Points-based Visual Servoing with Central Cameras - Visual Servoing via Advanced Numerical Methods - page 296

(a) (b)

1

0.15

0

0.1

−1

0.05

−2

−3

0

−4

−0.05

−5

−0.1

−6

−7

200 400 600 800 1000 1200 1400 200 400 600 800 1000 1200 1400

(c) (d)

0.5

0

0.4

0.3

0.2

−50

0.1

0

−0.1

−100

−0.2

−0.3

−0.4

−0.5 −150

200 400 600 800 1000 1200 1400 200 400 600 800 1000 1200 1400

(e) (f)

Fig. 16.4 B , 2 1/2 D visual servoing: (a) initial image; (b) desired image and image-points
trajectories; (c) translational velocities in m / s ; (d) rotational velocities in deg / s ; and (e) error
vector components

ρ i (which appears in the interaction matrix (16.11)) are set to a constant values
ρ i = ρ i (where

ρ i denotes the estimated value of

ρ i at the desired configuration).
Consequently, the points trajectories are no more straight lines until around the 300 th
iteration (where ρ i ). After the 300 th iteration, one can ob-

serve that the errors are decreasing exponentially and the image trajectories became
roughly straight.
The results obtained with the hybrid control B , C and D are shown in Figures
16.4, 16.5 and 16.6 respectively. The parameter

ρ i became very close to

ρ is set to ρ = 2 ρ in those cases.