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以徒手弯曲和扭曲真实弹性物体作为输入工具，直接直观地操作CAD和CG中的三维几何模型的被动触觉界面。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触觉输入工具，通过电阻变化测量工具上的三维变形。(2)利用神经网络学习，开发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发展起来的，通过引入一组平行六面体控制体积近似物体形状的简化控制体积，将其扩展到各种形状。(4)在神经网络学习能力有限的情况下，为了测量和计算各种形状的泡沫橡胶输入工具的三维变形，必须最小化和优化泡沫橡胶块所包含的电气端子的数量和配置。通过识别学习过程中重要性较低的神经网络输入层单元，并将其移除，提出了一种最小化和优化神经网络电气终端数量和配置的方法。(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输入工具，将三维CAD和CG的变形、位置/方向控制和参数控制等多种三维几何操作集成在一个工具中。(6)通过对所提出的工具与传统的鼠标键盘界面进行特定任务所需时间和动作次数的定量比较，证实了我们方法的有效性和可行性。

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.