Abstract: In accordance with this invention, a noncontacting sensing system (12) is disclosed for providing information regarding the gap between, and relative position of, two relatively movable elements such as a vehicle (14) and a guideway (16). As its main component, the system (12) includes an array (64) of four sensor assemblies (66). Each assembly (66) defines a target magnetic loop (T), which includes adjacent discrete pole pieces (28) in the guideway (16), and a separate reference magnetic loop (R). Hall-effect pickups (84) employed in the two loops (T and R) provide information regarding the relative magnetic intensity in the loops. A microprocessor (109) divides the output of the target loop pickups (88, 90, 92, and 94) by that of the reference loop pickup (96), in accordance with instructions provided in a read-only memory (ROM)(106). As a result, a corrected signal is produced for each assembly (66) independent of time-varying factors of the assembly (66).

Abstract: Disclosed is a single, integrated linear synchronous unipolar motor having high-energy permanent magnets operable along a substantially linear demagnetization curve and a polyphase coil. Collectively, the permanent magnets and polyphase coil provide for propulsion, suspension, braking and lateral control of a vehicle along a passive reaction rail. The permanent magnets provide the primary force for suspending the vehicle from the guideway, with a DC field control coil controlling the suspension gap between the vehicle and the reaction rail. The polyphase coil propels the vehicle along the track at a speed dependent upon the voltage and frequency of the supplied signal. The motor exhibits a high power factor and efficiency factor, resulting in a motor that can be operated from a power source having a lower KVA rating than that required for previous linear motor arrangements and that can be used in concert with a low-cost, passive guideway.