LIGHTWEIGHT PERMANENT MAGNET ACTUATORS AND MANIPULATORS

PERMANENT MAGNETS BASED ON ND2FE14B AND PR2FE14B EXHIBIT VERY HIGH MAGNETIC ENERGY PRODUCTS AT ROOM TEMPERATURE. THESE COMPOSITIONS HAVE BEEN SLIGHTLY MODIFIED BY ADDING COBALT AND ALUMINUM TO EXTEND THEIR UTILITY OVER A WIDE TEMPERATURE RANGE. FOR EXAMPLE, A PR-FE-B MAGNET RECENTLY PRODUCED IN OUR LABORATORY EXHIBITED AN ENERGY PRODUCT OF 50 MGOE AT 77 K. WE HAVE ALSO DEVELOPED PR-FE-CO-A1-B MAGNETS WHICH ARE MORE EFFICIENT BY A FACTOR OF 1.5 AT HIGH TEMPERATURES (25-150 DEGREES CENTIGRADE) IN THEIR TEMPERATURE COMPENSATION BEHAVIOR COMPARED TO ND-FE-B MAGNETS. THE HIGH MAGNETIC ENERGY PRODUCT OF PR-FE-B MAGNETS WILL TRANSLATE INTO A HIGHER TORQUE-TO-WEIGHT RATIO IN MANY ELECTROMECHANICAL SYSTEMS. WE PROPOSE TO UNDERTAKE DESIGN STUDIES AND TO DEVELOP PROTOTYPES OF LIMITED DISPLACEMENT ACTUATORS AND RELUCTANCE POSITION SENSORS EQUIPPED WITH PR-FE-B PERMANENT MAGNETS. THESE DEVICES ARE EXPECTED TO FUNCTION SMOOTHLY AND RELIABLY OVER A WIDE TEMPERATURE RANGE IN TELEROBOTIC ELECTROMECHANICAL SYSTEMS. IN VIEW OF THEIR HIGH TORQUE-TO-WEIGHT RATIO, THEY ARE EXPECTED TO REDUCE THE PAYLOAD IN SPACE APPLICATIONS.