基于力反馈技术的三维模型表面绘制研究

Research on 3D model surface rendering based on force feedback technology

将力反馈技术引入虚拟绘制过程中,提出一种基于力反馈技术的三维模型表面绘制方法。首先分析毛笔在三维绘制过程中的受力和变形,采用弹簧—振子模型建立三维毛笔模型;然后由毛笔碰撞变形后的最小包围球找出碰撞相关点,计算碰撞相关点的平均法矢确定投影平面,通过计算毛笔的变形得出在投影平面上的笔触,将该笔触投影到三维模型表面,同时控制毛笔的受力和运笔路径,叠加笔触获得具有特定书法效果的三维笔道;最后介绍了仿真系统,使用Phantom Desktop力反馈设备在该系统中实现了三维模型表面的绘制。仿真结果表明,该方法再现了三维模型表面绘制的力觉控制过程,增强了绘制过程中的真实感。

This paper proposed a novel method of 3D model surface rending by applying force feedback technology to virtual painting processes. Firstly, it analyzed the relationship between force and the brush deformation, and applied the spring-mass model to construct the 3D brush model. Then, it found out the collision related points by the most enclosing ball of the deformed brush, and calculated the average normal vector of the collision point to determine the projection plane. According to the deformation of the 3D brush, it calculated the footprint of the brush on the plane and obtained the 3D brush footprint by projecting the 2D brush footprint onto the 3D object surface in real time. At the same time, it obtained the specific complete calligraphy effect 3D brush stroke by superimposing 3D brush footprints along the painting direction and controlling the stress of the brush. Finally, this paper briefly discussed the simulation structure and established the virtual 3D painting system based on Phantiom Desktop device. The proposed method implementes the 3D painting in real time with a Phantom Desktop haptic device, which can effectively enhance reality to users.