Page 272 - Flexible Robotics in Medicine

Comparative mechanical analysis for flexible bending manipulators 261

Figure 11.14
Shear stress simulation for one-piece design.

Figure 11.15
Shear stress versus deformation for one-piece design (without torque, x-axis in mm and y-axis
normalized in the software).

design is slightly larger than the disk-wire design, but the difference is quite small
compared with the deformation (less than 5%, Fig. 11.13).
For the one-piece design, the whole manipulator is using one piece of flexible material.
The center hole is reserved for future surgical use. The whole manipulator is acting as a
backbone; there is no extra support since the flexible material will go back to its
original position when there is no force applying on the top of the manipulator.

The bending motion is the same as the general tendon-driven manipulator. It is controlled
by the length of the driven tendon and the guiding hole position. The force needed to
control the manipulator depends on the materials. The supporting backbone and driven
tendon are two independent systems.