论文标题
具有安全性和稳定性特性的非线性动力学系统的强大学习
Robust Learning of Nonlinear Dynamical Systems with Safety and Stability Properties
论文作者
论文摘要
本文提出了一种可靠的参数学习方法,用于从数据中识别非线性动力学系统,同时在从演示方法(LFD)方法中学习的情况下满足安全性和稳定性约束。极限学习机器(ELM)用于近似系统模型,在存在模型不确定性和外部干扰的情况下,使用零屏障和基于Lyapunov的稳定性分析获得的安全性和稳定性约束。开发了一个约束二次程序(QP),该程序说明ELM函数重建误差,以估计ELM参数。此外,还提出了鲁棒性的引理,这证明了学习的系统模型可以在存在干扰的情况下确保安全性和稳定性。该方法在模拟中进行了测试。将该方法的轨迹重建精度与使用扫描误差区域(SEA)度量的最新LFD方法进行了比较。通过进行蒙特卡洛测试来测试学习模型的鲁棒性。所提出的方法是在Baxter机器人上实现的,用于将机器人限制在椭圆形安全区域的拾取任务中。
The paper presents a robust parameter learning methodology for identification of nonlinear dynamical system from data while satisfying safety and stability constraints in the context of learning from demonstration (LfD) methods. Extreme Learning Machines (ELM) is used to approximate the system model, whose parameters are learned subject to the safety and stability constraints obtained using zeroing barrier and Lyapunov-based stability analysis in the presence of model uncertainties and external disturbances. A constrained Quadratic Program (QP) is developed, which accounts for the ELM function reconstruction error, to estimate the ELM parameters. Furthermore, a robustness lemma is presented, which proves that the learned system model guarantees safety and stability in the presence of disturbances. The method is tested in simulations. Trajectory reconstruction accuracy of the method is compared against state-of-the-art LfD methods using swept error area (SEA) metric. Robustness of the learned model is tested by conducting Monte Carlo tests. The proposed method is implemented on a Baxter robot for a pick-and-place task where the robot is constrained to an ellipsoidal safety region.