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A concept is presented for remote, autonomous sensors, which includes an on-board power supply, signal transmission, a sensing element, and a controller. Sensors can be deployed without direct connection for either signal transmission or energy supply. The power supply can be used to power many types of remote sensors, and includes microscopic batteries, an energy converter, and a simple charger. The batteries combine high power density (W/cm2) and sufficient capacity to power sensors for extended periods of time without recharge.

This paper describes electrochemical behavior of microscopic batteries based on both the lithium/ion and Ni/Zn couples. These batteries are being developed for use in MEMS devices and other microelectronics, especially remote, autonomous sensors. Many of these applications require a combination of long cycle life, moderate energy storage capability, and periodic high power output. Batteries have been made using high-volume, lowcost, fabrication techniques, described in prior publications. These batteries have been built and evaluated for their electrochemical performance. Power output from both types of cells is impressive; current densities of 80 - 100 and 20 - 50 mA/cm2 have been observed, for discharges of several seconds, for Ni/Zn and Li/Ion cells, respectively. Much higher current densities are observed for discharges lasting a few milliseconds, such as would be needed in many applications. Specific capacities of 2 - 4 C/cm2 are also obtained.

The United States Army Tank Automotive Research, Development and Engineering Center (TARDEC) built systems to measure the suspension parameters, center of gravity, and moments of inertia of wheeled vehicles. This is part of an ongoing effort to model and predict vehicle dynamic behavior. The new machines, the Suspension Parameter Identification and Evaluation Rig (SPIdER) and the Vehicle Inertia Parameter Evaluation Rig (VIPER), have sufficient capacity to cover most heavy, wheeled vehicles. The SPIdER operates by holding the vehicle sprung mass nominally fixed while hydraulic cylinders move an “axle frame” in bounce or roll under each axle being tested. Up to two axles may be tested at once. Vertical forces at the tires, displacements of the wheel centers in three dimensions, and steer and camber angles are measured.