A marine sonar display device comprises a display, a memory element, and a processing element. The processing element is configured to transmit a transmit electronic signal to a frequency steered sonar element that transmits an array of sonar beams into a body of water in a first direction towards the front of the marine vessel forming a first sonar wedge and a second array of sonar beams into a body of water in a second direction directly below the marine vessel forming a second sonar wedge, receive a receive electronic signal from the frequency steered sonar element, generate an array of sonar image slices, identify a gap in an underwater area between the first sonar wedge and the second sonar wedge, and control the display to visually present the array of sonar image slices in near real time and a sonar image slice in the gap.

In a method and system for inspecting the condition of a structure, the structure is scanned with a three-dimensional (3D) scanner. The 3D scanner includes a sensing system having one of a radar sensing device or an ultrasonic detection device. The sensing system detects 3D information about a subsurface of the structure, and the 3D scanner generates 3D data points based on the information detected by one or more of the radar sensing device and the ultrasonic detection device. A 3D model is constructed from the 3D data and is then analyzed to determine the condition of the subsurface of the structure.

A device for detecting obstacles that is wearable by a subject, for example integrated in an item of footwear. The device includes an ultrasound source for emitting an ultrasound transmission signal and an ultrasound receiver for receiving a corresponding ultrasound signal reflected by an obstacle, a control module for measuring a time of flight between emission of the ultrasound transmission signal and reception of the corresponding ultrasound signal reflected by the obstacle and calculating, on the basis of the aforesaid time of flight, the distance at which the obstacle is located. The device comprises an inertial sensor, in particular an acceleration sensor, designed to measure acceleration of the foot along three axes, and a control module configured for enabling operation of the ultrasound source if the aforesaid acceleration values measured by the inertial sensor respect a given condition for enabling measurement of the time of flight.

A device for detecting obstacles that is wearable by a subject, for example integrated in an item of footwear. The device includes an ultrasound source for emitting an ultrasound transmission signal and an ultrasound receiver for receiving a corresponding ultrasound signal reflected by an obstacle, a control module for measuring a time of flight between emission of the ultrasound transmission signal and reception of the corresponding ultrasound signal reflected by the obstacle and calculating, on the basis of the aforesaid time of flight, the distance at which the obstacle is located. The device comprises an inertial sensor, in particular an acceleration sensor, designed to measure acceleration of the foot along three axes, and a control module configured for enabling operation of the ultrasound source if the aforesaid acceleration values measured by the inertial sensor respect a given condition for enabling measurement of the time of flight.

During transmission, a speed of sound pulses gradually reduces due to acoustic impedance. Regulating a length or a density or a sound speed of the sound pulses affects their average speed in the transmitting medium, sound intensity and detecting depth. Time of flight (TOF) and TOF shift can be used to calculate the depth and moving speed of detecting objects. Calculating a speed of moving objects by simultaneously detecting TOF shift at same site from two separated piezoelectric (PZT) elements improves the testing results with accuracy, simplification and reproducibility. Coding sound pulses to obtained the TOF and the TOF shift will simultaneously calculate the depth and the moving speed of sampling points, which can be used to construct 2D and 3D images for these motionless and/or moving sampling points. Coded sound pulses also improves the quality of the imaging.

During transmission, a speed of sound pulses gradually reduces due to acoustic impedance. Regulating a length or a density or a sound speed of the sound pulses affects their average speed in the transmitting medium, sound intensity and detecting depth. Time of flight (TOF) and TOF shift can be used to calculate the depth and moving speed of detecting objects. Calculating a speed of moving objects by simultaneously detecting TOF shift at same site from two separated piezoelectric (PZT) elements improves the testing results with accuracy, simplification and reproducibility. Coding sound pulses to obtained the TOF and the TOF shift will simultaneously calculate the depth and the moving speed of sampling points, which can be used to construct 2D and 3D images for these motionless and/or moving sampling points. Coded sound pulses also improves the quality of the imaging.

Distance detection method and device are provided. The distance detection method comprises: providing a directional signal emitting module; providing a directional signal receiving module having a constant bandwidth; providing a distance detection signal to the directional signal emitting module; changing a frequency of the distance detection signal provided to the directional signal emitting module, and judging whether the directional signal receiving module can decode a reflected directional signal into a received signal; and judging a distance between an external object and the directional signal receiving module according to whether the received signal corresponding to the frequency of the distance detection signal can be decoded.

An ultrasonic device includes a substrate, a transmitter provided at the substrate and configured to transmit an ultrasonic wave to an object, and a receiver provided at a position different from the transmitter at the substrate and configured to receive an ultrasonic wave reflected by the object. A resonance frequency of the transmitter is higher than a resonance frequency of the receiver. An anti-resonance frequency of the receiver is included in a predetermined frequency band including the resonance frequency of the transmitter.

An object detection device which determines an amplitude A.sub.r of an ultrasonic wave received by a receiving unit, detects a frequency f.sub.r of the ultrasonic wave, sweeps a frequency f.sub.p of a pulse signal after a predetermined time has elapsed from start of generation of the pulse signal, and determines that the received ultrasonic wave is a reflected wave of the probe wave when the frequency f.sub.r after the amplitude A.sub.r becomes a predetermined reference value or more from start of transmission of the probe wave makes the same change as the frequency f.sub.p. When an ultrasonic wave received by a receiver is determined to be a reflected wave of the probe wave, the object detection unit calculates a distance to an object based on a time from transmission of the probe wave to reception of the ultrasonic wave.

The invention is based on speed changes of sound/ultrasound pulses and a fixed detecting depth between a transducer and sampling points to collect information of the detecting depth and/or a velocity of motionless and/or moving objects from the sampling points to construct two-dimension or three-dimension images of the sampling points. By taking advantages of a pulse ultrasound and a continuous ultrasound, a method of coded sound pulses can simultaneously collect the information of the detecting depth and the velocity from the sampling points, which improves imaging quality. Calculating a speed of the moving objects by simultaneously detecting time-of-flight (TOF) and TOF shift at same site from two separated piezoelectric (PZT) elements improves testing results with accuracy, simplification and reproducibility. An aliasing can be rectified based on the TOF and the TOF shift.