Abstract: Examples of the disclosure are directed to micro-machined ultrasonic transducers (MUTs) which can be embedded into a flexible band of a watch to detect touch, gestures, physiological signals, and transfer data. In some examples, the MUTs can include a piezoelectric material disposed between two electrodes and coupled to a base material having a plurality of cavities, to support motion of the transducer structure. In some examples, the MUTs can be coupled to multiplexing circuitry to stimulate, configure and control the MUTs. In some examples, the size, shape, and arrangement of transducers can be changed to improve characteristics associated with ultrasonic transmission. In some examples, the MUT array can be driven (e.g., by the CMOS circuitry) to beamform the transmitted and/or the received ultrasonic waves. In some examples, the one or more MUT arrays can be configured to generate haptic feedback via the flexible band.

Abstract: An electronic device may include a device housing and a haptic actuator carried by the device housing and that includes a haptic actuator housing and a field member movable within the haptic actuator housing. The electronic device may also include a motion sensor carried by the device housing to sense motion of the field member, an audio sensor carried by the device housing to sense audio noise from the haptic actuator, and a controller coupled to the haptic actuator, the motion sensor, and the audio sensor. The controller may be configured to drive the haptic actuator based upon sensed motion of the field member and audio noise from the haptic actuator.

Abstract: An electronic device may include a device housing and a haptic actuator carried by the device housing and that includes a haptic actuator housing and a field member movable within the haptic actuator housing. The electronic device may also include a motion sensor carried by the device housing to sense motion of the field member, an audio sensor carried by the device housing to sense audio noise from the haptic actuator, and a controller coupled to the haptic actuator, the motion sensor, and the audio sensor. The controller may be configured to drive the haptic actuator based upon sensed motion of the field member and audio noise from the haptic actuator.

Abstract: An electronic device may include a housing and at least one coil carried by the housing. The electronic device may include a field member that includes a magnetic body having a shaft-receiving passageway therein, and at least one bearing within the shaft-receiving passageway. A shaft extends through the at least one bearing and coupled to the housing to permit reciprocal movement of the field member along the shaft and within the housing responsive to the at least one coil. A controller may be capable of powering the at least one coil to move the field member after a threshold period of non-movement.

Abstract: An electronic device may include a housing and at least one coil carried by the housing. The electronic device may include a field member that includes a magnetic body having a shaft-receiving passageway therein, and at least one bearing within the shaft-receiving passageway. A shaft extends through the at least one bearing and coupled to the housing to permit reciprocal movement of the field member along the shaft and within the housing responsive to the at least one coil. A controller may be capable of powering the at least one coil to move the field member after a threshold period of non-movement.