The Effects of Haptic Feedback and Transition Type on Transfer of Control Between Drivers and Vehicle Automation

• Published in: IEEE transactions on human-machine systems 2021-12, Vol.51 (6), p.613-621
• Main Authors: Cutlip, Steven, Wan, Yuzhi, Sarter, Nadine, Gillespie, R. Brent
• Format: Article
• Language: English
• Subjects: Advanced driver assistance systems; Automatic control; Automation; Driving conditions; Factorial design; Feedback; Haptic interfaces; Haptics; Smoothness; Steering; Switching; Vehicle safety
• ISSN: 2168-2291; 2168-2305
• DOI: 10.1109/THMS.2021.3107255

When driving conditions exceed the design limits of an automation system, transfers of control back to a human driver become necessary. Such transfers may compromise safety, since a driver typically requires time to get back into the loop. Various schemes for combining human and automatic control over steering have been proposed to address the challenges of transferring control smoothly. This article presents the findings from a simulator study that compared four such schemes. The driver initiated a transfer of control either by pressing a button and assuming full control of the vehicle (switching transition) or by overpowering an automation that continued to act on the vehicle. Two additional factors in the \text{2} \times \text{2} \times \text{2} factorial design are the availability of haptic feedback and the inclusion of a secondary task. To examine the robustness of each scheme, all driving scenarios involved nominal and off-nominal conditions. The findings from this study demonstrate the benefits of haptic shared control (i.e., overpowering transitions with haptic feedback) for facilitating transfers of control between a human driver and vehicle automation. Haptic-feedback-enhanced drivers' awareness of automation input and the status of the vehicle while the overpowering transitions improved the smoothness of interventions, compared to switching transitions.