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Current vehicle climate control systems are dramatically overpowered because they are designed to condition the cabin air mass in a specified period of time. A more effective and energy efficient objective is to directly achieve thermal comfort of the passengers. NREL is developing numerical and experimental tools to predict human thermal comfort in non-uniform transient thermal environments. These tools include a finite element model of human thermal physiology, a psychological model that predicts both local and global thermal comfort, and a high spatial resolution sweating thermal manikin for testing in actual vehicles.

The steering system is one of the most important human interfaces in a vehicle and it must be designed to ensure safety and comfort for the driver. However, these characteristics are difficult to express quantitatively. Therefore, the current controller design requires many experimental steps. One possibility to reduce the number of the steps is to use the concept of passivity. In this paper, we explore useful conditions from the viewpoint of passivity in the controller design for vehicle steering. Controllers involving damping, inertia compensation, and vibration suppression in electric power steering systems are proposed.

In this study, preview control algorithms for the active and semi-active suspension systems of a full tracked vehicle are designed based on a 3-D.O.F model and evaluated. The main issue of this study is to make the ride comfort characteristics of a fast moving tracked vehicle better to keep an operator's driving capability. Since road wheels almost trace the profiles of the road surface as long as the track doesn't depart from the ground, the preview information can be obtained by measuring only the absolute position or velocity of the first road wheel. Simulation results show that the performance of the sky-hook suspension system almost follows that of full state feedback suspension system and the on-off semi-active system carries out remarkable performance with the combination of 12 on-off semi-active suspension units.