Optical-fiber/microprocessor-based remote velocity sensor

A remote velocity sensor has been developed that uses both a fiber optic system to monitor the position of an object and a microprocessor to track the object's position and calculate its average forward velocity between fiducial points (marks on a code plate). Sensing does not require electrical power at the sensing site, and the data are transmitted to the processing site by optical fibers whose inherent advantages include essential immunity to electromagnetic interference (EMI) and radio frequency interference (RFI). A feasibility model was designed, built, and evaluated that has a position resolution of 0.4 mm and is capable of calculating velocities up to 2.1 m/s with the particular code plate used.