Control strategies applied to autonomous underwater vehicle for inspection of dams

Abstract

Hydroelectric power plants need to ensure an uninterrupted energy supply. To achieve this objective, activities of maintenance and inspection are done periodically. The use of divers to do these maintenance in submerged areas, implied high risks for them. In this sense, the automated inspection of such facilities through underwater vehicles can be a satisfactory solution. This article presents a comparison between two control techniques applied to underwater vehicle, Feedback Linearization and Sliding Mode.These strategies are responsible to ensure the following two requirements. First, to make the vehicle overcome the velocity gradient caused by dam's water intakes. Second, to follow the desired trajectory. The control laws were tested by analysing their performance in a helical reference trajectory with the presence of disturbance caused by water intakes.

Nonlinear mapping for performance improvement and energy saving of underwater vehicles

“…Due to physical limitations of the DC motor, hard nonlinearities like actuator saturation, Coulomb friction, dead-zones and hysteresis may also be included for a more complete model. Neglecting these effects implies that we can apply Laplace's transformation to Equation (1). Moreover,…”

“…With this combination, we aim to conciliate simplicity to obtain 1 and n and improve the performance using the PI analogy. In this sense, consider that 1 and n values are given by…”

“…For example, the application of autonomous vehicles for underwater inspection becomes an important topic of application. This due to the possibility of monitoring the silting of reservoirs, cracks in the dams, and biological components without need of exposing a diver . The inspection of submerged facilities is increasingly intense, and this has contributed to the scientific advances in underwater robotics.…”

“…This due to the possibility of monitoring the silting of reservoirs, cracks in the dams, and biological components without need of exposing a diver. 1 The inspection of submerged facilities is increasingly intense, and this has contributed to the scientific advances in underwater robotics. Autonomous underwater vehicles (AUVs) have been used increasingly for missions in submerged installations.…”