Virtual-Fixtures Based Shared Control Method for Curve-Cutting With a Reciprocating Saw in Robot-Assisted Osteotomy

In mandibular angle split osteotomy (MASO), prominent mandibular angles need to be cut off with saws such as reciprocating saws. Compared to traditional-freehand methods, robot-assisted methods provide potentials for better cutting performance. In the robot-assisted mandibular angle split osteotomy (RAMASO), a cutting method based on shared control is proposed along with an optimization-planned osteotomy curve. Experimental verification using planes and skull phantoms were conducted and discussed for evaluation of accuracy and safety. The results in 7 cutting experiments for the following error were mainly within 0.76mm and -1.00mm (Q3 +/- 1.5*IQR), peaking at 1.80 mm. The maximum of time-consuming was 304.0s, with the average human robot interactive force reaching around 3.3 N. Experiments indicate the proposed method achieves better performance in accuracy and efficiency compared with the free hand.