近年來，許多學者投入研究醫療虛擬實境，尤其是在手術模擬領域。然而，在手術模擬過程中，觸覺力回饋穩定性對於操作的成功與否至關重要。因此，國際上有許多學者致力於探討觸覺力回饋穩定性以及醫療虛擬實境的相關研究。這些研究皆在提高虛擬實境在醫療手術模擬中的準確性和可靠性。本論文旨在開發一個虛擬醫療手術系統作為應用平台，解決變形模擬和力回饋穩定性最佳化等問題。該系統包含精確的碰撞偵測、即時物理變形、觸覺回饋機制和互動式視覺操作等功能。為了實現更逼真的效果，我們採用了質量彈簧模型作為變形模型，並提出基於距離傳播模式的變形物體形狀呈現方法，使其更接近實際物體的物理變化。為驗證系統的便利性和有效性，我們構建了一個基於觸覺的醫療手術模擬變形系統作為應用實例，並完成系統的整合測試和變形模型的可行性和逼真性的驗證。
此外，我們使用基於能量概念的無源耗散理論(Passivity Theory)來探討虛擬觸覺系統中的力回饋穩定性問題。為了改善觸覺力回饋系統的主要缺點，我們設計了一個阻尼式無源控制器（Impedance-Passivity Controller, IPC），通過模型參數選擇實現系統穩定性和控制增益。另外，我們也設計專屬機械手臂取代單自由度(one-DOF sticking)人為施力方式，以達到實驗的一致性。實驗結果證明，相對於基本無源性系統，所提出的IPC可以實現更快速的穩定控制。然而，IPC需要預先確定觸覺設備和虛擬環境的參數值，因此，我們使用無源耗散理論為基礎，配合模糊控制(Fuzzy Control)的能量預估能力和雙向能量補償優勢，進行IPC控制器優化和穩定性最佳化設計，以改進虛擬物件因負阻尼係數和高彈簧係數而造成的震盪和發散。最後，實驗結果證明模糊無源控制器(Fuzzy-Passivity Controller, FPC)在虛擬實境力回饋穩定響應上具有較佳的控制性能。

In recent years, many scholars have dedicated their efforts to researching medical virtual reality, particularly in the field of surgical simulation. However, the stability of haptic feedback during surgical simulation is crucial to the success of the operation. Therefore, many international scholars have focused on investigating the stability of haptic feedback and its relevance to medical virtual reality research. These studies aim to improve the accuracy and reliability of virtual reality in medical surgical simulation. This study develops a virtual medical surgical system as an application platform to address deformation simulation and force feedback stability issues, including the following functions: precision collision detection, real-time physical deformation, realistic force feedback, and interactive visual operation. The mass-spring model and distance-oriented concept of force propagation are used to describe physical deformation. In conclusion, to validate the system’s convenience and effectiveness, a brain virtual surgical platform is constructed to validate the designed function modules.
In addition, we use energy-based passivity theory to explore force feedback stability in virtual haptic systems. We design an Impedance-Passivity Controller (IPC) to improve some haptic feedback shortcomings and achieve system stability and control gain through model parameter selection. We also design a dedicated robotic arm to replace the one-DOF sticking force method for consistency in the experiment. The results show that IPC can achieve faster stable control than the basic passive system. However, IPC requires predefined parameter values of haptic devices and virtual environments. Therefore, we propose a fuzzy-passivity theorem to study the stability of force feedback of virtual haptic system. The fuzzy-passivity controller can be designed to improve the chief defect, which must spend longer time reaching steadily if consumed energy of the equipment is slow, from the two-port network point of view. Finally, compare with basic passivity, rapidly stable control is achieved under the fuzzy-passivity control.

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