Robotic System for Craniotomy

In this project, I collaborated in design, optimization and prototyping of a haptic robot for craniotomy surgery, which is capable of perforating and cutting the bone flap without restraining the surgeon. This robotic system consists of three degrees-of-freedom for active control of the tool and four passive degrees for positioning and orientation of the active mechanism. For the purpose of optimization, the target workspace is estimated by 3D modeling of the sample skull and bone flaps of targeted surgeries. The design utilizes a parallel remote center of motion mechanism. Coordinating the remote center of motion of the mechanism with the center of a sphere which circumscribes the skull ensures that the milling tool is always nearly perpendicular to the skull bone.

Results indicate that the prototype is able to exert the required forces for bone milling. To decrease the surgeon workload which is one of the goals of the robotic system, a weight compensation algorithm is utilized. Measuring the user forces while the tool is moving in free space shows the success of the algorithm in compensating for gravity forces. Moreover, a virtual wall ability is introduced in the control design to prevent the tool from reaching and damaging the soft tissue under skull bone.

Publication:

• Dehghani M, Alamdar A, Mohammadi Moghadam M. Robot Assisted Craniotomy: development of TMU-CRS and feasibility study on cattle scapula milling. in preparation