3.4 6 DOF adaptive control



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3.4 6 DOF adaptive control

  
Figure 9: Average final endpoint error/feature (left), and deviation from straight line trajectory in feature space (right) for a 16 tracked features and 6 controlled DOF problem

When controlling the full 6 DOF of the manipulator we do not get quite the same robustness against model errors as in the 3 DOF case. Model errors worse than yield a significant and increasing proportion of divergent trials. To get near convergence we needed to restrict to be or above. In a test of 50 trials in this range, two did not converge. One showed oscillatory behavior, and the other diverged immediately. In this experiment we ran the controller to its convergence limit rather than halting at a fixed accuracy. A remarkable of the trials with the best model achieve zero final visual error. This is down to when the model error is . In general, average visual endpoint errors as well as trajectory errors remain low even at low model accuracies, as can be seen in fig. 9.



jag@cs.rochester.edu