A hybrid steering chassis system device for an all-terrain vehicle

Abstract

The invention relates to the technical field of transportation equipment, and in particular to an all-terrain vehicle hybrid steering chassis system device; the device comprises a differential steering subsystem, an Ackerman steering subsystem, a suspension subsystem and a control subsystem, wherein the differential steering subsystem is connected to the suspension subsystem via a spline to realize power transmission of a wheel on one side, the Ackerman steering subsystem is connected to the suspension subsystem via a ball head to realize different required turning angles of the wheels on the left and right sides, and the control subsystem controls the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem, and takes the yaw angle of the whole vehicle as the control target. The system effectively improves the handling stability and smoothness of the whole vehicle at high speed, and also has the characteristics of zero-radius steering, high load-bearing capacity, strong off-road, easy control, reliable performance and low cost, and solves the problems of large turning radius and poor vehicle passability of the existing all-terrain vehicle steering system.

Description

Technical Field

[0001] The invention relates to the technical field of transportation equipment, and in particular to a hybrid steering chassis system device for an all-terrain vehicle. Background Art

[0002] All-terrain vehicles are simple and practical, with good off-road performance. They are non-road vehicles that can be used on a variety of complex roads and can be used to carry out personnel mobility, equipment and material transportation in special geographical conditions such as mountains, jungles, beaches, deserts and snowy areas.

[0003] In the current design of all-terrain vehicles, most vehicles use the Ackerman steering system, which is similar to that of ordinary passenger vehicles. The turning radius of the vehicle is large and the vehicle's passability is poor. With the rapid growth of the all-terrain vehicle industry, customers have put forward higher requirements for vehicle off-road performance, load-bearing capacity, and handling stability. Existing technical solutions can no longer meet customer needs. Summary of the invention

[0004] The purpose of the present invention is to provide an all-terrain vehicle hybrid steering chassis system device, aiming to solve the problems of large turning radius and poor vehicle trafficability of the existing all-terrain vehicle steering system.

[0005] To achieve the above-mentioned objectives, the present invention provides an all-terrain vehicle hybrid steering chassis system device, comprising a differential steering subsystem, an Ackerman steering subsystem, a suspension subsystem and a control subsystem, wherein the differential steering subsystem is connected to the suspension subsystem and is located on one side of the suspension subsystem, the Ackerman steering subsystem is connected to the suspension subsystem and is located on both sides of the suspension subsystem, and the control subsystem is respectively connected to the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem.

[0006] Wherein, the suspension subsystem includes a front suspension double wishbone module and a rear suspension double wishbone module.

[0007] The Ackerman steering subsystem includes a single-axis Ackerman steering module and a double-axis Ackerman steering module. The single-axis Ackerman steering module is connected to the front suspension double wishbone module, and the double-axis Ackerman steering module is connected to the rear suspension double wishbone module.

[0008] Among them, the differential steering subsystem includes a left wheel transmission module and a right wheel transmission module, the left wheel transmission module is connected to the front suspension double wishbone module, and the right wheel transmission module is arranged on one side of the left wheel transmission module.

[0009] Wherein, the control subsystem is connected to the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem via a CAN bus.

[0010] The present invention discloses a hybrid steering chassis system device for an all-terrain vehicle, wherein the differential steering subsystem is connected to the suspension subsystem via a spline to realize power transmission of a wheel on one side, the Ackerman steering subsystem is connected to the suspension subsystem via a ball head to realize different required turning angles of the left and right wheels, the control subsystem controls the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem, and takes the yaw angle of the whole vehicle as the control target. The system effectively improves the handling stability and smoothness of the whole vehicle at high speed, and also has the characteristics of zero-radius steering, high load-bearing capacity, strong off-road, easy control, reliable performance and low cost, thereby solving the problems of large turning radius and poor vehicle passability of the existing all-terrain vehicle steering system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 The present invention is a schematic structural diagram of a hybrid steering chassis system device for an all-terrain vehicle.

[0013] Figure 2 It is a schematic diagram of the suspension subsystem structure.

[0014] Figure 3 It is a schematic diagram of the structure of the Ackerman steering subsystem.

[0015] Figure 4 It is a schematic diagram of the differential steering subsystem structure.

[0016] Figure 5 The invention is a connection diagram of a hybrid steering chassis system device for an all-terrain vehicle.

[0017] Figure 6 It is the assembly structure diagram of the suspension subsystem and transmission system.

[0018] Figure 7 It is the assembly structure diagram of the suspension subsystem and the Ackerman steering subsystem.

[0019] In the figure: 1-differential steering subsystem, 2-Ackerman steering subsystem, 3-suspension subsystem, 4-control subsystem, 5-front suspension double wishbone module, 6-rear suspension double wishbone module, 7-one-axis Ackerman steering module, 8-two-axis Ackerman steering module, 9-left wheel transmission module, 10-right wheel transmission module. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0021] See also Figures 1 to 7 The present invention provides an all-terrain vehicle hybrid steering chassis system device, including a differential steering subsystem 1, an Ackerman steering subsystem 2, a suspension subsystem 3 and a control subsystem 4, wherein the differential steering subsystem 1 is connected to the suspension subsystem 3 and is located on one side of the suspension subsystem 3, the Ackerman steering subsystem 2 is connected to the suspension subsystem 3 and is located on both sides of the suspension subsystem 3, and the control subsystem 4 is respectively connected to the differential steering subsystem 1, the Ackerman steering subsystem 2 and the suspension subsystem 3.

[0022] In this embodiment, the differential steering subsystem 1 is connected to the suspension subsystem 3 through a spline to achieve power transmission of a single-side wheel. The Ackerman steering subsystem 2 is connected to the suspension subsystem 3 through a ball head to achieve different required turning angles of the left and right wheels. The control subsystem 4 controls the differential steering subsystem 1, the Ackerman steering subsystem 2 and the suspension subsystem 3, with the yaw angle of the whole vehicle as the control target. The system effectively improves the handling stability and smoothness of the whole vehicle at high speed, and also has the characteristics of zero-radius steering, high load-bearing capacity, strong off-road, easy control, reliable performance and low cost, which solves the problem of large turning radius and poor vehicle passability of the existing all-terrain vehicle steering system.

[0023] Furthermore, the suspension subsystem 3 includes a front suspension double wishbone module 5 and a rear suspension double wishbone module 6 .

[0024] In this embodiment, the front suspension double wishbone module 5 is consistent with the rear suspension double wishbone module 6. The suspension subsystem 3 has a simple structure and low manufacturing cost. It is connected to the vehicle body by bolts, which is convenient for mass production. Figure 2 .

[0025] Furthermore, the Ackerman steering subsystem 2 includes a single-axis Ackerman steering module 7 and a dual-axis Ackerman steering module 8 , wherein the single-axis Ackerman steering module 7 is connected to the front suspension double wishbone module 5 , and the dual-axis Ackerman steering module 8 is connected to the rear suspension double wishbone module 6 .

[0026] In this embodiment, the one-axis Ackerman steering module 7 and the two-axis Ackerman steering module 8 have no mechanical connection, and information exchange is performed through the bus, so that different wheel steering angles can be achieved, and the steering gear adopts a rack and pinion steering gear, which has a simple structure, low manufacturing cost, and is convenient for mass production. Figure 3 .

[0027] Furthermore, the differential steering subsystem 1 includes a left wheel transmission module 9 and a right wheel transmission module 10 , the left wheel transmission module 9 is connected to the front suspension double wishbone module 5 , and the right wheel transmission module 10 is arranged on one side of the left wheel transmission module 9 .

[0028] In this embodiment, there is no mechanical connection between the left wheel transmission module 9 and the right wheel transmission module 10, which can realize the differential function of the left and right wheels, and also realize the zero radius steering of the chassis, with a simple structure, reliable performance and convenient mass production. Figure 4 .

[0029] Furthermore, the control subsystem 4 is connected to the differential steering subsystem 1, the Ackerman steering subsystem 2 and the suspension subsystem 3 via a CAN bus.

[0030] In this embodiment, the control subsystem 4 takes the yaw angle of the vehicle as the control target to control the steering of the vehicle. The control method is simple, the performance is reliable, and it is easy to mass produce. Figure 5 .

[0031] The present invention provides a hybrid steering chassis system device for an all-terrain vehicle, wherein the control subsystem 4 independently controls the differential steering subsystem 1, thereby controlling the wheel speed difference of the wheels on both sides. When the output rotation speeds of the left wheel transmission module 9 and the right wheel transmission module 10 are equal in magnitude and opposite in direction, zero radius steering can be achieved; the control subsystem 4 controls the outputs of the left wheel transmission module 9 and the right wheel transmission module 10, and when the left wheel speed is greater than the right wheel speed, the whole vehicle turns right, and when the left wheel speed is less than the right wheel speed, the whole vehicle turns left.

[0032] When the control subsystem 4 independently controls the Ackerman steering subsystem 2, the steering command is sent to the Ackerman steering subsystem 2 through the bus to control the movement stroke and direction of the rack and pinion steering gear to realize the left and right steering function of the whole vehicle.

[0033] The control theory is as follows:

[0034] The control subsystem 4 is responsible for: receiving requests for vehicle speed and steering curvature, the left and right motor speeds reported by the differential steering subsystem, and the Ackerman steering system reporting the current steering angles of the one-axis Ackerman steering module 7 and the two-axis Ackerman steering module 8; collecting the current actual yaw angular velocity of the vehicle; calculating the required steering angles of the one-axis and two-axis Ackerman steering module 8 and the two-axis Ackerman steering module 8, and sending them to the Ackerman steering subsystem 2; calculating the required driving torque of the left and right motors and sending them to the differential steering subsystem 1.

[0035] The Ackerman steering subsystem 2 is responsible for: receiving the steering angles of the one-axis Ackerman steering module 7 and the two-axis Ackerman steering module 8 required by the control subsystem 4, and controlling the steering mechanisms of the one-axis and two-axis Ackerman steering modules 8 and the two-axis Ackerman steering modules 8 to operate to the required one-axis and two-axis steering angles, and reporting the current steering angles of the one-axis Ackerman steering module 7 and the two-axis Ackerman steering module 8.

[0036] The differential steering subsystem 1 is responsible for: receiving the driving torque of the left and right motors required by the control subsystem 4, controlling the left and right motors to output the required torque, and reporting the speed, torque and other information of the left and right motors.

[0037] The specific control methods are as follows:

[0038] Calculation of driving torque of differential system

[0039] The differential system driving torque T consists of two parts: the straight driving torque Ta and the steering torque Tturn.

[0040] Tl=Ta+Tturn

[0041] Tr=Ta+Tturn

[0042] Calculation of the straight driving torque Ta: The control subsystem 4 calculates the straight driving torque Ta by using the PI control method according to the vehicle speed request Vref and the current vehicle speed Vact.

[0043] Ta=Kp*(Vref-Vact)+Ki*∫(Vref-Vact)dt

[0044] Where Kp and Ki are calibration parameters.

[0045] Calculation of steering torque Tturn. The control subsystem 4 calculates the target wheel speed difference on both sides through PI control according to the request of steering curvature and the current actual yaw rate, and then calculates the motor speed difference on both sides in combination with the vehicle parameters; according to the current motor speed difference on both sides and the actual motor speed difference on both sides, PI control is used again to calculate the motor steering torque.

[0046] ΔR=Kp*(ωref-ωact)+Ki*∫(ωref-ωact)dt

[0047] ΔW=ΔR*Df÷R*iChain

[0048] Tturn=Kp*(ΔWref-ΔWact)+Ki*∫(ΔWref-ΔWact)dt

[0049] In the formula, ΔR is the wheel speed difference, ωref is the target yaw rate, ωact is the actual yaw rate, ΔW is the motor speed difference, Df is the wheelbase, R is the tire radius, iChain is the transmission ratio, ΔWref is the target motor speed difference, and ΔWact is the actual motor speed difference. Kp and Ki are both calibration quantities.

[0050] Calculation of steering angle of Ackerman steering subsystem 2

[0051] The control subsystem 4 outputs the corresponding desired angle of the steering input shaft according to the request of the steering curvature, thereby controlling the front two shafts to perform Ackerman steering. The corresponding relationship between the desired angle of the steering input shaft and the steering radius is as follows:

[0052] The rack travel L1 of the steering gear corresponds to an outer wheel steering angle A1 and a desired angle EPS_Angle of the input shaft.

[0053] The relationship between A1 and turning radius R1 is calculated by the formula:

[0054] R1=2850÷sin(A1*PI / 180)÷1000

[0055] The relationship between L1 and the desired angle EPS_Angle of the steering input shaft is calculated by the formula:

[0056] EPS_Angle=L1÷54.4*360

[0057] Therefore, the steering radius can be matched with the desired angle of the steering gear input shaft, which is beneficial for the control subsystem 4 to output the corresponding desired angle of the steering gear input shaft according to the steering curvature.

[0058] The control subsystem 4 uses the vehicle yaw rate as the control target and the outputs of the differential steering subsystem and the Ackerman steering subsystem 2 as variables to achieve the following functions.

[0059] When the vehicle turns right with differential steering, the output speed of the left wheel transmission module 9 is greater than the output of the right wheel transmission module 10. When the control subsystem 4 detects that the yaw angle of the vehicle becomes larger and the vehicle has an unstable trend, the control subsystem 4 sends a left turn command to the Ackerman steering subsystem 2. After receiving the command from the control subsystem 4, the one-axis Ackerman steering module 7 turns left. After receiving the command from the control subsystem 4, the two-axis Ackerman steering module 8 turns left. The left turn output of the Ackerman steering subsystem 2 makes the vehicle have a left turn trend, thereby offsetting the unstable right turn trend of the differential steering system.

[0060] When the vehicle turns left with differential steering, the output speed of the left wheel transmission module 9 is less than the output of the right wheel transmission module 10, and the control subsystem 4 detects that the yaw angle of the vehicle becomes larger and the vehicle has an unstable trend, the control subsystem 4 sends a steering instruction to the Ackerman steering subsystem 2, and the one-axis Ackerman steering module 7 turns the wheel left after receiving the instruction from the control subsystem 4, and the two-axis Ackerman steering module turns the wheel left after receiving the instruction from the control subsystem 4, and the left turn output of the Ackerman steering subsystem 2 makes the vehicle have a right turn trend, thereby offsetting the right turn unstable trend of the differential steering system;

[0061] When the vehicle turns right with differential steering, the output speed of the left wheel transmission module 9 is greater than the output of the right wheel transmission module 10. When the control subsystem 4 detects that the yaw angle of the vehicle becomes smaller and the vehicle has a tendency to understeer right, the control subsystem 4 sends a steering command to the Ackerman steering subsystem 2. After the one-axis Ackerman steering module 7 receives the command from the control subsystem 4, the wheel turns right. After the two-axis Ackerman steering module 8 receives the command from the control subsystem 4, the wheel turns. The left turn output of the Ackerman steering subsystem 2 makes the vehicle have a turning tendency, thereby improving the understeer tendency of the vehicle right of the differential steering system, so that the vehicle turns right faster.

[0062] When the vehicle turns left with differential steering, the output speed of the left wheel transmission module 9 is less than the output of the right wheel transmission module 10, and the control subsystem 4 detects that the yaw angular acceleration of the vehicle decreases and the vehicle has a tendency to understeer to the left, the control subsystem 4 sends a steering command to the Ackerman steering subsystem 2, and the one-axis Ackerman steering module 7 turns the wheel left after receiving the command from the control subsystem 4, and the two-axis Ackerman steering module 8 turns the wheel after receiving the command from the control subsystem 4, and the left-turn output of the Ackerman steering subsystem 2 makes the vehicle have a turning tendency, thereby improving the understeer tendency of the vehicle to the left of the differential steering system, so that the vehicle turns left more quickly;

[0063] The whole vehicle has a steering redundancy function. When one of the differential drive subsystem and the Ackerman steering subsystem 2 fails, the whole vehicle still has a steering function, which can improve the safety of the whole vehicle; when the Ackerman steering subsystem 2 fails, the differential steering still works, which can ensure the smooth parking of the vehicle. When the differential steering fails, the Ackerman steering subsystem 2 still works, which can also ensure the smooth parking of the vehicle.

[0064] What is disclosed above is only a preferred embodiment of an all-terrain vehicle hybrid steering chassis system device of the present invention. Of course, it cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above-mentioned embodiments and equivalent changes made according to the claims of the present invention are still within the scope of the invention.

Claims

1. A hybrid steering chassis system for an all-terrain vehicle, characterized in that: It includes a differential steering subsystem, an Ackerman steering subsystem, a suspension subsystem and a control subsystem, wherein the differential steering subsystem is connected to the suspension subsystem and is located on one side of the suspension subsystem, the Ackerman steering subsystem is connected to the suspension subsystem and is located on both sides of the suspension subsystem, and the control subsystem is connected to the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem via a CAN bus; The control subsystem controls the differential steering subsystem, the Ackerman steering subsystem and the suspension subsystem, and controls the steering of the whole vehicle by taking the yaw angle of the whole vehicle as the control target; The suspension subsystem includes a front suspension double wishbone module and a rear suspension double wishbone module; The Ackerman steering subsystem includes a one-axis Ackerman steering module and a two-axis Ackerman steering module, wherein the one-axis Ackerman steering module is connected to the front suspension double wishbone module, and the two-axis Ackerman steering module is connected to the rear suspension double wishbone module; The differential steering subsystem includes a left wheel transmission module and a right wheel transmission module, the left wheel transmission module is connected to the front suspension double wishbone module, and the right wheel transmission module is arranged on one side of the left wheel transmission module.

Images