Intuitive Human-Machine Steering Interface for 4WIS and Synchronous Steering Interaction Control Considering Steering Intention

Recent advancements in electric chassis technologies such as steer-by-wire (SBW), in-wheel motors, and e-corner modules have highlighted the potential of four-wheel independent steering (4WIS) vehicles. Although these vehicles offer expanded motion capabilities, conventional interfaces with one steering DOF are insufficient to implement expanded motions. To address this, this paper proposes an intuitive human-machine steering interface (HMSI) capable of effectively capturing driver steering intention with synchronous steering interaction control. The proposed HMSI supplements the conventional steering wheel with additional DOFs, enabling intuitive and continuous control of various vehicle motions. The developed control method distinguishes intentional steering inputs from unintended disturbances, providing clean steering commands suitable for safe vehicle control. Driver torque inputs are estimated using a sensorless disturbance observer-based approach, while an admittance control-based interaction model dynamically provides steering force feedback. Experiments validate that unintended motions are effectively damped, and intentional steering inputs are extracted, ensuring stable vehicle handling. Additionally, the proposed system demonstrates the capability to vary steering feel, paving the way for future research on adaptive steering feel generation and motion-command methodologies in 4WIS vehicles.