![](bg6.png)
of the focal length estimations is shown in Figure 6
(the pixel is almost the same in
u and v directions on
the image sensor).
Figure 5: Image trajectory during the autocalibration
Figure 6: Convergence of the estimated focal lengths
8 CONCLUSIONS
We proposed a new method for combining visual
and force information which allow us to update the
intrinsic parameters during the task by using an
autocalibration approach. The visual-force control
system has others original aspects which improve
the behaviour of the system. Within these aspects we
should mention the variable weights applied to each
sensor (depending on the GLR parameter) and the
possibility of managing contradictory control
actions. As the results show, the robot is able to
track the image trajectory maintaining a constant
force with the workspace using visual and force
information simultaneously.
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8,8
8,5
8,2
8
7,8
7,5
10 20 30 40
Iterations
mm.
v
ADAPTIVE VISUAL-FORCE CONTROL IN UNKNOWN WORKSPACES
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