Abstract: A target device is carried by or mounted on a first part movable relative to a second part. The second part has a sensing device including an array of sensors providing outputs responsive to the magnet field of the target device. A processing device receives the outputs of the sensors and calculates relative positions of the two parts based on the outputs.

Abstract: A target device is carried by or mounted on a first part movable relative to a second part. The second part has a sensing device including an array of sensors providing outputs responsive to the magnet field of the target device. A processing device receives the outputs of the sensors and calculates relative positions of the two parts based on the outputs.

Abstract: Disclosed is a method of designing a position sensor having a plurality of coils so that the total impedance of the sensor varies according to a desired impedance function. The method includes the steps of modelling the position sensor on a computer using a finite element analysis program to determine the vector potential and current density within the sensor due to a known current flowing in each of the coils. A set of matrix equations is then developed that relates vector potential, the current density and the number of turns, N.sub.i, in each coil to a point on the desired impedance function. The set of matrix equations is then optimized to determine the number of turns, N.sub.i, that each coil should contain, so that the total impedance of the sensor varies according to the desired impedance function.