A portion of a line from a line laying vessel to a touchdown support point on or near to the seabed is imaged with a 3 dimensional sonar imaging system to produce coordinates of a series of touchdown points using a time sequence of sonar images, and the time series of touchdown points is recorded.

Provided are a sonar system and transducer assembly for producing a 3D image of an underwater environment. The sonar system may include a housing mountable to a watercraft having a transmit transducer that may transmit sonar pulses into the water. The system may include at least one sidescan transducer array in the housing that receives first and second sonar returns with first and second transducer elements and converts the first and second returns into first and second sonar return data. A sonar signal processor may then generate a 3D mesh data using the first and second sonar return data and at least a predetermined distance between the transducer elements. An associated method of using the sonar system is also provided.

An image with the sound speed in reception beamforming being changed is generated with a small amount of calculation. A conversion unit 41 converts first real space image data into first wave number space data in a wave number space. A remapping processing unit 42 processes the first wave number space data to generate data equivalent to second wave number space data. A reconversion unit 43 generates a second real space image by inversely converting data equivalent to the second wave number space data.

An ultrasonic type object detection apparatus sequentially detects a distance between an ultrasonic sensor and an object in a coverage of a transmission wave at a predetermined detection cycle based on a time taken for the ultrasonic sensor to transmit the transmission wave and then to receive a reflection wave. The apparatus includes: a storage storing the distance to the object; a vehicle information acquisition device acquiring vehicle information for calculating a movement distance; a detection distance predictor predicting a next detected distance to the object based on a past detection result and the vehicle information; and a short range determinator determining whether the object is present in a short range area in which the distance between the object and the ultrasonic sensor is equal to or shorter than a short range threshold.

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.

Object detection may include transmitting, by a first device, a first pulse into an environment using a wide field configuration of an ultrasonic sensor array, detecting a presence of an object in the environment based on a detected echo based on the first pulse. In response to detecting the presence of the object, a targeted configuration of the ultrasonic sensor array is determined, and a second pulse is transmitted into the environment based on the second pulse, wherein a characteristic of the object is determined based on a detected echo from the second pulse.

Ultrasonic sensing systems and associated methods provide side-lobe reduction to improve the acoustic detection of small objects, the signature envelope peaks of which can otherwise be obscured by subsidiary envelope peaks in side lobes that result from residual correlation between a signal received by an ultrasonic transducer and a template signal corresponding to a burst signal emitted by the ultrasonic transducer. A shaping signal by which the amplitude of the burst signal can be varied with respect to time is taken into account in the template signal, and correlator circuitry correlates a signal derived from the ultrasonic transducer with the template signal to produce a correlated output exhibiting the desired side-lobe reduction. The distance from the transducer to the detected object can thereby be determined with enhanced accuracy and responsiveness.

Object detection may include transmitting, by a first device, a first pulse into an environment using a wide field configuration of an ultrasonic sensor array, detecting a presence of an object in the environment based on a detected echo based on the first pulse. In response to detecting the presence of the object, a targeted configuration of the ultrasonic sensor array is determined, and a second pulse is transmitted into the environment based on the second pulse, wherein a characteristic of the object is determined based on a detected echo from the second pulse.

An obstacle recognition device, a vehicle system including the same, and a method thereof are provided. The obstacle recognition device includes a storage storing data and an algorithm for calculating a risk probability and a processor configured to execute the algorithm to generate an occupancy grid map based on a sensing value of at least one ultrasonic sensor, calculate the risk probability of each cell on the occupancy grid map, and determine a shape and location of an obstacle based on the risk probability of each cell.

An acoustic detection system for detecting at least partly submerged targets in a sensitive area defined with respect to an infrastructure, the detection system includes at least one multistatic detection group, each multistatic detection group defining a detection area, and comprising: a submerged transmitter emitting at low frequencies; a plurality of submerged receivers comprising at least two receivers, each receiver of a given group forming, with the transmitter of the group, a bistatic pair, each bistatic pair generating an elementary detection area surrounding a blind zone, the detection area of the group being formed by all of the elementary detection areas of the receivers of the group, the receivers being arranged in at least one layer. For at least one group of the system, the form described by the receivers of at least one layer of the group is an at least partly circular form of given radius, the inter-receiver distance between two adjacent receivers of the layer depending on the distance between the transmitter of the group and the rectilinear segment linking the adjacent receivers of the layer, called reference transmitter-receiver distance.