New passivity observers for improved robot force control
New passivity observers for improved robot force control
复制标题
用于改进机器人力控制的新型被动观测器
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
O. Khatib
中科院分区：
文献类型：
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作者：
Mikael Jorda;R. Balachandran;J. Ryu;O. Khatib
本文对先前提出的基于时域无源方法的显式力控制器进行了扩展。在使用经典的无源观测器时，我们遇到了一个能量积累问题：如果系统长时间处于稳定接触状态，能量就会耗散，无源观测器会积累一个很大的值。这导致被动控制器在交互变得不稳定后被延迟触发，因此我们失去了被动控制器的优势。为了处理这种能量积累问题，我们提出了两种新的被动观测器，使我们能够在积累能量的情况下快速检测潜在的不稳定性。我们证明了这些新观察者的理论有效性。此外，我们提出了一种在多自由度机械臂上实现基于被动的显式力控制器的更广义的方法，使用包含传感器灵活性的机器人和环境模型，以及在操作空间框架中的位置/力混合控制器。在KUKA IIWA上对该方法进行了实验测试，验证了改进后的性能。
This paper extends the previously proposed Explicit Force Controller based on Time Domain Passivity Approach. When using the classical passivity observer, we encounter an energy accumulation problem: if the system stays a long time in stable contact, energy is dissipated and the passivity observer builds up a large value. This causes the passivity controller to be triggered late after the interaction becomes unstable, so we lose the advantage of the passivity controller. In order to deal with this energy accumulation issue, we propose two new passivity observers that allow us to quickly detect potential instability despite the accumulated energy. We prove the theoretical validity of these new observers. In addition, we propose a more generalized way of implementing the passivity based explicit force controller on a multi-DoF manipulator, using a model for the robot and environment that includes sensor flexibility, and a hybrid position/force controller in the operational space framework. The proposed method is experimentally tested with KUKA IIWA, and the improved performance is verified.