Research on effects of pattern, amplitude and frequency of pulse steering torque warnings for lane departure

• Square pulse steering torque is more effective than triangular pulse one.
• Large amplitude pulse torque can improve the execution of correction maneuvers.
• Frequency of 10 Hz realizes promise between effectiveness and drivers’ acceptance.

Driver’s inattention is the main reason for lane departure accidents in highway traffic. In this paper, the pulse steering torque warnings technique is studied, and the effects of pattern, amplitude and frequency of pulse steering torque warnings on the effectiveness and customers’ acceptance are studied through in-door experiments based on a fixed-based driving simulator. Prototypes of lane departure warning system with twelve parameter settings were developed. Three-ways repeated measures ANOVAS and t-test are used to assess the effects of warning systems. The steering behaviors of 20 drivers during lane departure are analyzed. The experimental results show that both primary and secondary interaction of amplitude, frequency and pattern are not significant. The superimposed square pulse steering torque is more effective than triangular pulse one. There is little difference of drivers’ preference in pulse patterns. Although large amplitude is less accepted by drivers, it improves the correction maneuver greatly. 10 Hz is a preferred frequency, which achieves a compromise between effectiveness and drivers’ acceptance. Thus, the combination of small amplitude, square and mid-frequency is the best compromise for practical application.