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The measurement of piston temperature in a reciprocating engine has historically been a very time-consuming and expensive process. Several conditions exist in an engine that measurement equipment must be protected against. Acceleration forces near 2000 G's occur at TDC in automotive engines at rated speed. Operating temperatures inside the crankcase can range to near 150°C. To allow complete mapping of piston temperature, several measuring locations are required in the piston and data must be obtained at various engine operating conditions. Southwest Research Institute (SwRI) has developed a telemetry-based system that withstands the harsh environments mentioned above. The device is attached to the underside of a piston and temperature data is transmitted to a receiving antenna in the engine crankcase. The key element of this device is a tiny power generator which utilizes the reciprocating motion of the piston to generate electricity thus allowing the transmitter to be self-powered.

Motorcycle brake testing for accident reconstruction, compliance, or research, requires the measurement of several parameters to document system performance. To fully document brake system performance requires a data acquisition system with sensors for measuring speed, braking distance, temperatures, line pressures and actuation forces. Until recently, data acquisition systems have been, in general, too heavy, bulky, or limited in function for use on motorcycles. This study describes the design features, hardware, and performance of an on-board data acquisition system developed for motorcycle brake testing. The self-contained package has analog, digital, and counter channels which can be scanned at high frequency. The fully programmable unit can be optimized for varied applications. Speed and distance measuring accuracy are verified and compared to commonly used measurement methods such as speed traps, radar guns, and chalkmarkers.