Marine System Steers Electric Car

Robert N. Boggs, Southern Technical Editor

Palm Bay, FL-Basically, there are two ways to view an electric car. One perceives a vehicle with the performance and range of a gasoline-powered family car. but powered electrically. It' s quite clear that the development of such a vehicle will have to wait for some dramatic breakthroughs in battery technology.

The other recognizes that the vast majority of auto trips are short: to work. to school. to the store. Many such trips include just one or two people. A range of 300 to 400 miles and 0 to 60 times of under 9 seconds are overkill for these trips.

With short trips in mind, engineers at Renaissance Cars, Inc., started with the proverbial clean sheet to design the Tropica. Car and Driver describes the result as "a great-looking, fair-weather. short-range, urban roadster-a fun second car." The engineers approached each component and system with an open mind, looking for effective, lightweight, not necessarily traditional design.

Steering wheel connects directly to the hydraulic steering pump. The short assembly does not pose the safety problems of a long steering shaft.

In the steering system, for example, they wanted to avoid the weight and safety problems of the standard steering-column/rack-and-pinion setup. "From the boating g industry, we adapted the system that steers many small boats," says James Muir, Renaissance's VP of design.

The steering wheel directly drives a small hydraulic pump, measuring 4.25 inches in diameter by 4 inches long. Quarter-inch ID hoses carry fluid between the pump and the steering cylinder.

Two turns lock-to-lock give a curb-to-curb turning circle of 30 ft with a total cylinder stroke of just 5 inches.

The vehicle's chassis is aluminum. Batteries with enough energy-storage capacity to satisfy the 65-mile range requirement are carried in a slide out tray. Engineers located the tray and its load of batteries low on the Tropica's centerline.

Additional details...Contact James H. Muir, Renaissance Cars, Inc., 2730 Kirby Rd., Palm Bay, FL 32905, (407) 676-2228.