Joseph Palmowski, MS1, Crystal Krause, PhD2, Dmitry Oleynikov, MD2, Shane Farritor, PhD1. 1University of Nebraska Lincoln, 2University of Nebraska Medical Center
OBJECTIVE: Minimally-invasive surgery has become increasingly common in a wide variety of surgical procedures, but it is not without limitations, including limitations to instrument motion and a reduction in dexterity. New developments in surgical robotic technology can help address the limitations of minimally-invasive surgery. We have developed an in vivo, single-arm surgical robot with a compact, dexterous wrist that is able to be independently inserted through a trocar.
DESCRIPTION: Our surgical robot is a one-armed prototype with a three degree-of-freedom (DOF) wrist end-effector and compact, in-line joint to allow for a smaller robot profile. The design features an ex vivo motor housing of three, 12 mm motors, leading to the in vivo components of the robot that include a triple concentric shaft assembly driving a three degree-of-freedom compact shoulder joint providing the yaw, pitch, and roll components of motion of the robot. The upper arm houses a single 6 mm motor, driving the elbow joint activation. The most distal segment of the robot is the forearm/wrist, consisting of three additional 6 mm motors and triple-concentric shaft assembly driving a 3 DOF joint, capable of 90° of tool articulation in either direction. The in vivo portion of the arm fits into a custom trocar with an 18.1 mm internal diameter. The custom trocar was assembled from a 10-15mm Versaseal™ trocar, with a specially-designed, 3D printed cannula component with an internal diameter of 18.1 mm to facilitate smooth passage of a single-arm robot.
PRELIMINARY RESULTS: Our robotic device has a total independent workspace of 7250 cm3 and a shared workspace of 5100 cm3 in a dual, adjacent arm configuration. Virtual simulation was done using V-REP robotics software and a remote programming interface to connect the robot to GeoMagic Touch controllers for manipulation, which allowed the visualization of the capabilities of the wrist.
DISCUSSION: Most surgical procedures require complex, asymmetric maneuvers, and thus robotic arms with mirrored functionality that are positioned as a single body can be a limitation to surgical mobility. This single-armed surgical robot prototype allows for independent gross positioning capabilities, and mobility of this prototype can be improved by the addition of gross positioning capabilities. Furthermore, a robotic platform consisting of multiple independent arms presents the ability to position the arms in various locations around the abdomen across multiple incisions. This is important in that human anatomy can significantly vary from patient to patient and influences the required location of surgical tools and accessories. The use of a trocar to insert the robotic arm offers increased mobility with independently-actuated, gross positioning systems.
Figure 1. Laparoscopic single-arm robot with a compact, dexterous wrist, shown (A) inserted into the custom trocar and (B) virtual simulation of the wrist capabilities using the Geomagic Touch controller.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 91272
Program Number: ETP884
Presentation Session: Emerging Technology iPoster Session (Non CME)
Presentation Type: Poster