Virtual Fixture Control for Compliant Human-Machine Interfaces

— In human-machine collaborative systems, robot joint compliance and human-input dynamics lead to involuntary tool motion into undesired regions. To correct this, a set of methods, called Dynamically-Defined Virtual Fixtures, was previously proposed to create a movable virtual fixture that stops the user at a safe distance outside the forbidden region. In this work, a new method, called the Force-Based Method, was added. A vision system was introduced for real-time tool tracking. Additionally, we implemented a closed-loop controller with the virtual fixtures that allows the user to reach, but not enter, the forbidden region. Two user experiments were conducted on a 1-DOF testbed to evaluate the virtual fixture methods. The first experiment showed the effectiveness of the virtual fixtures in preventing the penetration. However, the absence of haptic feedback in the closed-loop implementation resulted in boundary penetration. In the second experiment, visual feedback was used to ...

• Type: Conference
• Year: 2007
• Where: ICRA
• Authors: Panadda Marayong, Hye Sun Na, Allison M. Okamura
• Keywords: Forbidden Region, Haptic Feedback, ICRA 2007, Robotics, Virtual fixtures