Chirp Microsystems Inc.

Invensense, Inc.

Other

Apple Inc.

Appe Inc.

Mitchell Herman Kline

Richard J Przybyla

David Horsley

Hopil Bae

Joe Youssef

Ryan Young

Chaohao Wang

Chun-Yao Huang

Jun Li

Tien-Chien Kuo

Xiaokai Li

Yingkan Lin

Ivan Knez

Kanghoon Jeon

Bilin Wang

Jose Antonio Dominguez-Caballero

Syed Farhan Mohiuddin

Sebastian Riccardi

David A Horsley

Richard J Przbyla

Cristabel Yang

A device comprises a processor communicatively coupled with an ultrasonic sensor which is configured to repeatedly emit ultrasonic pulses during transmit periods which are interspersed with receive periods. Returned ultrasonic signals corresponding to the emitted ultrasonic pulses are received by the ultrasonic sensor during the receive periods. The processor is configured to direct the ultrasonic sensor to listen, during a listening window, for a potentially interfering ultrasonic signal from a second ultrasonic sensor. The listening window is prior to a transmit period of the transmit periods. In response to detecting the potentially interfering ultrasonic signal during the listening window, the processor is configured to adjust operation of the ultrasonic sensor to avoid an ultrasonic collision with the second ultrasonic sensor to facilitate coexistence of the ultrasonic sensor and the second ultrasonic sensor in an operating environment shared by the ultrasonic sensor and the second ultrasonic sensor.

Ultrasonic device coexistence

Systems and methods for ultrasonic liquid level sensing. A circuit causes an ultrasonic transducer to transmit a sequence of ultrasonic pulses and receive a sequence of reflected signals. Each reflected signal includes at least one first reflection associated with at least one non-moveable surface and at least one second reflection associated with a moveable surface. A digital controller, for each reflected signal: determines at least one of a magnitude and a variance of the respective signal to form at least one output signal, identifies, in the at least one output signal, at least one first pulse indicative of the at least one non-moveable surface and at least one second pulse indicative of the moveable surface, and determines a distance of the moveable surface relative to the at least one non-moveable surface based on the identified first and second pulses.

Ultrasonic liquid level sensing

An ultrasonic transducer device comprises a controller and a differential piezoelectric micromachined ultrasonic transducer with a membrane later, a bottom electrode layer, a piezoelectric layer, and a top electrode layer comprising a first electrode with a positive voltage to displacement coefficient and a second electrode with a negative voltage to displacement coefficient. During a first period, the controller electrically decouples a first output of a first driver from the first electrode, electrically decouples a second output of a second driver from the second electrode, and electrically couples the first and second electrodes to equalize charge between them. During a second period, the controller electrically decouples the first and second electrodes, electrically couples the first output with the first electrode, and electrically couples the second output with the second electrode; where waveforms on the first and second outputs during the second time period are out of phase with one another.

Transmitter charge sharing in a differential ultrasonic transducer

A robotic cleaning appliance includes a sonic transducer and a processor coupled with a housing. The sonic transducer transmits sonic signals toward a surface within its ringdown distance and receives corresponding returned signals. Following cessation of the sonic signals, the processor samples the ringdown signal generated by the sonic transducer during an early portion before the corresponding returned signals have reflected back to the sonic transducer, and during a later portion which includes the corresponding returned signals. The processor utilizes the sampled early portion to estimate a void ringdown signal of which represents performance of the sonic transducer in absence of returned signals being received. The processor compares the estimated void ringdown signal to the later portion of the ringdown signal and generates a metric based on the comparison. The processor utilizes the metric to determine a type of the surface, out of a plurality of surface types.

Surface type detection

An ultrasonic transceiver system includes a transmitter block, a receiver block, a state machine, and a computing unit. The transmitter block contains circuitry configured to drive an ultrasound transducer. The receiver block contains circuitry configured to receive signals from the ultrasound transducer and convert the signals into digital data. The state machine is coupled to the transmitter and receiver blocks and contains circuitry configured to act as a controller for those blocks. The computing unit is coupled to the transmitter block, the receiver block, and the state machine and is configured to drive the transmitter block and process data received from the receiver block by executing instructions of a program. The program memory is coupled to the computing unit and is configured to store the program. The computing unit is configured to be reprogrammed with one or more additional programs stored in the program memory.

Programmable ultrasonic transceiver

Time of flight between two or more ultrasonic transceivers is measured using known delays. First and second transceivers are duty cycled, each having a respective receive period that is less than a measurement period during which the transceivers are configured to receive transmissions. An ultrasonic trigger pulse is transmitted by the first transceiver. The second transceiver, upon receiving the trigger pulse, transmits an ultrasonic response pulse after a first predefined delay time that is known to the first transceiver and greater than the receive period of the second transceiver. Subsequently, the first transceiver receives the ultrasonic response pulse and determines a receive time. The first transceiver determines the distance between the first transceiver and the second transceiver from a speed of sound, an elapsed time between the time of transmission of the trigger pulse and the receive time, and the first predetermine delay time.

Ultrasonic beacon tracking

Methods and systems are disclosed for determining pose information for at least one of a transmitter and receiver, both of which comprise ultrasonic transducers. A relative position is determined between the transmitter and the receiver and an orientation for at least is also determined. After obtaining field of view data for at least one of the transmitter and receiver, a field of view between them is determined, based at least in part on the field of view data, the determined relative position and the determined orientation. The pose information is then determined by weighting measurements of an ultrasonic signal emitted by the transmitter and received by the receiver based at least in part on the determined field of view relationship.

Object-localization and tracking using ultrasonic pulses with reflection rejection

An ultrasonic transceiver system includes a transmitter block, a receiver block, a state machine, a computer unit. The transmitter block contains circuitry configured to drive an ultrasound transducer. The receiver block contains circuitry configured to receive signals from the ultrasound transducer and convert the signals into digital data. The state machine is coupled to the transmitter and receiver blocks and contains circuitry configured to act as a controller for those blocks. The computing unit is coupled to the transmitter block, the receiver block, and the state machine and is configured to drive the transmitter block and process data received from the receiver block by executing instructions of a program. The program memory is coupled to the computing unit and is configured to store the program. The computing unit is configured to be reprogrammed with one or more additional programs stored in the program memory.

A tracking method is disclosed. The method may include displaying visual content on a screen. A base station may be stationary with respect to the screen while the visual content is being displayed. In contrast, one or more objects may move with respect to the screen while the visual content is being displayed. The one or more objects may be tracked so that the movement thereof may be used to alter the visual content. Such tracking may involve the base station and the one or more objects sending and/or receiving one or more ultrasonic pulses. The tracked object also determines information using an inertial sensor assembly that receives a synchronization signal coordinated with the one or more ultrasonic pulses. Time-difference-of-arrival and/or time-of-flight of the one or more ultrasonic pulses may then be used to estimate a relative location and/or a relative orientation of the one or more objects with respect to the base station in three dimensional space, so that the estimate is fused with information determined by the inertial sensor assembly using the synchronization signal.

Three dimensional object-localization and tracking using ultrasonic pulses with synchronized inertial position determination

An ultrasonic transmitter system includes a digital controller, bandpass pulse-width modulator (BP-PWM) unit, a digital to analog converter (DAC), and an ultrasound transducer. The controller generates pulse width and phase reference signals. The BP-PWM configured receives these signals generates a pulse width modulation (PWM) output characterized by a pulse width and a phase based on the pulse width and phase reference signals. The DAC) receives the PWM output from the BP-PWM unit and generates an output characterized by the pulse width and phase. The ultrasonic transducer receives the output from the DAC and generates an output sound pressure in response to the output from the DAC. An amplitude of the RMS sound pressure depends on the pulse width of the output from the DAC.

Quadrature amplitude modulation circuitry for ultrasonic transducer

Aspects of the subject technology relate to displays for electronic devices and methods of operating the displays. The display may include an array of display pixels arranged in rows and columns. A v-drive operation in which rows are alternatingly operated about a center of each of two halves of the display is provided. Data rendering operations are provided that generate a virtual frame rate boost.

Data rendering and driving of electronic device displays

An electronic display may include an active area having a first pixel formed in the active area, where the first pixel emits light in response to image data. The electronic display may also include a controller to transmit the image data to the first pixel. The first pixel may include an organic light-emitting diode that emits the light in response to the image data, memory to digitally store the image data received from the controller, and driver circuitry to receive the image data from the memory. The driver circuitry may cause the organic light-emitting diode to emit the light in response to the image data.

Memory-in-pixel architecture

A tracking method includes displaying visual content on a screen of a head mounted display (HMD). One or more base stations may be stationary with respect to the screen while the visual content is being displayed. In contrast, one or more objects may move with respect to the screen while the visual content is being displayed. Time-difference-of-arrival (TDoA) and/or time-of-flight (ToF) may be measured for one or more ultrasonic pulses transmitted from the base station, one or more objects, or HMD. Position and orientation of the objects and HMD may be calculated based on the TDoA and ToF. Different frequencies of pulses may be used to locate the HMD and the objects. An electromagnetic synchronization signal from the HMD and/or base station may be used to measure TDoA. Position and orientation measurements may be fused with outputs from IMUS (inertial measurement units) to reduce jitter.

Three dimensional object-localization and tracking using ultrasonic pulses

An ultrasound transducer may be driven by a driver circuit having one or more charge pumps and a multi-level inverter. The one or more charge pumps are configured to drive the ultrasound transducer only during output transitions of the inverter.

Efficient on-chip high-voltage driver circuit for ultrasonic transducer

Time of flight between two or more ultrasonic transceivers is measured using known delays between receiving a trigger and sending an ultrasonic pulse in reply. A receive time is measured from a beginning of a receive phase in which the pulse is detected until receipt of an ultrasonic reply pulse. A trip time is determined from a sum of the receive time and a difference between a known first reference period for a transceiver that sends the trigger pulse and a second know reference period for a second transceiver that sends the reply pulse. The second reference period corresponds to a delay between when the second transceiver receives the initial or subsequent trigger pulse from the first transceiver and when the second transceiver sends the reply pulse.

Growing community of inventors

Alameda, CA, United States of America

Mitchell Herman Kline