A haptic system is described. The haptic system includes a linear resonant actuator (LRA), a receiver, and a transmitter. The LRA has a characteristic frequency and provides a vibration in response to an input signal. The receiver is configured to sense received vibration from the LRA. The transmitter is configured to provide the input signal to the LRA. The receiver is coupled with the transmitter and provides vibrational feedback based on the received vibration. The input signal incorporates the vibrational feedback.

In a driver for a piezo-electric transducer, when a converter circuit and a sensing circuit are the same circuit, many limitations exist on the accuracy of the sensing, due to multiple parasitic effects arising from the interconnection of the power devices. These limitations may limit viability of the sensing for many applications, in particular an accurate determination of when the force on the piezo-electric transducer is fully removed. Providing an additional switch in the sensing circuit configured to repeatedly zero the sensed voltage across the piezo-electric transducer each time the sensed voltage reaches a threshold voltage generates a plurality of voltage segments between zero and the threshold voltage. Accordingly, a controller may then be configured to generate a digital reconstruction of the sensed voltage across the piezo-electric transducer by adding the plurality of voltage segments.

A device, comprising: a pair of force sensors located for detecting a user squeeze input; and a controller operable in a squeeze detection operation to detect the user squeeze input based on a cross-correlation between respective sensor signals originating from the pair of force sensors.

An electronic device has a keyboard with an internal membrane. The membrane has a set of strain gauges configured to respond to a key press, such as when a collapsible dome collapses into contact with the membrane. The strain gauges are connected in a half Wheatstone bridge configuration and are positioned on the membrane in order to limit effects of temperature and subtle flexure of the membrane. The strain gauges are also configured to magnify detection of a resistance differential when a keycap is pressed with sufficient force.

A three-dimensional (3D) haptic keyboard and palm rest experience system for an information handling system may comprise a display device displaying an avatar image located within a virtual 3D gaming environment generated by a gaming application, a processor determining an action involving the avatar image is being displayed, and a position of the action within the virtual 3D gaming environment, a keyboard controller identifying a haptic region of a keyboard and palm rest assembly having a location with respect to the user that correlates to the position of the action within the virtual 3D gaming environment, and the keyboard controller applying a change in voltage, via a printed circuit board assembly, across a piezoelectric actuator disposed beneath the haptic region to cause haptic movement in the haptic region correlated to the position of the action displayed within the virtual 3D gaming environment.

A method of assessing a user input at a virtual button of a user-input system includes: (A) configuring at least one force-measuring device including a plurality of piezoelectric micromechanical force-measuring elements (PMFEs); (B) configuring a cover layer of the user-input system including coupling the force-measuring device(s) to the cover layer at respective positions that are laterally displaced from a center point of the virtual button; (C) receiving, by each respective signal processor, the voltage signals from the PMFEs (PMFE voltage signals); (D) obtaining force-trend data from the PMFE voltage signals; and (E) assessing a user input in accordance with the force-trend data. Each of the PMFEs is configured to output voltage signals to the respective signal processor in accordance with a time-varying strain at the respective PMFE.

A haptic keyboard of an information handling system may include a coversheet to identify a key location of the haptic keyboard; a support layer; a contact foil placed between the coversheet and support layer; a piezoelectric element placed between the contact foil and support layer to receive an applied mechanical stress at the key location of the coversheet and generate an electric actuation signal; and a controller of the information handling system operatively coupled to the contact foil to: receive an electric actuation signal from the piezoelectric element placed under the mechanical stress via the contact foil; and send an electrical response signal to the piezoelectric element to cause the piezoelectric element to generate haptic feedback at the key location.

In a method of using an ultrasonic sensor comprising a two-dimensional array of ultrasonic transducers, a plurality of ultrasonic signals are transmitted according to a beamforming pattern at a position of the two-dimensional array. The beamforming pattern focuses the plurality of ultrasonic signals to location above the two-dimensional array, wherein the beamforming pattern identifies ultrasonic transducers of the two-dimensional array that are activated during transmission of the ultrasonic signals, and wherein at least some ultrasonic transducers of the beamforming pattern are phase delayed with respect to other ultrasonic transducers of the beamforming pattern. At least one reflected ultrasonic signal is received at the position according to a receive pattern, wherein the receive pattern identifies at least one ultrasonic transducers of the two-dimensional array that is activated during the receiving. The transmitting and the receiving are repeated at a plurality of positions of the two-dimensional array.

A system is for detecting a location of a touch input on a surface of a propagating medium. The system includes a transmitter coupled to the propagating medium and configured to emit a signal. The signal has been allowed to propagate through the propagating medium and the location of the touch input on the surface of the propagating medium is detected at least in part by detecting an effect of the touch input on the signal that has been allowed to propagate through the propagating medium. The system includes a piezoresistive sensor coupled to the propagating medium. The piezoresistive sensor is configured to at least detect a force, pressure, or applied strain of the touch input on the propagating medium.

An apparatus may include an input surface, a plurality of key positions on the input surface, a force sensor positioned underneath the input surface at at least one of the key positions, and a proximity controller in communication with a capacitance measuring circuit incorporated into the apparatus.