Magnetic Trackers: Robot Control and Vasculature Imaging - Microsurgery: Advances, Simulations, and Applications - page 229

working space, similar to the X-rays device mounted on the C arm
in IVR environment. The irst DOF is linear, allowing reciprocation
of the camera along the endovascular surgery simulator. The second
DOF is an arch mounted over the DOF1, this allows changing the
pitch angle of the camera. The third DOF allows rotating the camera
along the arch, changing the yaw angle of the camera (Fig. 7.3).

Pan

Tilt

Camera

a)

b)

Reciprocation

Surgical bed for
endovascular
surgery simulaion

d)

c)

Figure 7.3 (a) Belt system of reciprocation motion of surgical bed. (b)

Worm gear system to rotate arch of surgical bed. (c) Chain
and sprocket for camera panning. (d) Robotic camera with
three degrees of freedom for interventional radiology images
simulation.

The selected mechanism for DOF1 is a belt system and a linear
motion rail. A servo motor rotates one of the shafts of the belt
system to reciprocate the arch at 0.012 mm/step over the bed
surface. DOF2 is a worm gear mechanism to tilt the arch with a
resolution of 0.002 deg/step. A damper was added to the shaft
of the arch to reduce the oscillation produced by the intrinsic
properties of the worm gear. Such gear system increases the
torque and allows fixing the arch position while the system is
turned off. DOF3 enables panning the camera along the arch. A
roller cart is attached a motor and a camera, enabling the camera
to move along the arch using chain and sprocket system. The chain
was inserted on a canal opened in the upper surface of the arch.