Joystick Steering Feedback Control for Four-Wheel Independent Steering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing four-wheel independent steering systems controlled by a joystick face challenges in maintaining control stability and efficiency due to lateral forces and yaw rates generated during turning, leading to unintended joystick manipulation and reduced steering angle control precision.
Innovation Solution
A control system that includes sensors to detect the shift position of a joystick and the driving speed of a vehicle, and a position controller to adjust the joystick position based on this data, maintaining a preset target steering angle through a left-right switching control motor. This system utilizes a PD controller, PI controllers, and a disturbance observer to enhance control stability and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a joystick is used to control a four-wheel independent steering system, then space utilization is improved and steering control is simplified, but lateral forces and yaw rates during turning cause unintended joystick manipulation and reduce control stability
Solution Approach 1:
The patent employs a feedback mechanism where sensors detect the actual steering angles of the four wheels and feed this information back to the controller. The controller compares the detected steering angles with the target steering angles calculated from joystick input and vehicle state, then adjusts the motor commands to correct any deviations. This closed-loop feedback system compensates for unintended joystick movements caused by lateral forces and yaw rates, maintaining control stability while preserving the simplicity of joystick operation.
Solution Approach 2:
The patent introduces an intermediate control system that acts as a mediator between the joystick input and the actual wheel steering. The controller calculates target steering angles based on joystick position and vehicle state (speed, direction), then uses motor actuators to precisely control the steering mechanism. This intermediary layer filters out unintended joystick movements and translates operator intent into accurate wheel steering, resolving the contradiction between simple joystick operation and stable control.
2Ease of operation
If a joystick with limited manipulation radius is used, then space utilization is improved, but the ability to control steering angle with small input is reduced
Solution Approach 1:
The patent transitions from direct one-to-one joystick control to a multi-dimensional control approach. The controller considers not only joystick position but also vehicle speed, driving direction, and actual wheel steering angles to calculate target steering angles. This multi-dimensional control strategy amplifies the effect of small joystick movements, allowing precise steering angle control even with a joystick having limited manipulation radius, thus maintaining both space utilization and control precision.
Solution Approach 2:
The patent dynamically adjusts control parameters based on vehicle state. The controller modifies the relationship between joystick input and steering output according to vehicle speed and driving conditions. At different speeds and operational states, the system applies different gain factors and control algorithms, enabling precise steering control with small joystick movements while maintaining the compact joystick design for space efficiency.
3Reliability
If secondary control mechanisms are added to compensate for unintended joystick manipulation, then control stability is improved, but device complexity increases
Solution Approach 1:
The patent designs a universal controller that performs multiple functions: it processes joystick input, calculates target steering angles, monitors actual wheel positions via sensors, and adjusts motor commands to correct deviations. This single multi-functional control unit integrates what would otherwise require separate secondary control mechanisms, achieving control stability without proportionally increasing system complexity. The controller acts as a smart intermediary that handles both primary steering control and compensation for unintended movements.
Data Source
AI summary
A control system for a four-wheel independent steering system includes at least one sensor configured to detect at least one of a shift position of a joystick, mounted on the four-wheel independent steering system, or a driving speed of a vehicle, and a position controller configured to control a position of the joystick based on sensing data detected by the at least one sensor.