Design and Experimental Validation of a Novel Hybrid Robot for Fibula Osteotomies in Mandibular Reconstruction Surgery

Abstract Due to technical complexity, precise and safe fibula shaping for mandibular reconstruction remains a challenge. Robots offer high operational precision, and robotic-assisted osteotomy can meet fibular cutting accuracy requirements. Current research mainly focuses on image-guided serial robotic arms for osteotomy. However, due to insufficient stiffness, joint coupling, and complex, nonunique inverse kinematics, the cutting accuracy of serial robots is limited. To address this, this article proposes a novel hybrid robot system combining a linear delta mechanism for osteotomy and a serial arm for end-effector posture adjustment. The linear delta mechanism provides high stiffness and a unique inverse kinematic solution, overcoming the limitations of serial arms. Based on this configuration, a complete kinematic model is derived, and a robot parameter co-optimization method integrating the hand–eye matrix is proposed. Using an eye-to-hand visual integration approach, this method reduces system cost and improves accuracy. The system’s osteotomy accuracy was verified through model experiments. Results showed that, with the hybrid configuration and calibration optimization, the system achieved a cutting position accuracy of 0.87±0.36 mm and angular accuracy of 1.13±0.51 deg during fibular osteotomy. This study demonstrates the system’s high accuracy and feasibility, providing effective technical support for mandibular reconstruction surgery.