Non-prehensile manipulation enables fast interactions with objects by circumventing the need to grasp and ungrasp as well as handling objects that cannot be grasped through force closure. Current approaches to non-prehensile manipulation focus on static contacts, avoiding the underactuation that comes with sliding. However, the ability to control sliding contact, essentially removing the no-slip constraint, opens up new possibilities in dynamic manipulation. In this paper, we explore a challenging dynamic non-prehensile manipulation task that requires the consideration of the full spectrum of hybrid contact modes. We leverage recent methods in contact-implicit MPC to handle the multi-modal planning aspect of the task. We demonstrate, with careful consideration of integration between the simple model used for MPC and the low-level tracking controller, how contact-implicit MPC can be adapted to dynamic tasks. Surprisingly, despite the known inaccuracies of frictional rigid contact models, our method is able to react to these inaccuracies while still quickly performing the task. Moreover, we do not use common aids such as reference trajectories or motion primitives, highlighting the generality of our approach. To the best of our knowledge, this is the first application of contact-implicit MPC to a dynamic manipulation task in three dimensions.

翻译：非抓取式操作通过规避抓取与释放的需求，以及处理无法通过力闭合抓取的物体，实现了与物体的快速交互。当前的非抓取式操作方法主要关注静态接触，以避免滑动带来的欠驱动问题。然而，控制滑动接触的能力——本质上移除了无滑动约束——为动态操作开辟了新的可能性。在本文中，我们探索了一项具有挑战性的动态非抓取式操作任务，该任务需要考虑完整的混合接触模式谱。我们利用接触隐式模型预测控制（MPC）的最新方法来处理任务中的多模态规划问题。通过审慎考虑用于MPC的简化模型与底层跟踪控制器之间的集成，我们展示了如何将接触隐式MPC适配于动态任务。令人惊讶的是，尽管摩擦刚性接触模型存在已知的不精确性，我们的方法仍能对这些不精确性做出反应，同时快速执行任务。此外，我们没有使用常见的辅助手段，如参考轨迹或运动基元，这凸显了我们方法的通用性。据我们所知，这是接触隐式MPC在三维动态操作任务中的首次应用。