Control Barrier Functions for Mechanical Systems: Theory and Application to Robotic Grasping
Control Barrier Functions for Mechanical Systems: Theory and Application to Robotic Grasping
复制标题
机械系统的控制屏障功能：机器人抓取的理论与应用
DOI：
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发表时间：
2019
影响因子：
4.8
通讯作者：
Peter Choong
中科院分区：
文献类型：
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作者：
Wenceslao Shaw Cortez;D. Oetomo;C. Manzie;Peter Choong
控制障碍函数已被证明是一个有用的方法，以确保约束满足广泛的一类控制器。然而，现有的结果大多局限于连续时间系统。机械系统，包括机器人，通常是二阶系统，其中控制发生在力/扭矩水平。这些系统具有致动器、速度和位置约束（即，相对程度2），这对于安全和/或任务执行至关重要。此外，机械系统通常作为采样数据系统进行数字控制。本文的贡献是双重的。第一个贡献是新的，强大的控制障碍功能，确保约束满意的采样数据系统中存在的模型不确定性，并允许满意的执行器约束的发展。第二个贡献是所提出的方法的应用程序的机器人抓取的挑战性问题，其中机器人手必须确保一个对象保持在把握，同时操纵它所需的参考轨迹。提出了一种满足抓取约束的控制器，该控制器可以接纳文献中现有的标称操纵控制器，同时确保无滑移、无过度伸展（例如，奇异的配置），并且没有指尖的滚动。仿真和实验结果验证了所提出的控制机器人手的应用。
Control barrier functions have been demonstrated to be a useful method of ensuring constraint satisfaction for a wide class of controllers. However, the existing results are mostly restricted to continuous-time systems. Mechanical systems, including robots, are typically second-order systems in which the control occurs at the force/torque level. These systems have actuator, velocity, and position constraints (i.e., relative degree two) that are vital for safety and/or task execution. Additionally, mechanical systems are typically controlled digitally as sampled-data systems. The contribution of this article is twofold. The first contribution is the development of novel, robust control barrier functions that ensure constraint satisfaction for sampled-data systems in the presence of model uncertainty and allows for satisfaction of actuator constraints. The second contribution is the application of the proposed method to the challenging problem of robotic grasping in which a robotic hand must ensure that an object remains inside the grasp while manipulating it to the desired reference trajectory. A grasp constraint satisfying controller is proposed that can admit the existing nominal manipulation controllers from the literature while simultaneously ensuring no slip, no overextension (e.g., singular configurations), and no rolling off of the fingertips. Simulation and experimental results validate the proposed control for the robotic hand application.