Background: The integration of haptic feedback into robot-assisted minimally invasive surgery (RAMIS) has long been limited by challenges in accurately rendering forces and ensuring system safety. The need for robust, high-fidelity haptic systems is critical for enhancing the precision and reliability of teleoperated surgical tools. Methods: In this study, we present a Nonlinear Impedance Matching Approach (NIMA) designed to improve force rendering by accurately modelling complex tool-tissue interactions. Based on our previously validated Impedance Matching Approach (IMA), our novel NIMA method includes nonlinear dynamics to capture and render tool-tissue forces effectively. Results: NIMA improves force feedback accuracy with a mean absolute error (MAE) of 0.01 (SD 0.02) N, achieving a 95% reduction in MAE compared to IMA. Furthermore, NIMA effectively eliminates haptic "kickback" by ensuring no force is applied by the haptic device to the user's hand when they release the handle, enhancing both patient safety and user comfort. Conclusion: NIMA's ability to account for nonlinearities in tool-tissue interactions provides an improvement in force fidelity, responsiveness, and precision across various surgical conditions. Our findings promote the advancement of haptic feedback systems for robotic surgery, offering a realistic and reliable interface for robot-assisted surgical procedures.

翻译：背景：将触觉反馈集成到机器人辅助微创手术（RAMIS）中，长期以来一直受限于精确渲染力并确保系统安全性的挑战。开发稳健、高保真度的触觉系统对于提高遥操作手术器械的精度和可靠性至关重要。方法：在本研究中，我们提出了一种非线性阻抗匹配方法（NIMA），旨在通过精确建模复杂的器械-组织相互作用来改善力渲染。基于我们先前已验证的阻抗匹配方法（IMA），我们新颖的NIMA方法引入了非线性动力学，以有效捕获并渲染器械-组织力。结果：NIMA将力反馈精度提高了平均绝对误差（MAE）为0.01（标准差0.02）N，与IMA相比，MAE降低了95%。此外，NIMA通过确保当用户松开手柄时触觉设备不会向用户的手施加任何力，有效消除了触觉"回弹"，从而提高了患者安全性和用户舒适度。结论：NIMA能够考虑器械-组织相互作用中的非线性因素，从而在各种手术条件下提高了力保真度、响应性和精度。我们的研究结果推动了机器人手术触觉反馈系统的进步，为机器人辅助手术程序提供了一个真实且可靠的交互界面。