A passive spherical chain mechanism for hydraulically driven MRI-compatible puncture robot

Purpose This study aims to develop and evaluate a novel magnetic resonance imaging (MRI)-compatible, hydraulically actuated needle insertion robot for minimally invasive stereotactic neurosurgery. The research improves the performance for enhancing precision and reducing human error during delicate and complex MRI-guided surgical manipulations. Design/methodology/approach This research presents a robotic system based on spherical chain mechanisms and communicating vessels, driven by a linear piston and actuator. A double-layer spherical chain mechanism translates linear motion into rotation. An MRI-compatible linear encoder is constructed with grating ruler and optical fiber to ensure precise control. Model predictive control governs trajectory tracking and braking pressure management. The robot’s performance is evaluated by assessing its positional and angular tracking accuracy through real-world experiments. Findings The developed robotic system achieved an average positional accuracy of 1.435 mm and angular accuracies of 0.401°. The system’s precision and repeatability were found to be within the ideal range for stereotactic neurosurgery. Testing confirmed both material and structural compatibility with the MRI environment, demonstrating effective spatial positioning and trajectory planning capabilities. Originality/value This research introduces a novel design for an MRI-compatible needle insertion robot, using hydraulic actuation and a spherical chain mechanism. The demonstrated accuracy and MRI compatibility of the robot offers a valuable contribution to the field of minimally invasive neurosurgery, potentially improving the safety and efficacy of MRI-guided interventions. Future research directions include in vivo testing and further refinement of the control algorithms.