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Electric vehicle range must be extended to make electric vehicle use attractive. Other than propulsion, climate conditioning is the heaviest user of energy. An efficient, novel climate control system coupled with an energy management system is described and its energy usage is estimated and compared to that of a conventional system. The example presented here is for a shuttle bus used for carrying approximately fifteen passengers on short, frequently repeated routes, but the concepts are equally applicable to personal electric vehicles.

Although the performance of most of today's airbag crash sensor systems is excellent, it is achieved by using multiple sensors located remotely from the passenger compartment. Those systems which use single sensors in the passenger compartment sometimes fail to actuate when needed or are too slow to provide optimum occupant protection. Installed airbag system cost now suggests that designers should find ways to reduce the number of sensors and the complexity of the system without suffering degradation in performance. An electronic sensor is freed from the constraints of the differential equation of motion of an electromechanical sensor because its algorithm can, in principle, be arbitrary. It can manipulate the acceleration data in new ways, but whatever algorithm is employed must be firmly grounded in some understood physical process to guarantee the ability of the algorithm to perform properly in real world events not recreated on the test track.

A new spring mass crash sensor has been designed which employs a novel method of gas damping. The damping is accomplished in a way which is quite forgiving to manufacturing tolerances thus reducing the overall cost of the device. Rather than using the gas damping to achieve a constant velocity threshold level, the threshold is made quite large for short duration impulses such as those arising from maintenance shocks, thrown rocks and undercarriage strikes. Thus, the need for a safing sensor is eliminated. Evaluation of this sensor is now taking place at a number of automobile manufacturers. A possibility exists that because of the extreme design flexibility afforded by this sensor, a single sensor system can be made. The sensor now has electrical output but straightforward modifications are now being made to design a version with mechanical output for use in purely pyrotechnic systems.