Abstract: A GMI sensor for determining spin rate of a rotating body within an external magnetic field is presented. The sensor comprises an oscillator generating an AC drive signal at an oscillator output terminal. A voltage divider circuit includes a first terminal AC coupled to the oscillator output terminal through a coupling capacitor, and a second terminal electrically connected to a reference ground. The voltage divider circuit further includes a GMI fiber having a GMI junction terminal. The fiber is disposed in fixed relation to the rotating body such that impedance of the fiber is modulated by the external magnetic field to provide a modulated drive signal at the GMI junction terminal. A signal processing circuit is electrically connected to the GMI junction terminal to processes the modulated drive signal and provide an output signal indicative of the spin rate of the rotating body.

Abstract: A method and apparatus for determining the orientation of an object relative to a reference magnetic field includes establishing generally adjacent to the object a modifiable magnetic field. The direction of the modifiable magnetic field is changed among a plurality of predetermined, known orientations relative to the object. A resultant magnetic field, including the reference magnetic field and the modifiable magnetic field, is repeatedly measured adjacent to the object. The step of measuring is directed outwardly from adjacent to the object in predetermined directions that are fixed relative to the object to determine when the magnitude of the resultant magnetic field is minimized or maximized indicating that the direction of the modifiable magnetic field is parallel with that of the reference magnetic field. Thereupon, the orientation of the object is correlated to the known orientation of the modifiable magnetic field.

Abstract: A rotational speed/tip sensor combines a tip sensor and a speed sensor in one compact package for use on a motorcycle. The tip sensor includes a disk and a sensing device that detects the absence or presence of the disk in the apex of a V-groove. If the motorcycle tips over, the disk rolls out of the V-groove apex and actuates the tip sensing device to open a circuit through a speed sensing device and thereby shut down the motorcycle engine. The tip and speed sensors are assembled to a housing that is mounted to the engine. Only three wires are used to connect both the tip sensing device and the speed sensing device to the engine control.