Delft Haptics Lab

Development of a Haptic Interface for Evasive Maneuvers

Abstract

This MSc project was performed by Mauro della Penna. He graduated cumin laude on this thesis, which was nominated for best automotive thesis (Spyker Award). A subsequent patent was written based on this research.

Abstract – Current trend in automotive industries is to develop Intelligence Driver Support Systems (IDSS) that enable drivers to cope with the driving task more easily, safely and efficiently. A promising way to support drivers is to provide active feedback via the car’s controls. Recently intelligent haptic interfaces for the steering wheel and the gas pedal are investigated thoroughly. Their strength is to intuitively communicate to the driver the control actions required to maintain a safe field of travel. By scaling the intensity of the active feedback it is possible to shift the level of automation of the system from a support to an automatic controller. When designing IDSS, this capability has to be carefully used in order not to prohibit safe steering actions. If this is not achieved the drivers’ acceptability of such a system would be very limited with a consequent reduction of the safety benefits.

This thesis concerns the conceptual development of a haptic interface that is capable of supporting two reference trajectories. The proposed IDSS is designed for a particular highway condition in which the ego vehicle, driving with a stationary car-following behavior in the center lane of a three lanes highway, has to maneuver around the car ahead that drastically decreased its velocity. In this case the IDSS has to support both steering actions (left or right steering) without forcing an a priori solution. A novel concept is used to approach the problem: negative stiffness feedback. By reducing the steering stiffness the driver is free to choose the preferred action.

The system prototype was evaluated in a fixed-base driving simulator, in which 10 subjects performed an abstracted obstacle avoidance task, by steering to the left or the right. The main results are a reduction of about 60% of crashes and a significant reduction of control activity for high criticality. A decrease in response time of at least 100 ms is found independently from the criticality.