Design of pedal characteristics making use of human leg mechanical properties

Abstract

Vehicle pedal operations are classified as acceleration, transfer between the brake pedal and the accelerator, clutch operation, and braking. This paper deals with the first three without feeling factors. In terms of leg motion, these operations are classified as ankle movement, leg movement and pedal-change movement. In the study reported here, pedal characteristics were analyzed experimentally to clarify the mechanical properties of the leg and related effects on muscle activity. Ankle joint movement is involved in fine adjustment of the accelerator, leg movement is involved in the large motion of depressing the clutch, and ankle joint movement is involved in switching between the brake and the accelerator. The results highlighted three points in particular: (1) Ankle joint movement depends on the force used to depress the accelerator, and involves comprehensive consideration of joint movement, leg muscle activity and seat pressure distribution. (2) Leg movement for the application of foot force to operate the clutch is the greatest in the region of the maximum point near the pedal force. These are easy to operate and a lower burden is placed on the leg. (3) Pedal-change movement can be implemented more precisely when the accelerator-brake pedal transfer path is low and the lateral position of the accelerator is an appropriate distance from the operator’s body center. Comprehensive consideration of these results is expected to be useful in the design of vehicle pedals.

Keywords

• human machine matching
• pedal operation
• accelerator
• brake
• cluch