Development of New End-Effector for Proof-of-Concept of Fully Robotic Multichannel Biopsy

This paper presents a novel end-effector designed for a teleoperation type robotic system to perform automated sampling for needle biopsies. The objectives of the robotic system are to realize teleoperation control of the pose and position of the biopsy instrument to reduce X-ray exposure and enhance the precision and accuracy of the procedure as well as to automate the sequence of multiple samplings during the biopsy. In order to realize the desired functions, the end-effector comprises three modules: the needle cartridge, needle positioning mechanism, and needle driving unit. The detachable needle cartridge contains six needle sets: one guide needle and five sampling needles. It rotates itself to change needles and rotates the needle body to adjust the facing angle of the needle tip. The needle positioning mechanism is spherical with two degrees of freedom and is a modification of the typical hemisphere type. The needle driving unit controls the needle grab/release and insertion/retreat motions. A concept design and prototype were developed with an experimental master-salve system for the teleoperation. The experimental results successfully demonstrated the feasibility of the robotic biopsy procedure.