Underwater Robots - Gianluca Antonelli.pdf

3.9 Numerical Comparison Among the Reduced Controllers 77
3.9.2 Conclusions and Extension to UVMSs
In this Chapter six controllers have been compared with respect to their
behavior in presence ofmodeling uncertainty and presence ofocean current.
It is shown that, with anot propercompensation,the integral/adaptive action
acts asadisturbance during the transients.
Numerical simulations better illustrate the theoretical results. However,
an aspect tobeconsidered for proper analysis ofthe simulations is that,
despite any effort to chose the gains soastoensure similar performance to
the controllers has been made, this is impossible in astrict sense. Therefore,
the presented results have to be read mainly by looking at the error behavior
rather then focusing on strict numeric comparison. Notice, however, that the
control effort is very similar for all the controllers, meaning that different
behaviors are not given by adifferent magnitude of the inputs.
The extension of these considerations to dynamic control of UVMSs is
straightforward usingthe virtualdecompositionapproachasdetailed in Subsection
7.9.3.