论文标题
使用基于位置的动力学的动力学对可变形绳状对象的可区分机器人操纵
Differentiable Robotic Manipulation of Deformable Rope-like Objects Using Compliant Position-based Dynamics
论文作者
论文摘要
机器人对绳子样物体的操纵是一个有趣的问题,它具有一些关键的应用,例如自主机器人缝合。由于绳索物理的复杂性以及构建快速,准确的可变形材料模型的挑战,因此很难解决和控制绳索。尽管更多数据驱动的方法在寻找学习执行一项任务的控制器方面变得越来越流行,但基于模型的方法仍然有很大的动力,该方法可用于解决各种优化问题。为此,我们介绍了基于位置的动力学(XPBD),以建模类似绳索的对象。使用几何约束,该模型可以代表剪切/拉伸和弯曲/扭曲效果的耦合。至关重要的是,我们的公式是可区分的,可以解决参数估计问题并改善绳索物理与现实生活中的匹配(即,实际到SIM问题)。对于类似绳索的物体的一般性,提出了两个不同的求解器来处理绳索的不同物质刚度的不可扩展和扩展效应。我们使用百特机器人和DA Vinci Research Kit(DVRK)展示了框架对实际到SIM的实验设置的鲁棒性和准确性。我们的工作带来了一种利用现成的梯度的可变形绳状物体的机器人操纵的新途径。
Robot manipulation of rope-like objects is an interesting problem that has some critical applications, such as autonomous robotic suturing. Solving for and controlling rope is difficult due to the complexity of rope physics and the challenge of building fast and accurate models of deformable materials. While more data-driven approaches have become more popular for finding controllers that learn to do a single task, there is still a strong motivation for a model-based method that could be used to solve a large variety of optimization problems. Towards this end, we introduced compliant, position-based dynamics (XPBD) to model rope-like objects. Using geometric constraints, the model can represent the coupling of shear/stretch and bend/twist effects. Of crucial importance is that our formulation is differentiable, which can solve parameter estimation problems and improve the matching of rope physics to real-life scenarios (i.e., the real-to-sim problem). For the generality of rope-like objects, two different solvers are proposed to handle the inextensible and extensible effects of varied material stiffness for the rope. We demonstrate our framework's robustness and accuracy on real-to-sim experimental setups using the Baxter robot and the da Vinci research kit (DVRK). Our work leads to a new path for robotic manipulation of the deformable rope-like object taking advantage of the ready-to-use gradients.