Shaped Strain Sensors for Intelligent Structures.
Final rept. 1 Nov 91-31 Jan 94,
MASSACHUSETTS INST OF TECH CAMBRIDGE
Pagination or Media Count:
Tbe design of sensors for use in the control of intelligent structures is investigated. It is found that certain spatially averaging strain sensors can be used to satisfy these requirements. The output and transfer function characteristics of spatially averaging sensors with arbitrary weightings are derived for both sinusoidal and exponential strain fields. An interpretation of shaped sensor behavior is given which explains how the rolloff of shaped sensors can occur for a simulated pinned-pined beam with collocated Barrett and point sensors. Experiments using clamped-free beams fitted with different spatially averaging strain sensors are conducted to verify the predicted rolloff rate of the sensor transfer function. Result of the tests indicates that the sensors rolloff can be predicted if the sensors in the experiment can be implemented properly. In order to investigate the possibility of using an array of spatially averaging sensors to estimate global structural shape, the dynamic mode shapes of pinned-pinned and clamped-free beams are also estimated using a variety of sensor weightings and integration rules. Intelligent structures, Shaped strain sensors.