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A technique has been developed which can combine the Peukert, as well as the diffusion based “recovery”, characteristics of a battery pack with a given vehicle design and driving cycle to determine cost of operation. The technique utilizes a mathematical model of the vehicle to determine energy usage, and combines this with a mathematical model of the battery pack to determine apparent depth of discharge (DOD). This technique has been applied using the characteristics of a pasted plate, flooded, lead-acid battery pack and the Federal Urban Driving Schedule (FUDS). The results are compared to test data from the California Air Resources Board (CARB) and the Sacramento Municipal Utility District (SMUD). As lead acid batteries have a cycle life which is strongly related to DOD, it is possible to then relate battery life to the distance driven between charging.

The purpose of this paper is to present specifications for rubber tired vehicles operating on a cooperative highway. These specifications will allow control systems to be designed which could meet the requirement of a new generation of automobiles and trucks operating on roadways which can carry more vehicles/hr. These vehicles are to be electronically guided and controlled. The problem is divided into two aspects: 1. lateral control and 2. longitudinal control. Lateral control will be done by a sensor system that can “see” the road ahead and steer the vehicle toward the road and will be presented in another paper. Longitudinal control will be the subject of this paper. It involves keeping a series of dissimilar vehicles properly spaced while operating at high speeds. Safe spacing must be kept as vehicles enter and exit the vehicle stream, and as disturbances occur such as hills and winds.

Continuously Variable Transmission vehicles have been around since the turn of the century. The coordination between the engine and transmission has always been controversial. Many techniques have been proposed from a simple constant engine speed policy to a policy which attempts to make the engine operate at its best efficiency for any power output. These techniques are compared and developed by computer simulation with respect to performance and fuel economy. Implications on engine design are discussed.

The purpose of this paper is to describe the design and simulation of the urban vehicle power train system of the University of Wisconsin at Madison. The objective of the power train is high fuel efficiency as well as low emissions. Fuel efficiency is achieved by an on-off operation of the internal combustion engine with the “on” operation at only the minimum brake specific fuel consumption area. Emission control is partially achieved by utilizing an electric drive system for transient response. Furthermore, low emissions and fuel efficiency are bettered by techniques such as special starting without choke, no deceleration, and no idle requirements on the internal combustion engine.