Underwater Robots - Gianluca Antonelli.pdf

e.e. position error [m]
0.02
0.01
0
−0.01
−0.02
0 10 20 30 40 50
time [s]
e.e. orientation error [-]
2
0
−2
x 10 −5
0 10 20 30 40 50
time [s]
Fig. 6.24. Case study n. 4. End-effector position/orientation errors
6.7 Conclusions
x
y
2
z
6.7 Conclusions 139
With aview to implementing autonomous missions of robotic systems, kinematic
control plays an important role. The manipulation task isnaturally
defined inthe operational space. Amapping between the task space and the
vehicle/joint space is then necessary to achieve the desired task.
If this mapping isimplicitly performed via amodel based dynamic control
the natural redundancy of the system is not exploited, e.g., is not possible to
take into account additional constraints. Moreover dynamic compensation of
underwater robotic systems is difficult to obtain. On the other hand, off-line
planning of the vehicle/joint positions isnot advisable, since the mission has
to be accomplished in an unstructured, generally unknown, environment. For
these reasons real-time kinematic control seems to be the right approach to
motion control of UVMSs.