2 of the second axle can be determined based on the fixed proportional relationship k between the steering angle δ1 of the first axle and the steering angle δ2 of the second axle to obtain the steering angle of the axle of the mobile tool at the target path point.

[0098] In one embodiment, the process of determining the target turning radius corresponding to the target path point specifically includes:

[0099] Obtain the angle between the preview line and the X-axis of the coordinate system where the mobile tool is located, and the distance between the geometric center of the mobile tool and the wheel axle; wherein the preview line is formed by connecting the center point of the wheel axle of the mobile tool and the preview point in the driving trajectory;

[0100] The target turning radius corresponding to the target path point is determined based on the angle between the preview line and the X-axis of the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle.

[0101] It can be understood that the coordinate system where the mobile tool is located can be the above-mentioned UTM coordinate system, and the preview point in the driving trajectory of the mobile tool can be determined according to the preset preview distance d1.

[0102] by Figure 2 Taking the Ackerman steering geometry model corresponding to the four-axle drive chassis shown in the figure as an example, the target turning radius corresponding to the target path point can be calculated as follows:

[0103]

[0104] Where R1 is the target turning radius, l fis the vertical distance from the geometric center of the mobile tool to the first wheel axle, and α is the angle between the preview straight line formed by connecting the center point of the wheel axle of the mobile tool and the preview point in the driving trajectory, and the X-axis in the coordinate system where the mobile tool is located.

[0105] In one embodiment, the rotation speed of the travel wheel of the mobile tool is calculated based on the radius difference, specifically including:

[0106] Based on the radius difference, the turning radius of the travel wheel of the mobile tool is calculated;

[0107] Based on the turning radius of the travel wheel, the rotational speed of the travel wheel is calculated.

[0108] In this embodiment, the radius difference ΔR between the minimum theoretical turning radius R and the target turning radius R1 can be expressed as follows:

[0109] ΔR=R-R1 (8)

[0110] It can be understood that the radius difference ΔR is a positive number greater than 0. After the radius difference ΔR is determined, the steering radius of the running wheels on both sides of the mobile tool can be determined according to the proportional relationship between the radius difference ΔR and the steering radius corresponding to the running wheels on both sides of the mobile tool during differential steering. Then, the rotation speed of the running wheels on both sides of the mobile tool can be calculated based on the steering radius of the running wheels on both sides of the mobile tool. The specific calculation formula is as follows:

[0111]

[0112] In the formula, R l and R r They are the steering radius of the left and right wheels of the mobile tool during differential steering, respectively. They are proportional to the radius difference ΔR. The proportional coefficients are k1 and k2, respectively. k1 and k2 can be determined according to the chassis width of the mobile tool. v x is the longitudinal speed of the mobile tool, v li and v ri are the rotation speeds of the left and right wheels of the mobile tool, respectively. f It is the vertical distance from the geometric center of the moving tool to the first wheel axis.

[0113] The radius difference ΔR can be used to set the rotation speed of the left and right wheels of the mobile tool to be inconsistent, so as to achieve the purpose of slip, so that the mobile tool turns the wheel axle steering angle δ corresponding to the radius difference ΔR s .

[0114] After obtaining the rotation speed of the traveling wheel, the steering control amount of the mobile tool can be determined based on the predetermined steering angle of the wheel axle and the rotation speed of the traveling wheel. In this embodiment, the steering control amount of the mobile tool can be the steering angle δ1 of the first wheel axle, the steering angle δ2 of the second wheel axle, the rotation speed v of each traveling wheel on the left side of the mobile tool, and the steering angle δ1 of the first wheel axle, the steering angle δ2 of the second wheel axle, and the rotation speed v of each traveling wheel on the left side of the mobile tool. li And the speed v of each right wheel ri .

[0115] According to the above steering control amount, the target steering angle of the moving tool at the target path point is:

[0116] δ=δ s +u * (10)

[0117] Where δ is the target steering angle, and the radius difference ΔR corresponds to the axle steering angle δ s ,u * is the desired control variable, namely the steering angle δ1 of the first axle and the steering angle δ2 of the second axle.

[0118] The target steering angle obtained after compensation can enable the mobile tool to pass the target path point safely and accurately.

[0119] Figure 3 The control principle of the mobile tool during the turning process is exemplarily shown. The control process is implemented by the positioning unit 301, the decision unit 302, the processing unit 303 and the mobile tool 300. The positioning unit 301 can output the yaw angle Φ of the mobile tool and the coordinate values ​​x, y of the real-time position point of the mobile tool in the UTM coordinate system. The decision unit 302 can output the reference trajectory, the coordinate values ​​x1, y1 of the trajectory point closest to the mobile tool on the reference trajectory, and the orientation θ of the trajectory point (x1, y1) in the UTM coordinate system.

[0120] The data output by the positioning unit 301 and the decision unit 302 can be input into the LQR objective function for solution, and the desired control amount u is output after the solution. * ;

[0121] At the same time, the minimum theoretical turning radius R of the mobile tool is compared with the target turning radius R1 determined by the pure tracking algorithm. If the target turning radius R1 is smaller than the minimum theoretical turning radius R, the radius difference ΔR is further determined, and the speed v of each walking wheel on the left side of the mobile tool is further determined by the differential steering algorithm. li And the speed v of each right wheel ri ;

[0122] After that, the desired control quantity u * , the speed v of each wheel on the left side of the mobile tool li And the speed v of each right wheelri are input into the processing unit 303, and after being processed by the processing unit 303, the desired control amount u is output. * The corresponding steering angle δ1 of the first wheel axle, the steering angle δ2 of the second wheel axle, and the speed v of each walking wheel on the left side of the mobile tool li And the speed v of each right wheel ri ;

[0123] Finally, the steering angle δ1 of the first wheel axle, the steering angle δ2 of the second wheel axle, and the rotation speed v of each walking wheel on the left side of the mobile tool are calculated. li And the speed v of each right wheel ri Sent to the mobile tool 300, for example, can be sent to the controller of the mobile tool 300, so as to control the mobile tool 300 to accurately drive through the target path point.

[0124] In actual applications, the processing unit 303 can be a processor or server with data processing capabilities. The processing unit 303 can be deployed on the mobile tool 300, or it can be deployed outside the mobile tool 300 and connected to the mobile tool 300 through a network. The network can be a wired network or a wireless network.

[0125] Corresponding to the aforementioned application function implementation method embodiment, the present application also provides a mobile tool control device, an electronic device, a mobile tool and corresponding embodiments.

[0126] Figure 4 It is a schematic diagram of the structure of a control device for a mobile tool shown in an embodiment of the present application.

[0127] See also Figure 4 , a control device for a mobile tool provided in an embodiment of the present application specifically includes:

[0128] The processing module 401 is used to calculate the radius difference between the minimum theoretical turning radius and the target turning radius when the minimum theoretical turning radius corresponding to the running wheel of the mobile tool is greater than the target turning radius corresponding to the target path point;

[0129] A calculation module 402 is used to calculate the rotation speed of the travel wheel of the mobile tool based on the radius difference;

[0130] The control module 403 is used to control the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool.

[0131] In one embodiment, the control module 403 may be specifically used for:

[0132] determining a steering angle of a wheel axle of a mobile tool at a target waypoint;

[0133] Determine the steering control amount of the mobile tool based on the steering angle of the wheel axle and the rotation speed of the travel wheel;

[0134] Based on the steering control amount, the movement of the mobile tool is controlled.

[0135] In one embodiment, in the control module 403, determining the steering angle of the wheel axle of the mobile tool at the target path point specifically includes:

[0136] Obtaining geometric parameters of the moving tool and motion parameters of the moving tool at the target path point;

[0137] Establishing a motion state model corresponding to the mobile tool; wherein the motion state model is used to characterize the corresponding relationship between the steering angle of the wheel axle of the mobile tool and the geometric parameters and motion parameters of the mobile tool;

[0138] Based on the motion state model, the geometric parameters of the mobile tool and the motion parameters of the mobile tool at the target path point, the steering angle of the wheel axle of the mobile tool at the target path point is obtained.

[0139] In one embodiment, the mobile tool includes a first axle, a second axle, a third axle, and a fourth axle;

[0140] In the control module 403, a motion state model corresponding to the mobile tool is established, which specifically includes:

[0141] The first axle is combined with the second axle to obtain a first axle model;

[0142] The third axle is combined with the fourth axle to obtain the second axle model;

[0143] A motion state model corresponding to the moving tool is established based on the first axis model and the second axis model.

[0144] In one embodiment, the control device of the mobile tool may further include:

[0145] The determination module is used to determine the target turning radius corresponding to the target path point, specifically for:

[0146] Obtain the angle between the preview line and the X-axis of the coordinate system where the mobile tool is located, and the distance between the geometric center of the mobile tool and the wheel axle; wherein the preview line is formed by connecting the center point of the wheel axle of the mobile tool and the preview point in the driving trajectory;

[0147] The target turning radius corresponding to the target path point is determined based on the angle between the preview line and the X-axis of the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle.

[0148] In one embodiment, the calculation module 402 may be specifically used for:

[0149] Based on the radius difference, the turning radius of the travel wheel of the mobile tool is calculated;

[0150] Based on the turning radius of the travel wheel, the rotational speed of the travel wheel is calculated.

[0151] To sum up, the control device of the mobile tool provided in the embodiment of the present application can compensate for the angle that cannot be turned due to the geometric structure limitations of the mobile tool, because the wheel speed of the walking wheel is calculated by the radius difference, thereby improving the driving accuracy and safety of the mobile tool during turning.

[0152] Figure 5 It is a schematic diagram of the structure of an electronic device shown in an embodiment of the present application.

[0153] See also Figure 5 The electronic device 500 includes a memory 510 and a processor 520. It can be understood that the electronic device may include one or more data processing terminals and / or one or more servers with data processing functions.

[0154] The processor 520 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0155] The memory 510 may include various types of storage units, such as system memory, read-only memory (ROM), and permanent storage. Among them, ROM can store static data or instructions required by the processor 520 or other modules of the computer. The permanent storage device may be a readable and writable storage device. The permanent storage device may be a non-volatile storage device that does not lose the stored instructions and data even after the computer is powered off. In some embodiments, the permanent storage device uses a large-capacity storage device (such as a magnetic or optical disk, flash memory) as a permanent storage device. In other embodiments, the permanent storage device may be a removable storage device (such as a floppy disk, optical drive). The system memory may be a readable and writable storage device or a volatile readable and writable storage device, such as a dynamic random access memory. The system memory may store some or all instructions and data required by the processor at run time.

[0156] In addition, the memory 510 may include any combination of computer-readable storage media, including various types of semiconductor memory chips (e.g., DRAM, SRAM, SDRAM, flash memory, programmable read-only memory), and magnetic disks and / or optical disks may also be used. In some embodiments, the memory 510 may include a removable storage device that can be read and / or written, such as a laser disc (CD), a read-only digital versatile disk (e.g., DVD-ROM, double-layer DVD-ROM), a read-only Blu-ray disk, an ultra-density optical disk, a flash memory card (e.g., SD card, min SD card, Micro-SD card, etc.), a magnetic floppy disk, etc. Computer-readable storage media do not include carrier waves and transient electronic signals transmitted wirelessly or wired.

[0157] The memory 510 stores executable codes, and when the executable codes are processed by the processor 520 , the processor 520 can execute part or all of the methods described above.

[0158] See also Figure 6 An embodiment of the present application further provides a mobile tool 300, which includes: multiple data sources 600 and the above-mentioned electronic device 500, and the data source 600 is communicatively connected with the electronic device 500.

[0159] In some embodiments, the data source 600 may be a device such as a positioning unit, a decision unit, or may be a data acquisition device such as a sensor or a camera on a mobile tool.

[0160] It is understood that the mobile tool 300 in this embodiment includes but is not limited to a vehicle with six autonomous driving technology levels of L0-L5 as specified by the Society of Automotive Engineers International (SAE International) or the Chinese national standard "Automotive Driving Automation Classification", for example, a vehicle device or a robot device having the following functions:

[0161] (1) Passenger-carrying function, such as family cars and buses;

[0162] (2) Cargo-carrying functions, such as ordinary trucks, van trucks, trailer trucks, closed trucks, tank trucks, flatbed trucks, container trucks, dump trucks, trucks with special structures, etc.;

[0163] (3) Tool functions, such as logistics delivery vehicles, automated guided vehicles (AGVs), patrol cars, cranes, hoists, excavators, bulldozers, forklifts, road rollers, loaders, off-road engineering vehicles, armored engineering vehicles, sewage treatment vehicles, sanitation vehicles, vacuum trucks, floor scrubbers, water sprinklers, sweeping robots, food delivery robots, shopping guide robots, lawn mowers, golf carts, etc.;

[0164] (4) Entertainment functions, such as entertainment vehicles, amusement park self-driving devices, balance vehicles, etc.;

[0165] (5) Special rescue functions, such as fire trucks, ambulances, power repair vehicles, engineering rescue vehicles, etc.

[0166] This application does not strictly limit the types of mobile tools, and no exhaustive list is given here.

[0167] By configuring the above electronic equipment, the mobile tool in this embodiment can travel accurately and safely on a road with a small turning radius, thereby improving the driving stability of the mobile tool.

[0168] In addition, the method according to the present application may also be implemented as a computer program or a computer program product, which includes computer program code instructions for executing some or all of the steps in the above method of the present application.

[0169] Alternatively, the present application can also be implemented as a computer-readable storage medium (or non-transitory machine-readable storage medium or machine-readable storage medium) on which executable code (or computer program or computer instruction code) is stored. When the executable code (or computer program or computer instruction code) is executed by a processor of an electronic device (or server, etc.), the processor executes part or all of the steps of the above-mentioned method according to the present application.

[0170] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for controlling a mobile tool, characterized in that: include: When the minimum theoretical turning radius corresponding to the traveling wheels of the mobile tool is greater than the target turning radius corresponding to the target path point, calculating the radius difference between the minimum theoretical turning radius and the target turning radius; Based on the radius difference, the rotation speed of the running wheels of the mobile tool is calculated; wherein the rotation speeds of the running wheels on both sides of the mobile tool are different; The movement of the mobile tool is controlled based on the rotation speed of the running wheels of the mobile tool.

2. The control method of a mobile tool according to claim 1, characterized in that: Controlling the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool comprises: Determining the steering angle of the wheel axle of the mobile tool at the target path point; Determining a steering control amount of the mobile tool based on the steering angle of the wheel axle and the rotation speed of the travel wheel; Based on the steering control amount, the moving tool is controlled to travel.

3. The control method of a mobile tool according to claim 2, characterized in that: Determining the steering angle of the wheel axle of the mobile tool at the target path point includes: Acquire geometric parameters of the mobile tool and motion parameters of the mobile tool at the target path point; Establishing a motion state model corresponding to the mobile tool; wherein the motion state model is used to characterize the corresponding relationship between the steering angle of the wheel axle of the mobile tool and the geometric parameters and motion parameters of the mobile tool; Based on the motion state model, the geometric parameters of the mobile tool and the motion parameters of the mobile tool at the target path point, the steering angle of the wheel axle of the mobile tool at the target path point is obtained.

4. The control method of a mobile tool according to claim 3, characterized in that: The mobile tool includes a first axle, a second axle, a third axle and a fourth axle; Establishing a motion state model corresponding to the mobile tool includes: Merging the first wheel axle with the second wheel axle to obtain a first axle model; Merging the third wheel axle with the fourth wheel axle to obtain a second axle model; A motion state model corresponding to the moving tool is established based on the first axis model and the second axis model.

5. The control method of a mobile tool according to claim 1, characterized in that: The process of determining the target turning radius corresponding to the target path point includes: Obtaining the angle between the preview line and the X-axis of the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle; wherein the preview line is formed by connecting the center point of the wheel axle of the mobile tool and the preview point in the driving trajectory; Based on the angle between the preview straight line and the X-axis in the coordinate system of the mobile tool, and the distance between the geometric center of the mobile tool and the wheel axle, the target turning radius corresponding to the target path point is determined.

6. The control method of a mobile tool according to claim 1, characterized in that: Calculating the rotation speed of the travel wheel of the mobile tool based on the radius difference includes: Based on the radius difference, calculating the turning radius of the traveling wheels of the mobile tool; The rotation speed of the traveling wheel is calculated based on the turning radius of the traveling wheel.

7. A control device for a mobile tool, characterized in that: include: A processing module, configured to calculate a radius difference between the minimum theoretical turning radius and the target turning radius when the minimum theoretical turning radius corresponding to the traveling wheels of the mobile tool is greater than the target turning radius corresponding to the target path point; A calculation module, used for calculating the rotation speed of the running wheels of the mobile tool based on the radius difference; wherein the rotation speeds of the running wheels on both sides of the mobile tool are different; The control module is used to control the movement of the mobile tool based on the rotation speed of the running wheels of the mobile tool.

8. An electronic device, characterized in that: include: processor; as well as A memory having executable codes stored thereon, which, when executed by the processor, causes the processor to execute the method according to any one of claims 1 to 6.

9. A mobile tool, characterized in that: include: A plurality of data sources and the electronic device as claimed in claim 8, wherein the data sources are communicatively connected with the electronic device.

10. A computer-readable storage medium, characterized in that: An executable code is stored thereon, and when the executable code is executed by a processor of an electronic device, the processor is caused to execute the method as claimed in any one of claims 1 to 6.

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