Page 180 - Human Inspired Dexterity in Robotic Manipulation

178 Human Inspired Dexterity in Robotic Manipulation

,
θ zd vir component of the orientation of the desired virtual-object frame, R d vir
expressed in terms of XYZ Euler angles. These figures illustrate that x d vir
are updated in a step-like pattern with every visual image acquisi-
and R d vir
tion interval. Fig. 9.8 shows snapshots from the simulation. In this figure,
both the measured and virtual frames simultaneously approach and finally
converge to their desired values.

Object position x and virtual position x vir (m) 0.1 0 xd vir
0.2
xd
x

xvir

–0.1
0 2 4 6 8 10
Time (s)
Fig. 9.6 Transient responses of the x components of the position of the measured-
object frame, x; the position of the virtual-object frame, x vir ; and the position of the
, when the control inputs u p and u o are used, where
desired virtual-object frame, x d vir
the sampling rate is h ¼ 20 Hz and the time delay due to the computational cost of
image processing and the latency of data transmission is t image ¼ 50 ms.

40
µ
zd
µ
z
Object orientation µ z and virtual orientation µ z vir (degrees) 20 0 µ zd vir
µ
z vir

–20
0 2 4 6 8 10
Time (s)
Fig. 9.7 Transient responses of the θ z component of the orientation of the measured-
component of the orientation of the virtual-object frame,
object frame, R, and the θ z vir
R vir , expressed in terms of XYZ Euler angles when the control inputs u p and u o are used,
where the sampling rate is h ¼ 20 Hz and the time delay due to the computational cost
of image processing and the latency of data communication is t image ¼ 50 ms.