Strain Rate Sensor for Vibration Control in Large Flexible Structures

Period of Performance: 09/27/1990 - 09/27/1992


Phase 2 SBIR

Recipient Firm

IAP Research, Inc.
2763 Culver Avenue Array
Dayton, OH 45429
Principal Investigator


Low inherent damping in space structures presents serious problems. The most practical approach to increase the effective damping in these structures is augmenting them with active control systems. IAP's Phase I study analytically and experimentally established the feasibility of a new sensor that directly measures structural strain rates during vibration, active control of space structures. The transducer is based on electromagnetic technology and is called the Variable Reluctance Transformer Strain Rate Sensor. The physics of the sensor is simple: a time-varying change in magnetic circuit reluctance produces a voltage across output windings. In Phase I, IAP established the feasibility of this concept with analysis and experiments. In Phase II, IAP's research effort will target VRT Strain Rate Sensor performance to meet the needs of the space structures mission. The sensor will have desirable sensitivity, output voltage, signal-to-noise ratio, bandwidth, and mass. This solution for the space structure control problem will also make significant contributions in commercial applications such as robot manipulators, seismic control of buildings, and even possibly in the active automobile suspensions of the future.