Control Interface for Next Generation Vehicles: What Is the Best Way to Drive Four-Wheel Independent Steering Vehicles?

Four-wheel independent steering (4WIS) vehicles refer to vehicles designed to be able to move in multi-orientation by eliminating the mechanical linkage among the wheels. This study aims to evaluate and compare the usability of previously proposed 4WIS vehicle controllers. A usability test with 33 drivers was conducted to compare the five control interfaces (steering wheel buttons, touchscreen buttons, center console buttons, joystick, and paddle shifters). In order to identify what factors contributes to the usability of 4WIS control interfaces, we utilized a mixed-method approach that collects and analyzes both quantitative and qualitative data within the study. The quantitative results indicate that button-type interfaces shorten task completion time and reduce workload than joystick or paddle shifters. Qualitative analysis implies that touchscreen buttons reduce the perceived safety of drivers due to the lack of tactile feedback. Design recommendations for 4WIS control interfaces were provided from the usability testing results.