3-D Interface for Dynamic Geometric Operation Using Plastic Object as Input Tool

在本研究中，我们提出了一种像黏土一样进行塑化处理的输入工具，作为一个实时的三维形态操作界面。首先，研究了改性(两点距离的变化)是电可测量的塑料材料，并选择了由蜡、机油、碳酸钙、肥皂和甘油组成的油性粘土。根据对所选导电粘土特性的基本实验结果，设计并制造了具有8个端子到导电粘土立方体的8个顶点的输入装置。设计了补偿导电粘土中每个测量值的有限精度的方法如下：-一般措施，例如通过取时间测量值的两个或多个平均值来平滑噪声，以及死区的设置，其将测量值削减到指定量以下。-在端子周围准备盖子以减少由手动操作引起的端子和粘土之间的接触状态变化(压力)的影响。-通过假设粘土体积恒定来补偿整个修改计算结果。-使用测量值变化率而不是值本身来补偿材料的不均匀性和端子特性。-使用在本地两个端子之间测量的阻值来补偿端子和粘土之间的局部接触状况。上述补偿方法被实施到输入工具。经证实，当用户弯曲、按压和扭曲粘土工具时，其三维变形被电测并应用于计算机显示器上的虚拟模型。此外，作为输入工具的导电粘土的精度和稳定性有限的问题，它最初不是设计或制造成用作传感器的。

In this research, we propose an input tool which carries out plastic modification like clay as a real time three-dimensional form operation interface. First, plastic material with which modification (change of the distance for two points) is electrically measurable is investigated and an oil clay consisting of wax, machine oil, calcium carbonate, soap, and glycerin is selected. Based on the result of basic experiments about the characteristic of the selected conductive clay, the input device having eight terminals to the eight vertices of a conductive clay cube is designed and manufactured.The methods for compensating limited accuracy of each measurement value in the conductive clay are devised as follows.-General measures, such as smoothing noises by taking two or more averages of the measurement values for time, and a setup of dead zone which cuts the measurement value below a specified amount.-Preparation of a cover around a terminal to reduce an influence of a contact state change (pressure) between a terminal and clay caused by hand operation.-Compensation of the whole modification calculation result by assuming that the clay volume is constant.-Using the rate of measurement value change, instead of the value itself to compensate the inhomogeneity of the material and the terminal characteristic.-Using the measured resistance value between local two terminals to compensate local contact condition between the terminal and the clay.The above compensation methods are implemented to the input tool. It is confirmed that when a user bends, presses and twists the clay tool, its 3-D deformation is electrically measured and applied to a virtual model on a computer display. Also, the problem of limited accuracy and stability of the conductive clay as an input tool which it not originally designed or manufactured to be used as a sensor.