发表机构
Delft University of Technology; KTH Royal Institute of Technology（代尔夫特理工大学; 皇家理工学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对多机器人拓扑约束运动规划执行慢且次优的问题，提出基于MPC的分布式控制器，利用缠绕数代理辫群规格并解耦为成对问题，结合共识进度估计，在仿真和实验中验证了执行速度与控制努力的提升。
AI 中文摘要
移动机器人的高效分布式协调是多机器人系统面临的主要挑战之一。拓扑约束（通常以拓扑辫群的形式表达）是编码多个移动机器人之间复杂协调模式的常用工具，因为它们提供了机器人时空轨迹之间期望定性关系的紧凑且抽象表示。然而，通过分布式控制器执行以辫群为基础的拓扑约束所编码的联合运动规划具有挑战性，现有方法通常基于一次执行一个辫群生成元，产生缓慢且次优的轨迹。我们提出了一种基于模型预测控制（MPC）的分布式控制器，以高效执行基于辫群的拓扑规格。我们不直接跟踪辫群规格，而是提出使用缠绕数（辫群的拓扑不变量）作为代理。这具有双重好处：将辫群转换为连续函数，可通过成本函数中的适当项轻松由MPC控制器跟踪；以及将全局辫群规格解耦为一组成对规格，可通过仅求解局部MPC问题来分布式跟踪。为了保持全局协调，我们提出了一种基于共识的进度估计方法，允许机器人同步其运动以实现期望规格。我们在仿真和真实世界实验中验证了所提出的方法，展示了所提方法的有效性以及在执行速度和控制努力方面相对于现有方法的改进。
英文摘要
Efficient and distributed coordination of mobile robots is one of the main challenges in multi-robot systems. Topological constraints, often expressed as topological braids, are a popular tool to encode complex coordination patterns between multiple mobile robots, as they offer a compact and abstract representation of the desired qualitative relation between the space-time trajectories of the robots. However, execution of joint motion plans encoded as braid-based topological constraints via distributed controllers is challenging, with existing approaches, generally based on the execution of one braid generator at a time, producing slow and suboptimal trajectories. We propose a distributed controller based on Model Predictive Control (MPC) to efficiently execute braid-based topological specifications. Rather than directly tracking the braid specification, we propose to use winding numbers, which are topological invariants for braids, as a proxy. This has the twofold benefit of converting braids into a continuous function, which can be easily tracked by an MPC controller through an appropriate term in the cost function, and of decoupling the global braid specification into a set of pairwise specifications, which can be tracked distributedly through the solution of only local MPC problems. To maintain global coordination, we propose a consensus-based progress estimation approach, which allows the robots to synchronize their motion toward the desired specification. We validate the proposed approach in simulation and in real-world experiments, where we demonstrate the effectiveness of the proposed approach and the improvement over existing approaches in terms of execution speed and control effort.
Comments19 pages, 13 figures
