Hiroshi Okiyama

Biomechanical and Psychophysical Evaluation of Operating Loads in Vehicular Driving

The present paper proposes an evaluation method of operation loads in vehicular driving, such as the joint-load, the seat pressure, and the perceiving force, based on biomechanical and psychophysical evidences to assist the human-centered design of driving interfaces. The prototype simulator is developed by means of a big experimental data of human motor properties and force-perception properties related with driving operations. The usefulness of the proposed methodology is then demonstrated through a set of simulation experiments in the case of the curve traveling situation.

A study on design factors of gas pedal operation

Lateral distance from the center of a drivers seating position to the gas and brake pedals is one of the main design factors that relates to the ease of stepping on the pedals from one and the other. It is important to keep a certain distance between the pedals to prevent erroneous operations or to reduce the drivers anxiety. In this paper, we explain that the distance between the pedals is affected by the drivers seating height. In other words, if the driver sits lower, the accuracy of stepping on the pedals from the gas pedal to the brake pedal will increase compared to the higher seating position. In addition, we found out that providing auxiliary parts for the leg support enhances the accuracy of the pedal operations. Language: en

Seat Lumbar Support Evaluation With ASPECT Manikin

Seat lumbar support is thought to be essential for seating comfort as it plays important role in the drivers fatigue during long term driving. We tried to evaluate the lumbar support performance objectively with Seat Pressure Distribution. First, the tolerance in the measurement was eliminated by application of ASPECT manikin that reproduced a human seating torso posture [1, 2]. Second, an analysis method to visualize the seat support balance on the human back was developed. Third, a hypothesis for the optimal support balance to minimize the fatigue was proposed according to the fatigue growing mechanisms. Examining the deviation of each seat result from the optimal support, the performances were quantitatively evaluated. In addition to that, the effect of the lumbar support adjuster was taken into consideration to predict the market evaluation more precisely.

Seat Lateral Support Evaluation With SAE Manikin

In this report, we proposed an objective evaluation method of the seat lateral support according to the mechanisms to create the performance differences that we reported previously [1]. First, we showed an effect of scrutinizing Seat Pressure Distributions change during vehicle turn to gain a quantitative index for explaining subjective evaluation results. Second, we showed the examples of the differences of the results according to the subjects and selected the best-correlated subject among them with a market survey result. Then, we contrived a loading condition to SAE manikin to reproduce the subjects Seat Pressure Distribution. Final, by a specific calculation of the Seat Pressure Distribution, the method to indicate the performance rating that had strong correlation with market survey was clarified.