Haptic-Enhanced Virtual Reality Simulator for Robot-Assisted Femur Fracture Surgery

In this paper, we develop a virtual reality (VR) simulator for the Robossis robot-assisted femur fracture surgery. Due to the steep learning curve for such procedures, a VR simulator is essential for training surgeon(s) and staff. The Robossis Surgical Simulator (RSS) is designed to immerse user(s) in a realistic surgery setting using the Robossis system as completed in a previous real-world cadaveric procedure. The RSS is designed to interface the Sigma-7 Haptic Controller with the Robossis Surgical Robot (RSR) and the Meta Quest VR headset. Results show that the RSR follows user commands in 6 DOF and prevents the overlapping of bone segments. This development demonstrates a promising avenue for future implementation of the Robossis system.Comment: This paper is submitted to the IEEE Haptic Symposium 202

Design and Experimental Evaluation of a Haptic Robot-Assisted System for Femur Fracture Surgery

In the face of challenges encountered during femur fracture surgery, such as the high rates of malalignment and X-ray exposure to operating personnel, robot-assisted surgery has emerged as an alternative to conventional state-of-the-art surgical methods. This paper introduces the development of Robossis, a haptic system for robot-assisted femur fracture surgery. Robossis comprises a 7-DOF haptic controller and a 6-DOF surgical robot. A unilateral control architecture is developed to address the kinematic mismatch and the motion transfer between the haptic controller and the Robossis surgical robot. A real-time motion control pipeline is designed to address the motion transfer and evaluated through experimental testing. The analysis illustrates that the Robossis surgical robot can adhere to the desired trajectory from the haptic controller with an average translational error of 0.32 mm and a rotational error of 0.07 deg. Additionally, a haptic rendering pipeline is developed to resolve the kinematic mismatch by constraining the haptic controller (user hand) movement within the permissible joint limits of the Robossis surgical robot. Lastly, in a cadaveric lab test, the Robossis system assisted surgeons during a mock femur fracture surgery. The result shows that Robossis can provide an intuitive solution for surgeons to perform femur fracture surgery.Comment: This paper is to be submitted to an IEEE journa

Sunram 5: A Magnetic Resonance-Safe Robotic System for Breast Biopsy, Driven by Pneumatic Stepper Motors

Sunram 5 is the fifth generation MR safe robotic system for breast biopsy. It has five degrees of freedom and is driven by six linear and curved pneumatic stepper motors plus three singular cylinders, all constructed by rapid prototyping techniques. A stepper motor consists of two or three pneumatic cylinders that act on a straight or curved toothed rack. The design, production and evaluation of both single pneumatic cylinders and various types stepper motors are described in detail in this chapter, including design aspects such as the optimal geometries of cylinders, pistons, seals and teeth. Control strategies are also discussed such as how multiple motors inside the Sunram 5 can be controlled to achieve both high speed and high accuracy, despite the relatively low stepping frequencies associated with long pneumatic lines between controller and motor in an MRI setting. This way, Sunram 5 provides fast and precise needle insertions under near-realtime MRI guidance, resulting in improved accuracy and efficiency in MRI-guided breast biopsy procedures