人機系統之虛擬運動限制設計：模擬系統與機器人操作之應用

Abstract

現今各種觸覺裝置已廣泛應用在娛樂、教育、訓練、製造、機器人遙控操作、藝術等各領域中，藉由觸覺以增加虛擬物件的真實感或提供力輔助來促進操作感受及提昇工作效能。虛擬運動限制(virtual motion constraint)係由軟體產生，透過力回饋搖桿來限制操作者的運動空間，藉以符合對應的工作要求或提供操作者即時的操作輔助。基於此觀念，本論文提出虛擬運動限制的設計方法，可適用於已知或未定的操作環境，並應用在模擬操控系統及機器手臂操作上。前者，針對已知的模擬工作，我們經由組合虛擬牆來建構運動限制，以兩軸力回饋搖桿發展出一個多功能的虛擬操作系統，可用來模擬多種不同工作的操作裝置，如扳手、排擋器等。我們也提出以像素(pixel)為基礎的方法，不僅便於以圖形編輯軟體來組裝各式虛擬牆，且能在不同牆面間達成力的平滑呈現。實驗結果顯示，該系統能掌握所模擬操作裝置的主要特徵。而後者，關於未定環境的多軸機器手臂操作，我們以運動限制發展一套虛擬工具，如虛擬尺等，根據使用者的需要，提供使用者在位置與方向上的輔助，經由操作六軸力回饋搖桿來操控機器手臂。我們也提出點、線、面等虛擬工具的實現方法，且能在不同工具或方向切換時，仍使輔助力保持平順。為了展現成果，在實驗中本系統執行路徑跟隨以及用扳手鎖螺絲這類需要技巧的操作工作。

Nowadays haptic devices have been applied to many areas, such as entertainment, education, training, manufacturing, telerobotics, art, and so on, to enhance the reality of virtual objects or provide force assistance, and thus to foster manipulative feeling or to improve task performance. Virtual motion constraint is generated via the software, so that the force-reflection joystick, operated by the user, is confined to move within a limited workspace that corresponds to task requirements or provides the user the real-time assistance. Based on this concept, this dissertation proposes methods to design virtual motion constraints, which can be applicable for well-known or uncertain environments, and apply them for simulation systems and robot manipulation. First, for a well-known simulated task, we assembly virtual walls to construct the desired motion constraint and thus develop a multi-functional virtual manipulation system, based on a 2-DOF (degree-of-freedom) force-reflection joystick, to emulate various manipulative devices, e.g., a wrench or gearshift level. We also propose a pixel-based method, which can easily construct these motion constraints by using the graphic editing software and also maintain smooth force rendering between the walls. The experimental results show that this system can capture the main features of various kinds of manipulative devices. Second, for manipulating a multi-DOF robot manipulator in uncertain environments, also based on the concept of virtual motion constraint, we develop a set of virtual tools, e.g., a virtual ruler, which can provide the position or orientation assistance to the user, according to her/his demand on site, to govern the robot effectively by operating a 6-DOF force-reflection joystick. We also implement several kinds of virtual tools, such as a point, line, or plane. Smooth force rendering during the transition between the use of two consecutive tools in guidance are also achieved. For demonstration, the system is employed for the tasks of contour following and screw fastening, which involve delicate and challenging maneuvers.