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Tendon routing and anchoring for cableriven single-t surgical manipulators 193

application in minimally invasive osseous tumor removal. Through the project, we have
built a compact, minimally invasive surgical device. We explored different methods of
manufacturing the guides as well as studied their effects on the flexibility of the spring stem.
Manufacturing of the guides at such small dimensions of 3 mm was a challenge, which we
overcame by designing our own customized set of tools and drilling system. Once the
complete end-effector comprising of the spring backbone, instrument head, actuating
tendons, and guides were assembled, the slave-side tools for our device were complete. The
master-side control architecture was using inputs from the joystick and translating them into
servo motor commands to move the spring flexibly. A potential improvement now includes
adding haptic force feedback and additional degrees of freedom, which will add on to the
functionality of the device. With our robot, we are suggesting the following surgical
procedure: using a high-power burr, create a small cavity (B15 mm in diameter) on the
bone surface from the opening created; the robot will be inserted into the cavity for a
biopsy; direct the robot arm to the tumor site; using the forceps, grab a piece of a tumor and
cut it with the electrocautery arm.

Future work can be on four fronts. First, the modularization of the instrument channels
accommodates the switching of instruments during the surgical procedure. Second,
improvements can be made to the user interface of our overall system to ensure intuitive
controls and repeatability of our system. Third, we wish to integrate more degrees of
freedom into our robotic system. Currently, our surgical instruments are capable of bending
motions but are incapable of translational and linear motions. Integrating these extra
degrees of freedom can offer more dexterity and working space for the surgeon during the
procedure. Lastly, the successful integration of variable stiffness into our system can offer
better control, accuracy, and efficiency of the surgical procedure.

Acknowledgments

This work was in part supported by the National Key Research and Development Program, The Ministry of
Science and Technology (MOST) of China (No. 2018YFB1307703).

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