Autonomous Suturing

Background: In single-port access surgeries, robot size is crucial due to the limited space. Thus, a robot may be designed underactuated. Suturing, in contrast, is a complicated task and requires full actuation. This study aims to overcome this shortcoming by implementing an optimization-based algorithm for autonomous suturing for an underactuated robot. Methods: The proposed algorithm approximates the ideal suturing trajectory by slightly reorienting the needle while the deviation of the needle with ideal suturing remains as minimized as possible. The deviation of the path taken by a custom robot with respect to the ideal trajectory varies, depending on the suturing start location within the workspace as well as the needle size. Results: A quantitative analysis reveals that in 13% of the investigated workspace, the accumulative deviation was less than 10 mm. In the remaining workspace, the accumulative deviation was less than xx mm. Likewise, the accumulative deviation of a needle with radius of 10 mm was 2.2 mm as opposed to 8 mm when the radius is 20 mm. Conclusions: The optimization-based algorithm maximized the accuracy of a four-DOF robot to perform a path-constrained trajectory and illustrates the accuracy-workspace correlation.