Patent ID: 8289115
Filing Date: 2012-10-16
Classification: G05B,G06F,Y10T

Abstract:
1. A method of continuously monitoring by a tablet device pivotally attached to a cover, a pivot angle of the cover in relation to the tablet device, the cover comprising a magnet, the tablet device comprising a processor coupled to which is a display having a top protective layer, a magnetic sensor configured to detect a magnetic field from the magnet through the top protective layer, and an inertial system configured to determine a spatial orientation of the tablet with respect to an inertial reference frame, in a closed configuration the pivot angle is 0 radians and the magnetic sensor is substantially co-planar with the magnet and separated by a first distance R 0 and detects a first magnetic field value propagating through the top protective layer from the magnet, and in an open configuration, the pivot angle is it radians and the magnetic sensor is substantially coplanar with the sensor and separated by a second distance R 1 , and detects a second magnetic field value propagating from the magnet, the second distance R 1 being greater than first distance R 0 , the method comprising: sensing a current magnetic field value from the magnet by the magnetic sensor; determining a relative magnetic field value by comparing the current magnetic field value to the first and second magnetic field values; determining a current spatial orientation of the tablet device with respect to the inertial reference frame by the inertial system; adjusting the relative magnetic field value in accordance with the current spatial orientation; and providing a current pivot angle in accordance with the adjusted relative magnetic field value.