• Dr. Francis Valentinis
  • Defense Science and Technology Organization (DSTO)
  • 104D Surge Building
  • 4:00 p.m.
  • Faculty Host: Dr. Leigh McCue-Weil

In any engineering design process, the perspective from which a design is viewed can have a significant impact on the degree of success of the result. In this seminar, a novel controller design for tracking of orientation and speed of an under-actuated slender-hull unmanned underwater vehicle (UUV) will be described. Rather than tracking the variables of interest directly, the energy of the system will be shaped in order to achieve the desired result. The control technique used is based on Port-Hamiltonian theory, an approach that can be closely related to bond graph theory, which is used for modeling of multi-domain system dynamics. In the control design presented, the target dynamics (desired dynamic response) is shaped with particular attention to the target mass matrix so that the influence of the un-actuated dynamics on the controlled system is suppressed. This results in achievable dynamics independent of uncontrolled states. Throughout the design, insight of the physical phenomena involved is used to propose the desired target dynamics.  This approach is taken further in some subsequent examples.  Firstly, it will be demonstrated how a further change of coordinates can lead to a control design featuring integral action. Subsequently, some preliminary results will be described showing how guidance control for the under-actuated vehicle can be achieved.