Apple Inc.

Western Digital (Fremont), Inc.

Hong Pan

John Greer Elias

Xiao Z Wu

Savas Gider

Jian Guo

Muhammad F Hossain

Nicholas C Soldner

Kathy X Tang

Anthony Y Fai

Seth E Woiszwillo

Systems, methods, apparatuses and non-transitory, computer-readable mediums are disclosed for short-range position tracking using a stationary magnetic field gradient. In an embodiment, a method comprises: obtaining, by a sensing array of a device worn or held by a user in an environment, a measurement of a stationary magnetic field generated by a magnetic source in the environment, the stationary magnetic field being independent of an ambient magnetic field in the environment; determining based on the measurement, a change in the magnetic field over time; determining based on the measurement, a change in the magnetic field over distance; obtaining, by the processor, a rotation angle of the device; determining a velocity of the device based on the change in the magnetic field over time, the change in the magnetic field over distance and the rotation angle of the device; and integrating the velocity to obtain a position of the device.

Short-range position tracking using stationary magnetic field gradient

A head-mountable device can securely support sensors in a manner that maintains their positions and orientations over time and avoids applying excessive strain on the sensors, thereby protecting them from harm. The sensor can be mounted on a flex circuit or circuit board, which is rigidly secured within an inner case, including for example a base and an inner shield. The inner case can be suspended within an outer case, including for example a frame and an outer shield. Shock absorbers on opposing sides of the inner case can flexibly couple the inner case to the outer case. The shock absorbers can dampen the effects of vibrations or other forces applied from the outer case. The inner case can decouple the sensor from strain applied from the shock absorbers.

Sensor assembly for head-mountable device

A data storage device is disclosed wherein when a first head is over a top disk surface, a first undershoot of a first cross-track profile is closer to an inner diameter of a disk and a second undershoot of the first cross-track profile is closer to an outer diameter of the disk. When a second head is over a bottom disk surface, a second undershoot of a second cross-track profile is closer to the inner diameter of the disk and a first undershoot of the second cross-track profile is closer to the outer diameter of the disk.

Data storage device employing mirrored cross-track profiles for top and bottom disk surfaces

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Fremont, CA, United States of America

Hong Pan