Design of a Flexible Imaging Probe for Robotics Surgery

Abstract

Minimally invasive surgery assisted by robots has shown higher efficiency and precision. In spite of the good performance of the state of the art surgery robotics systems, the size and number of external incisions required by instruments should be reduced to lower the scarring and incisional pain experienced by the patient. Other important improvement derived from the use of smaller incisions is the diminishment of time required for recovery. This research develops a flexible scope of small diameter driven by segmented multiple actuators to produce a deflection of the imaging probe at its distal end providing better visualization than the current rigid cameras. The research is conducted in cooperation with the Biorobotics Laboratory at the University of Washington USA, where our scope will be incorporated to Raven, a 7-DOF cable-actuated surgical robot. The flexible scope is composed of three segments as illustrated in Figure 1, where it is possible to see that the device contains a ring of cables enclosed externally and internally by two different springs and a semi rigid covering. The main mechanism of bending is the compression and extension of the external spring at the distal end. The change of length in this spring is controlled by an active system that combines pulling and releasing actions through the ring of cables. The device has advantages in its simplicity of actuation and the high elasticity and flexibility at the distal end. In the current state of the project, a testing system is under construction.