Development of Visual Haptic Display Using Flexible Sheet

开发了一种使用柔性板材呈现虚拟软对象的视觉触觉显示系统。1.橡胶等柔性板材拉伸时变硬，松开时变软。因此，如果改变施加到纸张上的偏压张力，用户在直接触摸纸张时可以感受到不同的顺应性。我们研制了一种触觉显示器，它由两个机械手和一个半透明的柔性板组成，柔性板的两侧固定在机械手上。我们实现了一种通过使用操纵器拉动纸张来改变纸张顺应性的控制方法。然后测量了板材的力-位移曲线。结果表明，该系统可以通过改变偏置张力来产生可变的板材柔度。我们还开发了一种控制方法，用于移动薄片的机械手，使其可以是虚拟对象在用户手指接触的点处的切平面。我们进行了一个主动触摸的实验：抚摸vi…作为一种直观的显示，我们提出了一种将变形的虚拟软体的三维CG图像直接从背面投影到薄板上的方法。首先，通过立体摄像机测量用户手指的三维位置，并获得虚拟对象被推入多深。其次，用有限元方法计算了物体的变形。第三，将变形对象的三维CG图像从其背面直接投影到薄板上。然后，用户通过立体眼镜看到薄片上的虚拟对象。当用户使用上述触觉显示器触摸虚拟对象时，投射在纸张上的CG图像因纸张的移动和按下纸张而变形。因此，我们开发了一种校正这种CG图像失真的方法。通过将上述触觉显示和视觉显示相结合，用户可以看到虚拟软体的三维CG图像，并直接进行触摸。他们可以通过推动感受到物体的顺应性，通过主动触摸感受到物体的形状。较少

A visual haptic display system using flexible sheet for presenting virtual soft objects is developed.1.A flexible sheet such as rubber becomes hard when it is tensioned; it becomes soft when loosened. Hence, if the bias tension applied to the sheet is changed, users can feel different compliance when they touch the sheet directly. We developed a haptic display which consists of two manipulators and one translucent flexible sheet; both sides of the sheet are fixed to the manipulators. We implemented a control method of varying the sheet compliance by pulling the sheet using the manipulators. Then we measured the force-displacement curve of the sheet. As a result we showed that this system can generate variable sheet compliance by changing the bias tension. We also developed a control method for the manipulators of moving the sheet so that it may be a tangential plane of a virtual object at the point which a user's finger touches. We performed an experiment of active touch: stroking a vi … More rtual cylinder with a finger.2.As a visual display we proposed a method of projecting three dimensional CG image of a deformed virtual soft object directly on the sheet from its backside. First the three-dimensional position of a user's finger is measured by stereo cameras and obtained how deep the virtual object is pushed. Second the deformation of the object is calculated by finite element method. Third the three dimensional CG image of the deformed object is projected directly on the sheet from its backside. Then the user sees the virtual object on the sheet through stereoscopic glasses. When the user touches the virtual object using the above-mentioned haptic display, the CG image projected on the sheet is distorted by the movement of the sheet and the depression of the pushed sheet. Thus we developed a method of correcting this CG image distortion. We evaluated the accuracy of the corrected image seen from the user's viewpoint and showed the effectiveness of this image correction.3.By integrating the above-mentioned haptic display and visual display, the users can see the three-dimensional CG image of a virtual soft object and touch it directly. They can feel the compliance of the object by pushing and the shape of the object by active touch. Less