An electrical caliper for continuous measurement of relative displacement

An electrical recording caliper for the continuous measurement of relative displacement has been developed. The details of design, operation, and performance are described. The frequency response was uniform (±5%) through 25 cycle/sec. An approximately 0.5% error related to the mechanical impedance of the device was estimated to occur. The system is linear and free of hysteresis. Base-line and gain stability are acceptable. Submitted on July 21, 1961