Modulation of Control Authority in Adaptive HapticShared Control Paradigms

TL;DR

This paper introduces an adaptive haptic shared control framework with a novel self-regulating impedance controller, enabling smooth control authority modulation between human and automation in steering tasks, demonstrated via simulation studies.

Contribution

It proposes a new impedance control method and an optimal modulation policy using nonlinear model predictive control for adaptive shared steering control.

Findings

Effective control authority modulation demonstrated in simulations

Improved cooperation between human and automation in obstacle avoidance

Flexible control transfer modes for different interaction scenarios

Abstract

This paper presents an adaptive haptic shared control framework wherein a driver and an automation system are physically connected through a motorized steering wheel. The automation system is modeled as an intelligent agent that is not only capable of making decisions but also monitoring the human's behavior and adjusting its behavior accordingly. To enable the automation system to smoothly exchange the control authority with the human partner, this paper introduces a novel self-regulating impedance controller for the automation system. To determine an optimal modulation policy, a cost function is defined. The terms of the cost function are assigned to minimize the performance error and reduce the disagreement between the human and automation system. To solve the optimal control problem, we employed a nonlinear model predictive approach and used the continuation generalized minimum residual method to solve the nonlinear cost function. To demonstrate the effectiveness of the proposed approach, simulation studies consider a scenario where the human and the automation system both detect an obstacle and negotiate on controlling the steering wheel so that the obstacle can be avoided safely. The simulations involve four interaction modes addressing the cooperation status (cooperative and uncooperative) and the desired direction of the control transfer (active safety and autopilot).