NRI: Dexterous Manipulation Attained Using Task-Specific Admittance Realized with Variable Impedance Actuation

该项目为设计下一代机器人和智能机器人设备建立了一个健全的工程框架，这些机器人和智能机器人设备可用于快速可靠地执行困难的操作任务。该框架既适用于已安装在制造工厂的传统机器人，也适用于未来将使人机协作更加安全的“软机器人”。重点是约束操作问题，如装配和修理任务，其中许多是枯燥、困难和危险的。研究结果将使机器人更有效地应用于服务、医疗保健、太空探索和制造业等广泛领域。该项目提供了一种同时控制机器人位置和弹性行为的方法，使用由具有可控刚度的致动器驱动的运动学冗余臂。将证明，适当的机器人路径规划和导纳规划的设计将确保操作任务施加的约束得到适应，并且尽管存在不确定性（例如，门被打开，组装正确完成），也能可靠地满足高级任务目标。本研究计划的四个主要成果是：1)选择最优操作方案（确定最优运动和导纳方案）的一般程序，使用数值程序确保指定的操作任务在不确定的情况下快速、适当和可靠地进行；2)实现指定导纳方案的程序，涉及在每个关节使用具有可变阻抗驱动的冗余串联机械手（具有可控刚度的串联弹性驱动器）；3)利用可变阻抗驱动冗余串行机械手，验证了机器人在受限操作任务中的灵巧性，验证了操作方案的选择方法和整体操作方法的有效性；4)建立了具有最优操作方案的受限通用任务类别库。

This project establishes a sound engineering framework for designing next-generation robots and intelligent robotic devices that can be used to perform difficult manipulation tasks quickly and reliably. The framework is useful both for traditional robots already installed in manufacturing plants and future "soft robots" that will make human-robot collaboration safe. The focus is on constrained manipulation problems such as assembly and repair tasks, many of which are dull, difficult, and dangerous. The results will allow robots to be more effectively used in a wide range of domains such as service, healthcare, space exploration, and manufacturing.The project yields a means to simultaneously control both a robot's position and its elastic behavior using kinematically redundant arms driven by actuators with controllable stiffness. It will be demonstrated that proper design of the robot path plan and admittance plan will ensure that constraints imposed by manipulation tasks are accommodated and high-level task objectives are reliably satisfied despite uncertainies (e.g., the door is opened, the assembly is completed properly). The four planned major outcomes of this research program are: 1) general procedures for selecting the optimal manipulation plan (identifying the optimal motion and admittance plans) using numerical procedures to ensure that the specified manipulation task progresses quickly, appropriately, and reliably despite uncertainties, 2) procedures for realizing a specified admittance plan involving the use of a redundant serial manipulator with variable impedance actuation (a series elastic actuator with controllable stiffness) at each joint, 3) a demonstration of improved robot dexterity in constrained manipulation tasks using redundant serial manipulators with variable impedance actuation to verify the manipulation plan selection methods and validate the overall manipulation approach, and 4) a library of constrained generic task categories with associated optimal manipulation plans.