Analysis of haptic interaction between Limbs in operations of vehicular driving interfaces

The advanced driver support system, including a by-wire system, has been studied to further improve safety and performance in driving an automobile. However, such systems have a possibility to cause the discomfort in the operation of driving interfaces because of unexpected supports to limbs' motion, the timing of support gap for a human driver, and so on. For such situations, a human-centric design based on human factors would be one of effective methodologies in developing an intelligent driving interface. Although a human driver usually manipulates his/her limbs simultaneously according to driving situations, evidences of haptic differences and interaction between the limbs in the operation of driving interfaces are still lacking to further improve driving comfort and safety. This study analyzes such human haptic factors in driving operations by the limbs with the originally developed laboratory driving simulator using mechatronic devices. Experimental results using ten healthy subjects (male university students) demonstrate the following two major points: 1) the perceived force magnitudes in steering by the limbs (limb) were equivalent to approximately 80 % (50 %) of the perceived force magnitudes in pedaling by the foot; and 2) the force perception properties for two pedals with different operational properties influenced each other in change-pedal operations.