Speed planning method and device for enhancing turning capability of wheeled robot and robot

Abstract

The invention discloses a speed planning method and device for enhancing the turning capacity of a wheeled robot and the robot. The speed planning method for enhancing the turning capability of the wheeled robot comprises the following steps: determining a kinematics relation of the wheeled robot during turning according to a chassis inverse kinematics model of a differential motion robot; calculating according to the kinematics relation and the physical characteristics of the outer side wheel to obtain the speed of the motion center; and calculating according to the preset curvature, the physical characteristics of the outer side wheel and the speed of the motion center to obtain the speed of the inner side wheel. The technical effects that the control performance and adaptability of the wheeled robot can be improved, and speed planning of the wheeled robot in the advancing process is achieved can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of computer technology applications, and in particular to a speed planning method, a device and a robot for enhancing the cornering ability of a wheeled robot. Background Art

[0002] In the prior art, when a wheeled robot passes a curve, the center of motion generally maintains a constant cornering speed, or relies on combined acceleration limitation and actual curvature distribution to limit the change of the cornering speed.

[0003] However, the existing technology still cannot solve the problem that when the peak curvature is large or the curvature change rate is large, the robot is prone to overshoot, or the required speed on the wheel exceeds the upper limit of the actuator and cannot be executed. The state of the lateral acceleration is not a directly corresponding state, but a state after comprehensive conversion and mapping, which makes it inconvenient to control the state on the actuator according to the lateral acceleration.

[0004] Currently, no effective solution has been proposed to address the problem that in related technologies, speed planning does not take the actuator capability into consideration but only focuses on the speed planning of the motion center, resulting in unreasonable speed instructions that make the end effector unable to be implemented. Summary of the invention

[0005] In order to solve the above technical problems, the embodiments of the present invention hope to provide a speed planning method, device and wheeled robot with enhanced cornering ability of a wheeled robot, so as to at least solve the problem that in the related technology, the speed planning does not take the actuator capability into consideration but only focuses on the speed planning of the motion center, resulting in unreasonable speed instructions that make it impossible for the end effector to be implemented.

[0006] The technical solution of the present invention is achieved in this way:

[0007] An embodiment of the present invention provides a speed planning method for enhancing the cornering ability of a wheeled robot, comprising: determining the kinematic relationship of the wheeled robot when cornering based on an inverse kinematic model of the chassis of a differential motion robot; calculating based on the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion; calculating based on a preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel, wherein, based on the line curvature and the speed acceleration and deceleration constraints of the inner and outer wheels, the vehicle body kinematic constraints are constrained, and when the outer wheel constraint is selected as a constant speed of the outer wheel, a one-to-one mapped solution of the inner wheel speed is obtained.

[0008] Optionally, the kinematic relationship includes: when the preset curvature is not equal to 0, it is determined that the wheeled robot triggers a turn, and the turning radius of the outer wheel of the wheeled robot is greater than the turning radius of the inner wheel of the wheeled robot; if the wheeled robot is controlled to remain consistent as a whole, the speed of the inner wheel is adjusted, wherein the outer wheel, the inner wheel, the center of motion, the preset curvature and the wheel spacing satisfy a first preset mathematical relationship.

[0009] Further, optionally, the chassis inverse kinematics model of the differential motion robot includes:

[0010]

[0011] Among them, when the preset curvature is greater than 0, v l is the speed of the inner wheel, v r is the speed of the outer wheel. When the preset curvature is less than 0, v l is the speed of the outer wheel, v r is the speed of the inner wheel, v x is the speed of the center of motion, ω is the angle of the center of motion, and W is the wheel spacing;

[0012] The preset curvature has a second preset mathematical relationship with the speed of the center of motion and the angle of the center of motion;

[0013] The second preset mathematical relationship includes:

[0014]

[0015] Wherein, k is the preset curvature.

[0016] Optionally, the first preset mathematical relationship includes:

[0017]

[0018] Wherein, the first preset mathematical relationship is obtained by performing calculation based on the chassis inverse kinematics model of the differential motion robot and the second preset mathematical relationship.

[0019] Optionally, calculating according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion includes: calculating according to a first preset mathematical relationship in the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion.

[0020] Further, optionally, the speed of the motion center is:

[0021]

[0022] Optionally, calculating based on a preset curvature, the physical properties of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel includes: calculating based on a first preset mathematical relationship in combination with a preset curvature, the physical properties of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel.

[0023] Further, optionally, the speed of the inner wheel is:

[0024]

[0025] The speed of the outer wheel is:

[0026]

[0027] An embodiment of the present invention provides a speed planning device for enhancing the cornering ability of a wheeled robot, comprising: an acquisition module, used to determine the kinematic relationship of the wheeled robot when cornering according to the chassis inverse kinematic model of the differential motion robot; a first calculation module, used to calculate according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion; a second calculation module, used to calculate according to the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel, wherein the vehicle body kinematic constraints are constrained according to the line curvature and the speed acceleration and deceleration constraints of the inner and outer wheels, and when the outer wheel constraint is selected as the outer wheel constant speed, a one-to-one mapped solution of the inner wheel speed is obtained.

[0028] An embodiment of the present invention provides a wheeled robot, comprising: a speed planning device for enhancing the cornering ability of the wheeled robot.

[0029] The embodiments of the present invention provide a speed planning method, device and wheeled robot for enhancing the cornering ability of a wheeled robot. The kinematic relationship of the wheeled robot when cornering is determined based on the chassis inverse kinematics model of the differential motion robot; the speed of the center of motion is calculated based on the kinematic relationship and the physical characteristics of the outer wheel; the speed of the inner wheel is calculated based on the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion, thereby improving the control performance and adaptability of the wheeled robot and realizing the technical effect of speed planning of the wheeled robot during movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0031] Figure 1 A schematic flow chart of a speed planning method for enhancing the cornering capability of a wheeled robot provided by an embodiment of the present invention;

[0032] Figure 2 A schematic diagram of a wheeled robot turning in a speed planning method for enhancing the turning ability of a wheeled robot provided by an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of a route of a differential vehicle in the related art;

[0034] Figure 4 is a differential wheel speed diagram of a differential vehicle in the related art;

[0035] Figure 5 A schematic diagram of a route of a differential vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention;

[0036] Figure 6 A differential wheel speed diagram of a differential vehicle in a speed planning method for enhancing the cornering capability of a wheeled robot provided in an embodiment of the present invention;

[0037] Figure 7 A schematic diagram of a route of a dual-steering wheel vehicle in the related art;

[0038] Figure 8 It is a diagram of steering wheel speed and steering angle of a dual-steering wheel vehicle in the related art;

[0039] Fig. 9 A schematic diagram of a route of a dual-steering wheel vehicle in a speed planning method for enhancing the cornering capability of a wheeled robot provided by an embodiment of the present invention;

[0040] Fig.10 A steering wheel speed diagram and a steering angle diagram of a dual-steering wheel vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided in an embodiment of the present invention;

[0041] Fig.11 A schematic diagram of a speed planning device for enhancing the cornering capability of a wheeled robot provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first", "second" and the like in the specification, claims and drawings of the present invention are used to distinguish different objects rather than to limit a specific order.

[0044] It should also be noted that the following embodiments of the present invention may be executed separately, or in combination with each other, and the embodiments of the present invention do not impose any specific limitations on this.

[0045] An embodiment of the present invention provides a speed planning method for enhancing the cornering ability of a wheeled robot. Figure 1 A schematic flow chart of a speed planning method for enhancing the cornering capability of a wheeled robot provided by an embodiment of the present invention; Figure 1 As shown, the speed planning method for enhancing the cornering ability of a wheeled robot provided in an embodiment of the present application includes:

[0046] Step S100, determining the kinematic relationship of the wheeled robot when turning according to the chassis inverse kinematics model of the differential motion robot;

[0047] Optionally, the kinematic relationship includes: when the preset curvature is not equal to 0, it is determined that the wheeled robot triggers a turn, and the turning radius of the outer wheel of the wheeled robot is greater than the turning radius of the inner wheel of the wheeled robot; if the wheeled robot is controlled to remain consistent as a whole, the speed of the inner wheel is adjusted, wherein the outer wheel, the inner wheel, the center of motion, the preset curvature and the wheel spacing satisfy a first preset mathematical relationship.

[0048] Further, optionally, the chassis inverse kinematics model of the differential motion robot includes:

[0049]

[0050] Among them, when the preset curvature is greater than 0, v l is the speed of the inner wheel, v r is the speed of the outer wheel; when the preset curvature is less than 0, v l is the speed of the outer wheel, v r is the speed of the inner wheel, v x is the speed of the center of motion, ω is the angle of the center of motion, and W is the wheel spacing;

[0051] The preset curvature has a second preset mathematical relationship with the speed of the center of motion and the angle of the center of motion;

[0052] The second preset mathematical relationship includes:

[0053]

[0054] Wherein, k is the preset curvature.

[0055] Optionally, the first preset mathematical relationship includes:

[0056]

[0057] Wherein, the first preset mathematical relationship is obtained by performing calculation based on the chassis inverse kinematics model of the differential motion robot and the second preset mathematical relationship.

[0058] Specifically, the speed planning method for enhancing the cornering ability of a wheeled robot provided in the embodiment of the present application uses the inverse kinematics model of a differential motion robot to analyze the kinematic relationship of the wheeled robot when cornering, and establishes the relationship between the wheel speed (inner wheel and outer wheel) and the speed of the motion center and the angular velocity of the motion center. Among them, by analyzing the relationship between curvature and wheel speed, the reason for the difference in speed between the inner and outer wheels when cornering is clarified, that is, when k>0, that is, when the wheeled robot turns, the speed of the inner wheel is less than the speed of the outer wheel. This is because the turning radius of the outer wheel is larger at this time. If you want to maintain overall consistency, you must meet the kinematic constraint requirements. Therefore, if you keep the speed of the outer wheel constant, you need to adjust the speed of the inner wheel, that is, reduce the speed of the inner wheel.

[0059] When the wheeled robot's travel path and curvature are preset, the cornering performance cannot be improved by changing the curvature, but the maximum actuator speed can be constrained to avoid exceeding its capacity.

[0060] Specifically, Figure 2 Schematic diagram of a wheeled robot turning in a speed planning method for enhancing the turning ability of a wheeled robot provided in an embodiment of the present invention. In the embodiment of the present application, the differential motion robot is as follows Figure 2 As shown in the figure, when the differential car with a wheel spacing of W passes a curve, the turning radius is R, and the speed of the outer wheel is greater than that of the inner wheel. If the speed of the outer wheel of the wheeled robot is controlled to be constant, the speed of the center of motion and the speed of the inner wheel will both be reduced.

[0061] Step S102, calculating according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the motion center;

[0062] Optionally, in step S102, calculating according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion includes: calculating according to a first preset mathematical relationship in the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion.

[0063] Further, optionally, the speed of the motion center is:

[0064]

[0065] Specifically, due to the kinematic relationship in step S100, an inverse operation is performed according to the first preset mathematical relationship in the kinematic relationship (an inverse operation is performed according to formula (5)), the speed of the motion center is obtained, and the speed of the motion center when turning is inversely calculated to ensure that the wheeled robot can operate stably under different curvatures. And by considering the curvature of the curve, the speed of the motion center is adaptively adjusted to cope with the challenges brought by the change of curvature.

[0066] Step S104, calculating according to the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel, wherein according to the curvature of the line and the acceleration and deceleration constraints of the inner and outer wheels, the vehicle body kinematic constraints are constrained, and when the outer wheel constraint is selected as the outer wheel constant speed, a one-to-one mapping solution of the inner wheel speed is obtained;

[0067] Optionally, in step S104, calculating based on a preset curvature, the physical properties of the outer wheel and the speed of the motion center to obtain the speed of the inner wheel includes: calculating based on a first preset mathematical relationship in combination with a preset curvature, the physical properties of the outer wheel and the speed of the motion center to obtain the speed of the inner wheel.

[0068] Further, optionally, the speed of the inner wheel is:

[0069]

[0070] The speed of the outer wheel is:

[0071]

[0072] Specifically, the speed of the motion center is recalculated according to the speed of the outer wheel, and the speed of the inner wheel is adjusted accordingly to maintain the stability of the wheeled robot.

[0073] Step S108, adjusting the inner wheel according to the speed of the inner wheel.

[0074] In one achievable manner, when the wheeled robot is a differential motion robot, the kinematic constraints of the differential chassis motor are as follows: The left and right motors of the differential motion robot serve as actuators, and the maximum speed of each motor is v max , the maximum acceleration of each motor is a max The inverse kinematics model of the chassis is:

[0075]

[0076] Where W is the wheel spacing, v x is the longitudinal velocity of the center of motion, which is the velocity in the direction of travel; ω is the angular velocity of the center of motion. l is the left wheel speed in the direction of travel, v r is the right wheel speed in the direction of travel.

[0077] Consider curvature Then the above (9)(10) becomes

[0078]

[0079] When k>0, that is, when the differential motion robot rotates counterclockwise, v l <v r , that is, when the differential motion robot turns left, the speed of the left wheel will be lower than that of the right wheel. This is because the turning radius of the right wheel is larger at this time. In order to maintain overall consistency, the kinematic constraints must be met. When k<0, the situation is symmetrical.

[0080] In the process of steering the differential motion robot, the turning radius of the inner wheel is always smaller than that of the outer wheel, so if the center speed v is maintained x Constant, must be the inner wheel speed ratio v x Small, and the outer wheel speed is faster than v x The curvature change trend will be reflected in the speed change, because

[0081]

[0082] This also causes the outer wheel to easily exceed its own acceleration and speed limits when cornering.

[0083] In one achievable manner, when the wheeled robot is a differential vehicle, the constraint on the constant speed of the outer wheels of the differential vehicle when turning is specifically as follows:

[0084] For the operation conditions of AGV (Automated Guided Vehicle) and AMR (Autonomous Mobile Robot), all operation routes and curvatures are preset, so the cornering performance cannot be improved by changing the curvature, but the maximum actuator speed can be constrained to meet v max and acceleration a max to avoid exceeding its capabilities.

[0085] Obviously, according to the above kinematic analysis, when turning, no matter the curvature is positive or negative, the outer wheel has the highest speed, so the outer wheel is the fastest ... x Constant cornering becomes keeping the outside wheel speed constant.

[0086] According to kinematics, the outer wheel v o Start from the reverse direction to get the motion center speed v that needs to be planned x ;

[0087]

[0088] This situation is the same whether the outer wheel is the left wheel or the right wheel.

[0089] For example, when k>0, the speeds of the left and right wheels when turning are

[0090]

[0091] k<0 Similarly, the maximum speed of the outer wheel will never exceed v max .

[0092] At the same time, if the curvature change rate of a curve If the amplitude is too large, the acceleration of the motor of one wheel of the differential car may exceed a max , resulting in the constraint not being satisfied.

[0093] When the right wheel is the outer wheel, maintain a constant speed v o When the left wheel speed changes, it is

[0094]

[0095] Take the derivative and convert it into the differential with respect to the position s

[0096]

[0097] After obtaining the absolute value, the maximum acceleration of the left wheel is a max When satisfied, there will be

[0098]

[0099] Obviously, the same is true when the right wheel is the outer wheel, so the maximum acceleration a can be obtained. max There should be outer wheel speed under the limit

[0100]

[0101] In summary, the differential car chassis has two constraints:

[0102]

[0103]

[0104] So the velocity of the center of mass v x Using these two constraints during planning can ensure that the outer wheel speed of the differential vehicle reaches the maximum when passing a curve, and the acceleration and deceleration process will not violate the kinematic constraints.

[0105] Specifically, the differential car example is as follows: a differential car with a wheel spacing of 0.58m and a maximum wheel speed of 1.5m / s;

[0106] Related technologies such as Figure 3 As shown, Figure 3 This is a schematic diagram of the route of the differential car in the related art, where plan pose is the reference route of the car body and curpose is the actual track of the car body. It can be seen that the differential car runs directly through a curve at a speed of 1.5m / s, and ends up going out of the reference route on the curve. (The arrows in the middle indicate the direction of the car body);

[0107] based on Figure 3 , Figure 4 is the differential wheel speed diagram of the differential vehicle in the related art, such as Figure 4 As shown in the differential wheel speed diagram, cmd v l , cmd v r Respectively represent the left and right wheel speeds issued, feedback v l ,feedback r Respectively represent the feedback speed of the left and right wheels. Note that when entering this left turn, the speed required by the right wheel is very high, and the feedback speed cannot be executed.

[0108] Figure 5 A schematic diagram of a route of a differential vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention, such as Figure 5 As shown, in the embodiment of the present application, plan pose is the reference route of the vehicle body, and curpose is the actual track of the vehicle body. After adopting this method, the differential vehicle adaptively slows down on the curve, passes the curve normally, and stably follows the reference route. (The arrows on the way indicate the direction of the vehicle body);

[0109] Figure 6 A differential wheel speed diagram of a differential vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention, such as Figure 6 As shown in the differential wheel speed diagram, cmd v l , cmd v r Respectively represent the left and right wheel speeds issued, feedback v l ,feedback r Respectively represent the feedback speed of the left and right wheels. Note that when entering this left turn, the right wheel slows down to about 1.2m / s and remains basically unchanged, while the left wheel continues to slow down to provide the required angular velocity, and the feedback speed responds normally.

[0110] In one achievable manner, when the wheeled robot is a forklift, the constraint on the constant speed of the outer wheels when the forklift turns is specifically as follows:

[0111] The forklift robot with a central steering wheel has only one front steering wheel, i.e., the outer wheel. Its chassis inverse kinematics model is:

[0112]

[0113] The wheelbase is L. Considering the curvature relationship, it is

[0114]

[0115] The kinematics of the forklift is based on the rudder angle δ, given by

[0116]

[0117] The actual cornering ability depends on the rate of change of the rudder angle when cornering. The maximum rudder speed is Then there is

[0118] L k =sec 2 (δ)dδ

[0119] The relationship between the time rate of change is obtained by the distance s of the line, so we have

[0120]

[0121] Therefore, under the constant speed model, the allowable wheel speed constraint when cornering is actually

[0122]

[0123] In one achievable manner, when the wheeled robot is a symmetrically arranged steering wheel vehicle, the constraints based on the symmetrically arranged steering wheel vehicle model are specifically as follows:

[0124] Based on the derivation of the forklift constraints above, it is not difficult to obtain the general formula for the chassis of a generally symmetrical steering wheel vehicle (including dual steering wheels and quad steering wheel vehicles) without considering the lateral speed:

[0125]

[0126] Where W is the wheel spacing and L is the wheelbase.

[0127] Related technologies such as Figure 7 As shown, Figure 7 This is a schematic diagram of the route of a dual-steering wheel vehicle in the related art, where planpose is the reference route of the vehicle body and curpose is the actual track of the vehicle body. The dual-steering wheel vehicle does not adopt this solution and directly runs through the curve at a speed of 1m / s; as a result, it drives out of the reference route on the curve. (The arrows in the middle indicate the direction of the vehicle body)

[0128] Related technologies such as Figure 8 As shown, Figure 8 The figure shows the steering wheel speed diagram and steering angle diagram of a dual-steering wheel vehicle in the related art. In the steering wheel speed diagram, cmd vf and cmd vr represent the issued front and rear wheel speeds, respectively, and feedback vf and feedback vr represent the fed-back front and rear wheel speeds, respectively. It is noted that when entering a curve, the issued speeds of the front and rear wheels need to be very large, and the feedback speed cannot be executed.

[0129] Steering wheel speed diagram, cmd fsteer, cmd rsteer represent the issued front and rear wheel steering angles respectively, feedbackfsteer, feedback rsteer represent the fedback front and rear wheel steering angles respectively. When entering a curve, the issued front and rear wheel steering angles need to change very quickly, and the feedback steering angle cannot be executed.

[0130] Fig. 9 A schematic diagram of a route of a dual-steering wheel vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention, such as Fig. 9 As shown in the figure, the dual-steering wheel vehicle adopts this solution and initially runs through the curve at a speed of 1m / s. As a result, after adaptively slowing down on the curve, it passes the curve normally and stably follows the reference line. (The arrows in the middle indicate the direction of the vehicle body)

[0131] Fig.10 The steering wheel speed diagram and steering angle diagram of a dual-steering wheel vehicle in a speed planning method for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention are as follows: Fig.10 As shown in the figure, in the steering wheel speed diagram, cmd vf and cmd vr represent the issued front and rear wheel speeds, respectively, and feedback vf and feedback vr represent the fed-back front and rear wheel speeds, respectively. Note that when entering a curve, the issued speeds of the front and rear wheels do not change much, and the feedback speed can be easily executed. In the steering angle diagram, cmd fsteer and cmd rsteer represent the issued front and rear wheel steering angles, respectively, and feedback fsteer and feedback rsteer represent the fed-back front and rear wheel steering angles, respectively. When entering a curve, the issued steering angles of the front and rear wheels change within the expected range, and the feedback steering angle is executed normally.

[0132] The speed planning method for enhancing the cornering ability of a wheeled robot provided in the embodiment of the present application fully considers the actual ability of the actuator during speed planning, avoiding the problem of the end effector being unable to be realized due to unreasonable speed instructions. Through the innovation of algorithm logic, precise control of the speed of the wheeled robot when cornering is achieved, improving the stability and cornering ability of the wheeled robot. Using the differential car model, it is demonstrated how to adjust the speed of the center of motion and the speed of the inner wheel at different turning radii.

[0133] An embodiment of the present invention provides a speed planning method for enhancing the cornering ability of a wheeled robot. The kinematic relationship of the wheeled robot when cornering is determined based on the chassis inverse kinematic model of the differential motion robot; the speed of the center of motion is calculated based on the kinematic relationship and the physical characteristics of the outer wheel; the speed of the inner wheel is calculated based on the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion, thereby improving the control performance and adaptability of the wheeled robot and achieving the technical effect of speed planning of the wheeled robot during movement.

[0134] An embodiment of the present invention provides a speed planning device for enhancing the cornering ability of a wheeled robot. Fig.11 A schematic diagram of a speed planning device for enhancing the cornering ability of a wheeled robot provided by an embodiment of the present invention is shown in FIG. Fig.11 As shown, the speed planning device for enhancing the cornering ability of a wheeled robot provided in an embodiment of the present application includes: an acquisition module 110, used to determine the kinematic relationship of the wheeled robot when cornering according to the chassis inverse kinematic model of the differential motion robot; a first calculation module 112, used to calculate according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion; a second calculation module 114, used to calculate according to the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion to obtain the speed of the inner wheel, wherein the vehicle body kinematic constraints are constrained according to the line curvature and the speed acceleration and deceleration constraints of the inner and outer wheels, and when the outer wheel constraint is selected as the outer wheel constant speed, a one-to-one mapped solution of the inner wheel speed is obtained.

[0135] An embodiment of the present invention provides a speed planning device for enhancing the cornering ability of a wheeled robot. The kinematic relationship of the wheeled robot when cornering is determined based on the chassis inverse kinematic model of the differential motion robot; the speed of the center of motion is calculated based on the kinematic relationship and the physical characteristics of the outer wheel; the speed of the inner wheel is calculated based on the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion, thereby achieving the technical effect of improving the control performance and adaptability of the wheeled robot.

[0136] An embodiment of the present invention provides a wheeled robot, comprising: Figure 3 The speed planning device shown has enhanced cornering capability of a wheeled robot.

[0137] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention.

Claims

1. A speed planning method for enhancing the cornering ability of a wheeled robot, characterized in that: include: According to the chassis inverse kinematics model of the differential motion robot, the kinematic relationship of the wheeled robot when turning is determined; Calculating according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion; The speed of the inner wheel is calculated according to the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion, wherein the kinematic constraints of the vehicle body are constrained according to the line curvature and the speed acceleration and deceleration constraints of the inner and outer wheels. When the outer wheel constraint is selected as the outer wheel constant speed, a one-to-one mapping solution of the inner wheel speed is obtained.

2. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 1, characterized in that: The kinematic relationships include: When the preset curvature is not equal to 0, it is determined that the wheeled robot has triggered a turn, and the turning radius of the outer wheel of the wheeled robot is greater than the turning radius of the inner wheel of the wheeled robot. If the wheeled robot is controlled to remain consistent as a whole, the speed of the inner wheel is adjusted, wherein the outer wheel, the inner wheel, the motion center, the preset curvature and the wheel spacing satisfy a first preset mathematical relationship.

3. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 2, characterized in that: The chassis inverse kinematics model of the differential motion robot includes: Among them, when the preset curvature is greater than 0, v l is the speed of the inner wheel, v r is the speed of the outer wheel; when the preset curvature is less than 0, v l is the speed of the outer wheel, v r is the speed of the inner wheel, v x is the speed of the motion center, ω is the angle of the motion center, and W is the wheel spacing; There is a second preset mathematical relationship between the preset curvature, the speed of the motion center, and the angle of the motion center; The second preset mathematical relationship includes: Wherein, k is the preset curvature.

4. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 3, characterized in that: The first preset mathematical relationship includes: Wherein, the first preset mathematical relationship is obtained by performing calculation based on the chassis inverse kinematics model of the differential motion robot and the second preset mathematical relationship.

5. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 4, characterized in that: The calculation based on the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the center of motion includes: The speed of the center of motion is obtained by performing calculations based on the first preset mathematical relationship in the kinematic relationship and the physical characteristics of the outer wheel.

6. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 5, characterized in that: The velocity of the center of motion is:

7. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 6, characterized in that: The calculation based on the preset curvature, the physical characteristics of the outer wheel and the speed of the motion center to obtain the speed of the inner wheel includes: The speed of the inner wheel is obtained by performing calculation according to the first preset mathematical relationship in combination with the preset curvature, the physical characteristics of the outer wheel and the speed of the motion center.

8. The speed planning method for enhancing the cornering ability of a wheeled robot according to claim 7, characterized in that: The speed of the inner wheel is: The speed of the outer wheel is:

9. A speed planning device for enhancing the cornering ability of a wheeled robot, characterized in that: include: An acquisition module is used to determine the kinematic relationship of the wheeled robot when turning according to the chassis inverse kinematics model of the differential motion robot; A first calculation module, configured to calculate according to the kinematic relationship and the physical characteristics of the outer wheel to obtain the speed of the motion center; The second calculation module is used to calculate the speed of the inner wheel according to the preset curvature, the physical characteristics of the outer wheel and the speed of the center of motion, wherein the kinematic constraints of the vehicle body are constrained according to the line curvature and the speed acceleration and deceleration constraints of the inner and outer wheels, and when the outer wheel constraint is selected as the outer wheel constant speed, a one-to-one mapping solution of the inner wheel speed is obtained.

10. A wheeled robot, characterized in that: include: The speed planning device for enhancing the cornering ability of a wheeled robot as described in claim 9.

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