Digital ultrasonic scanning system for positioning underwater remotely operated vehicles

Abstract

The design of a digital ultrasonic scanning system for positioning underwater remotely operated vehicles (UROVs) is presented in this paper. Its principle of operation is based on ultrasonic distance measurements (by determining the time of flight) and mechanical scanning. Ultrasonic imaging is used to construct the 3-D image of the environment surrounding the vehicle. The image is then used, in combination with signals coming from a gyroscope, to estimate the actual distances of the vehicle from the objects in the vicinity of the vehicle. The system consists of a 200 KHz point transducer, a scanning transmitter-receiver unit and a computer for image reconstruction and control of the UROV. The main advantages of this system are its simplicity and its accurate large scale measurement capability. The design of the system was carried out in order to conform directly with the computer controlling the UROV, and its operation was experimentally demonstrated.