实时的视觉和精细的力觉融合交互算法是实现虚拟手术训练中精准“手感”的关键。为减少存储空间，提高计算效率，精确计算骨铣削过程中的切削力，平衡视觉和力觉融合的交互效果，该文提出了一种基于Tri-dexel模型的视觉与力觉融合交互算法。首先，采用Tri-dexel模型表示骨与医用铣刀，通过布尔运算、快速表面重建及渲染算法实现虚拟骨铣削操作过程中的实时几何变形计算；接着，结合医用铣刀的几何参数，提出基于微元切削力的骨铣削力觉交互模型，利用骨与医用铣刀Tri-Dexel模型之间布尔运算的结果，快速精确求解瞬时未变形切屑厚度；然后，通过槽切实验完成对切削力系数的辨识，并对该力觉模型进行验证分析，实现虚拟骨铣削操作过程中的力觉渲染；最后，基于上述算法搭建骨科虚拟手术训练系统，通过实验对视觉与力觉融合交互算法进行测试与评估。结果表明：力觉模型的预测结果与实验测量结果吻合较好，力的平均相对误差在7%以下；该算法能够同时满足30 Hz的视觉刷新频率以及1 kHz的力觉刷新频率要求；所搭建的骨科虚拟手术训练系统能够为用户提供高沉浸感的虚拟骨铣削操作训练，可有效提高用户的手眼协调能力。

Real-time visual and precise haptic interaction algorithms are critical for achieving accurate “tactile sensation” in virtual surgical training. In order to reduce storage space, improve computational efficiency, accurately calculate cutting forces during bone milling, and balance the visual and haptic interaction effect, this paper proposed a visual and haptic interaction algorithm based on the Tri-dexel model. Firstly, the Tri-dexel model was employed to represent the bone and the surgical milling tool. Real-time geometric deformation during the virtual bone milling was achieved through boolean operations and rapid surface reconstruction algorithms. Secondly, by integrating the geometric parameters of the surgical milling tool, a haptic interaction model based on the micro-element cutting force was proposed. This model utilizes the boolean operation results between the bone and surgical milling tool to quickly and accurately solve the instantaneous undeformed chip thickness. Thirdly, the cutting force coefficients were identified and the haptic interaction model was validated through milling experiments to achieve haptic rendering. Finally, an orthopedic virtual surgical training system was built based on the above-mentioned algorithms, and the interaction algorithm was tested and evaluated experimentally. The results show that the predicted forces align with experimental measurements, with an average force error of less than 7%. The visual and haptic interactive algorithm satisfies a visual refresh rate of 30 Hz and a haptic refresh rate of 1 kHz. The developed orthopedic virtual surgical training system provides users with a highly immersive virtual bone milling training experience that can effectively improve users’ hand-eye coordination.