This paper describes a new sonar system that can perform target localisation in two dimensions and classification into planes, concave corners and convex edges with no extra time overhead. That is, the sensor transmits on two transmitters a short time apart, thereby collecting echoes in virtually the same time as a single transmitter system. Moreover, the time separation of the transmitted puls...

A submarine's sonar team is responsible for detecting, localising and classifying targets using information provided by the platform's sensor suite. The information used to make these assessments is typically uncertain and/or incomplete and is likely to require a measure of confidence in its reliability. Moreover, improvements in sensor and communication technology are resulting in increased am...

This paper addresses a practical problem arising in the calibration of bottom-lock doppler sonar for the navigation of underwater robot vehicles. Employing a least-squares method, the rotational alignment offset between a bottom-lock doppler sonar and a north-seeking gyroscope can be experimentally determinined using sensors commonly deployed with a vehicle in the field. It requires sensor valu...

Multi-sensor sonar tracking has many advantages, such as the potential to reduce the overall measurement uncertainty and the possibility to hide the receiver. However, the use of multi-target multi-sensor sonar tracking is challenging because of the complexity of the underwater environment, especially the low target detection probability and extremely large number of false alarms caused by reve...

The Generic Ocean Array Technology Sonar (GOATS) Joint Research Program is currently exploring the development of sensor-adaptive autonomous underwater vehicle (AUV) technology specifically directed toward rapid environmental assessment and mine countermeasures in coastal environments. As part of the effort, MIT is developing the GOATS multi-static sonar concept with the goal of being able to d...

For mobile robots equipped with incremental encoders and one sonar sensor this paper presents wall-following controllers that achieve global convergence, as well as the fulll-ment of constraints on the orientation of the sonar and the velocities of the wheels. A sensor-fusion approach for the estimation of the robot's coordinates is adopted by designing an Extended Kalman Filter that combines u...

In this paper, we examine a retrodiction approach to handle the out-of-sequence measurement (OOSM) problem in active sonar, for both linear and nonlinear representations of target contact information. We find that the retrodiction approach performs well, even with multiple sensors and multi-lag out-of-sequence measurements. In addition, we examine the impact of the use of a ping-time reference ...

A sonar array and a camera are the sensors of a robot that learns to move inside a building. Learning is based on the association of ultrasonic and visual images with motor commands. The two sensors extract diierent information from the environment. Sonars produce a short-range depth image on the sonar array plane, vision gives a wide-range at image of the space. In this work, a memory-based pr...

This paper describes a new method for determining range information about a robot's surroundings using low resolution ultrasonic sensors. These sensors emit ultra-sound which bounces o of nearby objects and returns to the sensor. The time-ofight for the sound to return to the sensor is the distance between the sensor and the object. A sonar arc represents the possible locations of the object. W...