Intelligent Interface for 3-D Shape Manipulation Using Various-Shaped Elastic Objects as Input Tools

本研究的目的是提出一种被动式触觉接口，通过弯曲和扭曲真实的弹性物体作为输入工具，直接和直观地操纵CAD和CG中的三维几何模型。结果总结如下。(1)提出了一种由弹性导电泡沫橡胶块制成的被动式触觉输入工具，通过电阻变化来测量工具上的三维变形。(2)采用神经网络学习方法，建立了适用于各种形状泡沫橡胶输入工具的三维变形测量与计算方法。(3)自由变形技术最初是针对平行六面体形状而发展起来的，通过引入一个简化的控制体，该控制体用一组平行六面体控制体来近似物体形状，从而将自由变形技术扩展到各种形状。(4)利用神经网络有限的学习能力测量和计算各种形状的泡沫橡胶输入工具的三维变形，必须使体现到泡沫橡胶块的电端子的数量和分配最小化和优化。通过在学习过程中识别与电气端子相对应的神经网络的输入层单元并去除它们，开发了一种最小化和优化电气端子的数量和分配的方法。(5)提出了一种由泡沫橡胶块、电磁六自由度跟踪器、按钮和滑动体组成的三维几何输入工具，该工具可将变形、位姿控制和参数控制等多种三维几何操作集成到一个工具中，实现三维CAD和CG的一体化。(6)通过定量比较所提出的工具和传统的鼠标-键盘界面所需的时间和数量的行动，为特定的任务，我们的方法的有效性和可能性被证实。

The purpose of this research is to propose a passive haptic interface for manipulating 3-D geometric model in CAD and CG directly and intuitively by bending and twisting real elastic objects as input tools by bare hands. The results are summarized as follows.(1) A passive haptic input tool made of elastic and conductive foam rubber lump to measure 3-D deformation on the tool by electrical resistance change is proposed.(2) 3-D deformation measurement and calculation method applicable to various-shaped foam rubber input tool is developed using neural network learning.(3) Free-form deformation technique, originally developed for parallelepiped shape, is extended to various shape by introducing a simplified control volume which approximates the object shape with a set of parallelepiped control volumes.(4) To measure and calculate 3-D deformation on various shaped foam rubber input tool with a limited learning ability of neural network, the number and allocation of electrical terminals embodied to foam rubber lump must be minimized and optimized. By identifying input layer units, which correspond to electrical terminals, of a neural network with less importance during learning process and removing them, a method of minimizing and optimizing the number and allocation of electrical terminals is developed.(5) An input tool consisting of foam rubber block, electromagnetic six-degree-of-freedom tracker, buttons and slide volumes are proposed to integrate multiple 3-D geometric operations, such as deformation, position/orientation control and parameter controls, for 3-D CAD and CG with a single tool.(6) By quantitatively comparing the proposed tool and conventional mouse-keyboard interface for necessary time and number of actions for specific task, the effectiveness and possibility of our approach are confirmed.