AQUA: An Amphibious Autonomous Robot

AQUA: An Amphibious Autonomous Robot

AQUA, an amphibious robot that swims via the motion of its legs rather than using thrusters and control surfaces for propulsion, can walk along the shore, swim along the surface in open water, or walk on the bottom of the ocean. The vehicle uses a variety of sensors to estimate its position with respect to local visual features and provide a global frame of reference.

The aquatic environment is almost ideal for autonomous robot development. First, it provides a range of real tasks for autonomous systems to perform, including ongoing inspection of reef damage and renewal, tasks in the oil and gas industry, and aquaculture. Second, operating in the water requires robust solutions to mobility, sensing, navigation, and communication.
A common theme of many industrial aquatic tasks is site acquisition and scene reinspection (SASR). Figure 1 shows AQUA performing a typical SASR task, in which it walks out into the water under operator control and is directed to a particular location where it will make sensor measurements. Once near the site, the robot achieves an appropriate pose from which to undertake extensive sensor readings. After making the measurements, the robot returns home autonomously. Later, the robot autonomously returns to the site to collect additional data.