A variable reluctance sensor

The author presents the characteristics and the performance of a novel variable-reluctance sensor. He describes two designs for this inductive transducer which are very easy to realize. They are based on two shapes, both of which generate a sinusoidal variation of the air gap and therefore an inversely sinusoidal variation of the reluctance. The first shape utilizes an off-centering rotor, the second a buckled surface. The performance, resolution (15 bits), and accuracy (+or-3 of arc) of the prototype are presented. The prototype demonstrates the good measurement performance of this low-cost shaft-angle transducer, as well as its robustness, reliability, and stability.<
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