Haptic actuator including field member multi-dimensional position determined based upon coil back electromotive force and motor constant values and related methods
AssigneeApple Inc.
InventorsArman HAJATI, Kayo YANAGISAWA
Life of this patent
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Abstract
A haptic actuator may include a housing, coils carried within the housing, and a field member moveable within the housing between the coils and including at least one permanent magnet. A controller may be coupled to the coils and configured to sense a respective back electromotive force (EMF) value of each of the coils and determine a position of the field member in dimensions based upon the back EMF values and motor constant values.
Claims27
A haptic actuator comprising:
- a housing;
- a plurality of coils carried within the housing;
- a field member moveable within the housing between the plurality of coils and comprising at least one permanent magnet;
- and
- a controller coupled to the plurality of coils and configured to
- sense a respective back electromotive force (EMF) value of each of the plurality of coils, and
- determine a position of the field member in a plurality of dimensions based upon the back EMF values and motor constant values.
A haptic actuator comprising:
- a housing;
- at least four coils carried within the housing;
- a field member moveable within the housing between the at least four coils and comprising at least one permanent magnet;
- and
- a controller coupled to the at least four coils and configured to
- sense a respective back electromotive force (EMF) value of each of the at least four coils,
- determine a position of the field member in a plurality of dimensions based upon the back EMF values and motor constant values, and
- drive each of the at least four coils based upon the position of the field member in the plurality of dimensions.
A method of using a haptic actuator comprising a housing, a plurality of coils carried within the housing, and a field member moveable within the housing between the plurality of coils and comprising at least one permanent magnet, the method comprising:
- using a controller coupled to the plurality of coils to
- sense a respective back electromotive force (EMF) value of each of the plurality of coils, and
- determine a position of the field member in a plurality of dimensions based upon the back EMF values and motor constant values.
Dependencies are inferred from the claim text.