Shared control between human and machine: haptic display of automation during manual control of vehicle heading

In this paper, a paradigm for shared control is described in which a machine's manual control interface is motorized to allow a human and an automatic controller to simultaneously exert control. The manual interface becomes a haptic display, relaying information to the human about the intentions of the automatic controller while retaining its role as a manual control interface. The human may express his control intentions in a way that either overrides the automation or conforms to it. The automatic controller, by design, aims to create images in the mind of the human of fixtures in the shared workspace that can be incorporated into efficient task completion strategies. The fixtures are animated under the guidance of an algorithm designed to automate part of the human/machine task. Results are presented from 2 experiments in which 11 subjects completed a path following task using a motorized steering wheel on a fixed-base driving simulator. These results indicate that the haptic assist through the steering wheel improves lane keeping by at least 30% reduces visual demand by 29% (p<0.000!) and improves reaction time by 18 ms (p=0.0009).