A highly integrated intelligent wheel leg with independent direction-changing and lifting functions

Abstract

The present invention is a highly integrated intelligent wheel leg with independent directional change and lifting functions. The wheel leg includes a lifting system, a walking system, and a wheel leg control system. The lifting system adjusts the wheel leg lifting under the control of the wheel leg control system. The walking system is arranged at the lower end of the lifting system. The walking system performs free steering and normal driving under the control of the wheel leg control system. The wheel leg control system monitors the multi-axis position, angle, length, and linear speed of the wheel leg to determine the current working condition of the wheel leg and perform corresponding emergency control. The wheel leg of the present invention realizes the functions of movement, steering, and lifting. It can be installed by combining multiple wheel legs to quickly complete the design of the mobile platform, making it easier for the vehicle to adapt to complex environments. The mechanical and electrical systems are more integrated, have autonomous control capabilities, and are more adaptable.

Description

Technical Field

[0001] The present invention relates to the technical field of outdoor working robots, and in particular to a highly integrated intelligent wheel leg with independent direction-changing and lifting functions. Background Art

[0002] At present, during the outdoor operation of robot chassis vehicles, chassis with different ground clearances are required according to the scene. To address this problem, the present invention provides a highly integrated intelligent wheel leg with independent directional change and lifting functions. The wheel leg height can be raised and lowered, and the level of the vehicle body can be adjusted in real time to improve the obstacle crossing ability of the wheel leg in complex terrain. At the same time, a function for monitoring wheel slippage is provided to enable it to have high passability, reduce application costs, and have the convenience of adjustable height, which can be applied to a variety of practical scenarios. Summary of the Invention

[0003] The purpose of the present invention is to overcome the problems existing in the prior art and provide a highly integrated intelligent wheel leg with independent direction-changing and lifting functions.

[0004] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0005] A highly integrated intelligent wheel leg with independent directional changing and lifting functions, the wheel leg includes a lifting system, a walking system and a wheel leg control system. The lifting system performs wheel leg lifting and adjustment under the control of the wheel leg control system. The walking system is arranged at the lower end of the lifting system. The walking system performs free steering and normal driving under the control of the wheel leg control system. The wheel leg control system monitors the multi-axis posture, angle, length and linear speed of the wheel leg, and is used to judge the current working condition of the wheel leg and perform corresponding emergency control.

[0006] Furthermore, the lifting system includes a lifting servo motor, a lifting sleeve, a support sleeve, a lifting screw, a rotating bracket and a lifting mounting plate. The lifting mounting plate is fixedly connected to the vehicle frame, the body of the lifting servo motor and the lifting sleeve are fixedly connected to the lifting mounting plate, the output shaft of the lifting servo motor is connected through a coupling and drives the lifting screw to rotate, the lifting screw is rotatably provided with a corresponding screw nut seat and the screw nut seat is fixed in the support sleeve, the outer side of the support sleeve is slidably connected to the lifting sleeve through a linear guide rail, so that the lifting servo motor drives the support sleeve to slide and lift in the lifting sleeve through the lifting screw and the corresponding screw nut seat, and the rotating bracket is fixed to the support sleeve above it.

[0007] Furthermore, the walking system includes a rotary motor, a drive motor, a driving sprocket, a chain, a drive shaft, a driven sprocket, a gyroscope, a wheel, a shell sheet metal and a motor mounting plate. The body of the rotary motor is fixedly connected to the rotary bracket, the gyroscope is horizontally arranged on the shell sheet metal, the motor mounting plate is fixed to the upper part of the shell sheet metal, the drive shaft is located below the motor mounting plate and is rotatably connected to the lower part of the shell sheet metal, the output shaft of the rotary motor is connected through a rotary turntable and drives the shell sheet metal and the motor mounting plate to rotate 360° as a whole, the body of the drive motor is fixed to the motor mounting plate, the output shaft of the drive motor is connected through a corresponding reducer and drives the driving sprocket, the driving sprocket is connected through a chain and drives the driven sprocket to rotate, the wheel axle of the driven sprocket is connected to the drive shaft of the wheel, so that the drive motor drives the wheel to rotate through a chain drive.

[0008] Furthermore, the wheel-leg control system includes a gyroscope, an absolute encoder, a controller, a motor drive, and corresponding lifting servo motors, rotary motors and drive motors. The absolute encoder is arranged at the lifting screw to calculate the vertical displacement of the lifting screw, which is used to estimate the lifting height of the wheel leg and transmit the estimated data to the controller. The gyroscope is used to measure the lateral displacement angle θ1, walking speed v1 and acceleration data of the wheel leg, and transmit the measured data to the controller. The controller is connected to the corresponding host computer through a wireless module, and judges the current working condition of the wheel leg according to the data transmitted by the absolute encoder and the gyroscope, and generates corresponding drive signals to drive the operation of the lifting servo motor, rotary motor and drive motor through the motor drive control to achieve steering, lifting and leveling, driving adjustment and emergency stop protection.

[0009] A control method for a highly integrated intelligent wheel leg with independent direction-changing and lifting functions, the control method including a wheel leg steering control process:

[0010] Step 1.1) Obtaining the actual wheel leg deflection angle: Use a gyroscope as a sensor to measure the wheel leg's lateral displacement angle θ1, which is used to provide wheel leg direction information;

[0011] Step 1.2) Target direction angle acquisition: Output the wheel-leg target direction angle θ2 through the corresponding host computer;

[0012] Step 1.3) PID algorithm outputs control signal: Based on the lateral angle θ1 and the target direction angle θ2, the controller output value is calculated. The controller input is the deviation of the lateral angle θ1, and the output is the control signal used to control the steering.

[0013] Step 1.4) Wheel-leg steering control: Convert the controller's output signal into a wheel-leg steering action, and achieve steering by controlling the slewing motor;

[0014] Step 1.5) Determine whether the steering is in place: Compare the difference △θ between the actual steering angle and the target direction angle θ2 to see whether the steering is in place. If not, measure the lateral angle θ1 again using the gyroscope and repeat step 1.3). If the steering is in place, end the steering control.

[0015] Furthermore, the control method also includes a wheel leg lifting control process:

[0016] Step 2.1) Obtaining the actual vertical displacement offset: Use the absolute encoder to calculate the vertical displacement of the lifting screw to estimate the lifting height of the wheel leg;

[0017] Step 2.2) Obtaining the target vertical displacement offset: Output the target vertical displacement offset of the wheel leg through the corresponding host computer;

[0018] Step 2.3) PID algorithm outputs control signal: Based on PID control, the difference value △x between the actual vertical displacement offset calculated by the absolute encoder and the target vertical displacement offset is used as input, and the control signal for the wheel leg lifting is output;

[0019] Step 2.4) Wheel-leg lift control: The vertical displacement offset is converted to motor speed using the formula N = (Δd / Δt) × (60 / p). This is used to calculate the speed of the lift servo motor and convert the controller output signal into the control signal that drives the lift screw of the lift system.

[0020] Step 2.5) Determine whether the height is adjusted correctly: Compare the difference △x between the actual height adjustment and the target height adjustment to see if the height adjustment is correct. If not, use the absolute value encoder to calculate the vertical displacement offset again and repeat step 2.3). If the steering is correct, the wheel leg lifting control ends.

[0021] Furthermore, the control method also includes a process for monitoring wheel and leg slippage:

[0022] Step 3.1) Obtaining walking speed v1: Obtain acceleration data of the chassis during its movement using the gyroscope. Filter and calibrate the raw acceleration data obtained by the gyroscope to obtain more accurate and stable data. Integrate the processed acceleration data to obtain the speed data of the chassis during its movement.

[0023] Step 3.2) Obtain output speed v2: Obtain the actual linear speed of the wheel by reading the output speed of the drive motor;

[0024] Step 3.3) Calculate the speed difference △v: Compare the walking speed data obtained by the gyroscope with the output speed of the drive motor and calculate the speed difference △v between the two;

[0025] Step 3.4) Slip Detection: Based on the speed difference △v, determine whether the wheel is in a slipping state. If the speed difference exceeds the set threshold, the wheel is determined to be slipping. If the speed difference does not exceed the set threshold, the wheel is determined to be not slipping.

[0026] Step 3.5) Post-feedback measures: Based on the slip detection results, take shutdown protection measures or adjust the vehicle control strategy according to the priority settings to improve the slip problem.

[0027] The beneficial effects of the present invention are:

[0028] The wheel legs of the present invention realize the functions of movement, steering and lifting, and also have autonomous safety adjustment and highly integrated structure and control interface. They can be installed in combination with multiple wheel legs to quickly complete the design of the mobile platform. Steering operations are achieved through the change-direction wheel legs, and they have lifting functions. They can be adjusted under different terrain or height requirements, and at the same time, they can make the vehicle more easily adapt to complex environments. Compared with other types of wheel leg structures, the mechanical and electrical systems are more integrated, have autonomous control capabilities, and are more adaptable. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A perspective view of the wheel-leg lifting system of the present invention;

[0030] Figure 2 A perspective view of the wheel-leg walking system of the present invention;

[0031] Figure 3 This is a hardware block diagram of the control system of the present invention;

[0032] Figure 4 This is a flow chart of the wheel-leg steering control of the present invention;

[0033] Figure 5 This is a flow chart of the wheel leg lifting control of the present invention;

[0034] Figure 6 This is a flow chart of the wheel-leg slip monitoring method of the present invention.

[0035] Explanation of the numbers in the figure: 1. Lifting servo motor, 2. Coupling, 3. Lifting screw, 4. Lifting sleeve, 5. Support sleeve, 6. Linear guide, 7. Rotary bracket, 8. Rotary motor, 9. Drive motor, 10. Driving sprocket, 11. Chain, 12. Drive shaft, 13. Driven sprocket, 14. Gyroscope, 15. Housing sheet metal, 16. Wheel, 17. Motor mounting plate, 18. Lifting mounting plate, 19. Controller. DETAILED DESCRIPTION

[0036] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0037] A highly integrated intelligent wheel leg with independent directional changing and lifting functions, the wheel leg includes a lifting system, a walking system and a wheel leg control system. The lifting system performs wheel leg lifting and adjustment under the control of the wheel leg control system. The walking system is arranged at the lower end of the lifting system. The walking system performs free steering and normal driving under the control of the wheel leg control system. The wheel leg control system monitors the multi-axis posture, angle, length and linear speed of the wheel leg, and is used to judge the current working condition of the wheel leg and perform corresponding emergency control.

[0038] like Figure 1 As shown, the lifting system includes a lifting servo motor 1, a lifting sleeve 4, a support sleeve 5, a lifting screw 3, a rotary bracket 7 and a lifting mounting plate 18. The lifting mounting plate 18 is fixedly connected to the corresponding frame, and the body of the lifting servo motor 1 and the lifting sleeve 4 are fixedly connected to the lifting mounting plate 18. The output shaft of the lifting servo motor 1 is connected through a coupling 2 and drives the lifting screw 3 to rotate. The lifting screw 3 is rotatably provided with a corresponding screw nut seat and the screw nut seat is fixed in the support sleeve 5. The outer side of the support sleeve 5 is slidably connected to the lifting sleeve 4 through a linear guide rail 6, so that the lifting servo motor 1 drives the support sleeve 5 to slide and rise and fall in the lifting sleeve 4 through the lifting screw 3 and the corresponding screw nut seat. The rotary bracket 7 is fixedly connected to the support sleeve 5 above it. In this embodiment, the lower end of the support sleeve 5 is embedded and welded in the rotary bracket 7.

[0039] like Figure 2 As shown, the walking system includes a rotary motor 8, a drive motor 9, a driving sprocket 10, a chain 11, a drive shaft 12, a driven sprocket 13, a gyroscope 14, a wheel 16, a shell sheet metal 15 and a motor mounting plate 17. The body of the rotary motor 8 is fixedly connected to the rotary bracket 7, the gyroscope 14 is horizontally arranged on the shell sheet metal 15, the motor mounting plate 17 is fixed to the upper part of the shell sheet metal 15, the drive shaft 12 is located below the motor mounting plate 17 and is rotatably connected to the lower part of the shell sheet metal 15, and the The output shaft of the rotary motor 8 is connected through the rotary turntable and drives the outer shell sheet metal 15 and the motor mounting plate 17 to rotate 360° as a whole. The body of the drive motor 9 is fixed to the motor mounting plate 17. The output shaft of the drive motor 9 is connected through the corresponding reducer and drives the driving sprocket 10. The driving sprocket 10 is connected through the chain 11 and drives the driven sprocket 13 to rotate. The wheel axle of the driven sprocket 13 is connected to the drive shaft 12 of the wheel 16, so that the drive motor 9 drives the wheel 16 to rotate through chain transmission.

[0040] like Figure 3As shown, the wheel leg control system includes a gyroscope 14, an absolute encoder, a controller 19, a motor drive, and corresponding lifting servo motor 1, rotary motor 8 and drive motor 9. The absolute encoder is arranged at the lifting screw 3 to calculate the vertical displacement of the lifting screw 3, which is used to estimate the lifting height of the wheel leg and transmit the estimated data to the controller 19. The gyroscope 14 is used to measure the lateral displacement angle θ1, walking speed v1 and acceleration data of the wheel leg, and transmit the measured data to the controller 19. The controller 19 is connected to the corresponding host computer through a wireless module, and judges the current working condition of the wheel leg according to the data transmitted by the absolute encoder and the gyroscope 14, and generates a corresponding drive signal to drive the operation of the lifting servo motor 1, rotary motor 8 and drive motor 9 through the motor drive control to achieve steering, lifting and leveling, adjustment of driving and emergency stop protection.

[0041] A control method for a highly integrated intelligent wheel leg with independent direction-changing and lifting functions, such as Figure 4 As shown, the control method includes the wheel leg steering control process:

[0042] Step 1.1) Acquiring the actual wheel leg deflection angle: using the gyroscope 14 as a sensor to measure the lateral displacement angle θ1 of the wheel leg, the lateral displacement angle θ1 is used to provide wheel leg direction information;

[0043] Step 1.2) Target direction angle acquisition: Output the wheel-leg target direction angle θ2 through the corresponding host computer;

[0044] Step 1.3) PID algorithm outputs control signal: Based on the lateral angle θ1 and the target direction angle θ2, the output value of the controller 19 is calculated. The input of the controller 19 is the deviation of the lateral angle θ1, and the output is the control signal used to control the steering;

[0045] Step 1.4) Wheel leg steering control: The output signal of the controller 19 is converted into the steering action of the wheel leg, and the steering is achieved by controlling the rotary motor 8;

[0046] Step 1.5) Determine whether the steering is in place: By comparing the difference value △θ between the actual steering angle and the target direction angle θ2, check whether the steering is in place. If not, measure the lateral angle θ1 again through the gyroscope 14 and repeat step 1.3). If the steering is in place, the steering control ends.

[0047] like Figure 5 As shown, the control method also includes a wheel leg lifting control process:

[0048] Step 2.1) Obtaining the actual vertical displacement offset: Use the absolute encoder to calculate the vertical displacement of the lifting screw 3 to estimate the lifting height of the wheel leg;

[0049] Step 2.2) Obtaining the target vertical displacement offset: Output the target vertical displacement offset of the wheel leg through the corresponding host computer;

[0050] Step 2.3) PID algorithm outputs control signal: Based on PID control, the difference value △x between the actual vertical displacement offset calculated by the absolute encoder and the target vertical displacement offset is used as input, and the control signal for the wheel leg lifting is output;

[0051] Step 2.4) Wheel Leg Lift Control: The vertical displacement offset is converted into motor speed using the formula N = (Δd / Δt) × (60 / p). This is used to calculate the speed of the lift servo motor 1. The output signal of the controller 19 is converted into a control signal for the lift system to drive the lift screw 3.

[0052] Step 2.5) Determine whether the height is adjusted correctly: Compare the difference △x between the actual height adjustment and the target height adjustment to see if the height adjustment is correct. If not, use the absolute value encoder to calculate the vertical displacement offset again and repeat step 2.3). If the steering is correct, the wheel leg lifting control ends.

[0053] like Figure 6 As shown, the control method also includes a process for monitoring wheel and leg slippage:

[0054] Step 3.1) Obtaining the walking speed v1: Acceleration data of the chassis vehicle during its movement is obtained through the gyroscope 14. The raw acceleration data obtained by the gyroscope 14 is filtered and calibrated to obtain more accurate and stable data. The processed acceleration data is integrated to obtain the speed data of the chassis vehicle during its movement.

[0055] Step 3.2) Obtaining the output speed v2: Obtaining the actual linear speed information of the wheel 16 by reading the output speed of the drive motor 9;

[0056] Step 3.3) Calculation of speed difference Δv: Compare the walking speed data obtained by the gyroscope 14 with the output speed of the drive motor 9 and calculate the speed difference Δv between the two;

[0057] Step 3.4) Slip determination: Based on the speed difference Δv, determine whether the wheel 16 is in a slipping state. If the speed difference exceeds a set threshold, it is determined that the wheel is slipping. If the speed difference does not exceed the set threshold, it is determined that the wheel is not slipping.

[0058] Step 3.5) Post-feedback measures: Based on the slip detection results, take shutdown protection measures or adjust the vehicle control strategy according to the priority settings, such as adjusting motor output, reducing acceleration, etc., to improve the slip problem.

[0059] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A highly integrated intelligent wheel leg with independent direction-changing and lifting functions, characterized in that: The wheel leg includes a lifting system, a walking system and a wheel leg control system. The lifting system performs lifting and adjusting of the wheel leg under the control of the wheel leg control system. The walking system is arranged at the lower end of the lifting system. The walking system performs free steering and normal driving under the control of the wheel leg control system. The wheel leg control system monitors the multi-axis posture, angle, length and linear speed of the wheel leg to determine the current working condition of the wheel leg and perform corresponding emergency control. The lifting system comprises a lifting servo motor (1), a lifting sleeve (4), a support sleeve (5), a lifting screw (3), a rotary bracket (7) and a lifting mounting plate (18), wherein the lifting mounting plate (18) is fixedly connected to the corresponding vehicle frame, the body of the lifting servo motor (1) and the lifting sleeve (4) are fixedly connected to the lifting mounting plate (18), the output shaft of the lifting servo motor (1) is connected through a coupling (2) and drives the lifting screw (3) to rotate, the lifting screw (3) is rotatably provided with a corresponding screw nut seat and the screw nut seat is fixed in the support sleeve (5), the outer side of the support sleeve (5) is slidably connected in the lifting sleeve (4) through a linear guide rail (6), so that the lifting servo motor (1) drives the support sleeve (5) to slide and lift in the lifting sleeve (4) through the lifting screw (3) and the corresponding screw nut seat, and the rotary bracket (7) is fixedly connected to the support sleeve (5) above it; The walking system comprises a rotary motor (8), a drive motor (9), a driving sprocket (10), a chain (11), a drive shaft (12), a driven sprocket (13), a gyroscope (14), a wheel (16), a housing sheet metal (15) and a motor mounting plate (17), wherein the body of the rotary motor (8) is fixedly connected to the rotary bracket (7), the gyroscope (14) is horizontally arranged on the housing sheet metal (15), the motor mounting plate (17) is fixed to the upper part of the housing sheet metal (15), and the drive shaft (12) is located below the motor mounting plate (17) and is rotatably connected to the lower part of the housing sheet metal (15). The output shaft of the rotary motor (8) is connected through a rotary turntable and drives the housing sheet metal (15) and the motor mounting plate (17) to rotate 360 degrees as a whole. The body of the drive motor (9) is fixed to the motor mounting plate (17). The output shaft of the drive motor (9) is connected through a corresponding reducer and drives the driving sprocket (10). The driving sprocket (10) is connected through a chain (11) and drives the driven sprocket (13) to rotate. The wheel axle of the driven sprocket (13) is connected to the drive shaft (12) of the wheel (16), so that the drive motor (9) drives the wheel (16) to rotate through a chain transmission.

2. The highly integrated intelligent wheel leg with independent direction-changing and lifting functions according to claim 1 is characterized in that: The wheel leg control system includes a gyroscope (14), an absolute value encoder, a controller (19), a motor drive, and corresponding lifting servo motors (1), rotary motors (8) and drive motors (9). The absolute value encoder is arranged at the lifting screw (3) to calculate the vertical displacement of the lifting screw (3) for estimating the lifting height of the wheel leg and transmit the estimated data to the controller (19). The gyroscope (14) is used to measure the lateral displacement angle θ1, walking speed v1 and acceleration data of the wheel leg and transmit the measured data to the controller (19). The controller (19) is connected to the corresponding host computer through a wireless module and judges the current working condition of the wheel leg according to the data transmitted by the absolute value encoder and the gyroscope (14), generates a corresponding drive signal and drives the operation of the lifting servo motor (1), rotary motor (8) and drive motor (9) through the motor drive control to achieve steering, lifting and leveling, adjustment of driving and emergency stop protection.

3. A control method for a highly integrated intelligent wheel leg with independent direction-changing and lifting functions according to any one of claims 1-2, characterized in that: The control method includes the wheel leg steering control process: Step 1.1) Acquisition of actual wheel leg deflection angle: Use the gyroscope (14) as a sensor to measure the lateral displacement angle θ1 of the wheel leg, which is used to provide wheel leg direction information; Step 1.2) Target direction angle acquisition: Output the wheel-leg target direction angle θ2 through the corresponding host computer; Step 1.3) PID algorithm outputs control signal: Based on the lateral angle θ1 and the target direction angle θ2, the output value of the controller (19) is calculated. The input of the controller (19) is the deviation of the lateral angle θ1, and the output is the control signal for controlling the steering; Step 1.4) Wheel leg steering control: convert the output signal of the controller (19) into the steering action of the wheel leg, and realize the steering by controlling the rotary motor (8); Step 1.5) Determine whether the steering is in place: by comparing the difference value △θ between the actual steering angle and the target direction angle θ2, check whether the steering is in place. If not, measure the lateral angle θ1 again through the gyroscope (14) and repeat step 1.3). If the steering is in place, the steering control is terminated.

4. The control method according to claim 3, characterized in that: The control method also includes a wheeled leg lifting control process: Step 2.1) Obtaining the actual vertical displacement offset: Use the absolute encoder to calculate the vertical displacement of the lifting screw (3) to estimate the lifting height of the wheel leg; Step 2.2) Obtaining the target vertical displacement offset: Output the target vertical displacement offset of the wheel leg through the corresponding host computer; Step 2.3) PID algorithm outputs control signal: Based on PID control, the difference value △x between the actual vertical displacement offset calculated by the absolute encoder and the target vertical displacement offset is used as input, and the control signal for the wheel leg lifting is output; Step 2.4) Wheel leg lifting control: The vertical displacement offset is converted into the motor speed using the formula N = (Δd / Δt) × (60 / p) to calculate the speed of the lifting servo motor (1). The output signal of the controller (19) is converted into the control signal of the lifting system to drive the lifting screw (3) to move; Step 2.5) Determine whether the height is adjusted correctly: Compare the difference △x between the actual height adjustment and the target height adjustment to see if the height adjustment is correct. If not, use the absolute value encoder to calculate the vertical displacement offset again and repeat step 2.3). If the steering is correct, the wheel leg lifting control ends.

5. The control method according to claim 3, characterized in that: The control method also includes a process for monitoring wheel and leg slippage: Step 3.1) Obtaining the walking speed v1: Obtaining the acceleration data of the chassis vehicle during its movement through the gyroscope (14), filtering and calibrating the raw acceleration data obtained by the gyroscope (14) to obtain more accurate and stable data, integrating the processed acceleration data to obtain the speed data of the chassis vehicle during its movement; Step 3.2) Obtaining the output speed v2: Obtaining the actual linear speed information of the wheel (16) by reading the output speed of the drive motor (9); Step 3.3) Calculation of speed difference △v: Compare the walking speed data obtained by the gyroscope (14) with the output speed of the drive motor (9) and calculate the speed difference △v between the two; Step 3.4) Slip judgment: According to the size of the speed difference △v, it is judged whether the wheel (16) is in a slipping state. If the speed difference exceeds the set threshold, it is judged that the wheel is slipping. If the speed difference does not exceed the set threshold, it is judged that the wheel is not slipping. Step 3.5) Post-feedback measures: Based on the slip detection results, take shutdown protection measures or adjust the vehicle control strategy according to the priority settings to improve the slip problem.

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