An ultrasonic detecting device may include a transmitter, a receiver, a motor, and processing circuitry. The transmitter may transmit a sequence including a first pulse wave and a second pulse wave separated by a time interval shorter than a time required for an ultrasonic wave to make a round trip underwater to a detection range. The receiver may convert reflection waves of the first and second pulse waves into echo signals. The motor may rotate the receiver. The processing circuitry may acquire, from the echo signals, a first echo signal and a second echo signal, generate first image data based on the first echo signals and second image data based on the second echo signals, and generate synthesized image data based on an angular position of the receiver when the first image data is generated, and an angular position of the receiver when the second image data is generated.

Spectral components of waves having one or more properties other than phase and amplitude that vary monotonically with time at a receiver, and provide retardations or lags in the variation in proportion to the times or distances traveled from the sources of the waves to the receiver. The lags concern the property values at departure from a source and are absent in its proximity. Orthogonality of the lags to modulated information makes them useful for ranging and for separation or isolation of signals by their source distances. Lags in frequencies and wavelengths permit multiplication of capacities of physical channels. Constancy of the lagging wavelengths along the entire path from a source to the receiver enables reception through channels or media unusable at the source wavelengths, as well as imaging at wavelengths different from the illumination.

Various implementations include a personal sonar system sized to be worn on a body of a user. In some cases, the system includes: at least one acoustic transmitter for transmitting ultrasonic signals into an environment proximate the user; at least two acoustic receivers for receiving return ultrasonic signals from the environment proximate the user; a directional indication system for providing a directional output to the user; and a controller coupled with the at least one transmitter, the at least two acoustic receivers, and the directional indication system, the controller configured to: identify a physical object within the environment proximate the user based on the return ultrasonic signals; and initiate the directional output at the directional indication system based on the identified physical object within the environment.

A method for obstacle detection and recognition for an intelligent snow sweeping robot is disclosed, comprising: 1) disposing ultrasonic sensors at a front end of the snow sweeping robot to detect distance information from an obstacle ahead; and disposing radar sensors at the front and rear of the snow sweeping robot to detect whether a creature suddenly approaches; 2) processing signals detected by each of the ultrasonic sensors and radar sensors, and calculating a forward distance of the snow sweeping robot; and 3) determining a snow cover extent of a working road, detecting a change of the distance from the obstacles, and recognizing the obstacles for conditions of an ultrasonic ranging variation ratio and a variation of the forward distance of the snow sweeping robot, a change of the signal detected by radar sensors, and a descriptive statistic of the snow cover extent within a specific time period.

A method for obstacle detection and recognition for an intelligent snow sweeping robot is disclosed, comprising: 1) disposing ultrasonic sensors at a front end of the snow sweeping robot to detect distance information from an obstacle ahead; and disposing radar sensors at the front and rear of the snow sweeping robot to detect whether a creature suddenly approaches; 2) processing signals detected by each of the ultrasonic sensors and radar sensors, and calculating a forward distance of the snow sweeping robot; and 3) determining a snow cover extent of a working road, detecting a change of the distance from the obstacles, and recognizing the obstacles for conditions of an ultrasonic ranging variation ratio and a variation of the forward distance of the snow sweeping robot, a change of the signal detected by radar sensors, and a descriptive statistic of the snow cover extent within a specific time period.

Various embodiments of the present invention are directed towards a system and methods for generating three dimensional (3D) images with increased composite vertical field of view and composite resolution for a spinning three-dimensional sensor, based on actuating the sensor to generate a plurality of sensor axis orientations as a function of rotation of the actuator. The output data from the sensor, such as a spinning LIDAR, is transformable as a function of the actuator angle to generate three dimensional imagery.

Various embodiments of the present invention are directed towards a system and methods for generating three dimensional (3D) images with increased composite vertical field of view and composite resolution for a spinning three-dimensional sensor, based on actuating the sensor to generate a plurality of sensor axis orientations as a function of rotation of the actuator. The output data from the sensor, such as a spinning LIDAR, is transformable as a function of the actuator angle to generate three dimensional imagery.

A survey system including a multibeam echo sounder having a single projector array and a single hydrophone array constructs a multi-signal message and deconstructs a corresponding multi-signal echo to substantially simultaneously perform multiple survey missions.

A micromachined ultrasonic transducer (MUT). The MUT includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode and an asymmetric top electrode is disposed on the piezoelectric layer. The areal density distribution of the asymmetric electrode along an axis has a plurality of local maxima, wherein locations of the plurality of local maxima coincide with locations where a plurality of anti-nodal points at a vibrational resonance frequency is located.

A method for use in acoustic imaging, comprising: transmitting, from a transmitter, a first sound wave pulse at a first frequency determined by a maximum sampling rate of a receiver; transmitting at least one second sound wave pulse at a frequency substantially equal to the first frequency, the first and at least one second sound wave pulses being transmitted substantially within a fraction of a sample interval of the receiver; receiving and sampling, at the receiver, a reflection of at least two of the first and at least one second pulses to generate a set of receiver samples; and expanding the set of receiver samples, based on the first frequency and a total number of the first and at least one second pulses transmitted, to generate an expanded sample set with a larger number of samples than the set of receiver samples.