BACKGROUND

Robot-assisted surgery (RAS) systems help surgeons performing accurate operations, but a number of drawbacks render them not yet suitable for clinical theaters and procedures. In this paper, a novel vision guided robotic system is proposed to facilitate navigation procedures.

METHODS

A vision guided hybrid robotic system is designed, consisting of a passive serial arm and an active parallel frame. Navigation is accomplished in three steps: approaching, aiming and insertion. First, the target is safely approached with the passive arm. Second, the trajectory is automatically aligned using the parallel frame. And then the target is reached by manual insertion. A stereo camera is used to position fiducials, the robot and the surgical tool. It also provides working area images for professional surgeons at a remote site.

RESULTS

The prototype system accomplished phantom and animal trials with satisfactory accuracy. The robot can easily be adjusted to avoid obstacles and quickly set up on an optimal 'approaching' place. The surgical tool is automatically aligned with the trajectory. The system can withdraw from the working area and restore the aiming posture freely. With the help of the working area images, some important navigation steps can be handled remotely.

CONCLUSIONS

A novel vision guided robotic system is proposed and validated. It enables surgeons to fit the system to the clinical theater. System safety and feasibility are enhanced by multi-step navigation procedures and remote image monitoring. The system can be operated easily by general clinical staff.