Cooperative collision avoidance between robots, or `agents,' in swarm operations remains an open challenge. Assuming a decentralized architecture, each agent is responsible for making its own decisions and choosing its control actions. Most existing approaches rely on a (wireless) communication network between (some of) the agents. In reality, however, communication is brittle. It may be affected by latency, further delays and packet losses, and transmission faults. Moreover, it is subject to adversarial attacks, such as jamming or spoofing. This paper proposes Contingency Model-based Control (CMC), a decentralized cooperative approach that does not rely on communication. Instead, the control algorithm is based on consensual rules that are designed for all agents offline, similar to traffic rules. For CMC, this includes the definition of a contingency trajectory for each robot, and perpendicular bisecting planes as collision avoidance constraints. The setup permits a full guarantee of recursive feasibility and collision avoidance between all swarm members in closed-loop operation. CMC naturally satisfies the plug & play paradigm, i.e., new robots may enter the swarm dynamically. The effectiveness of the CMC regime is demonstrated in two numerical examples, showing that the collision avoidance guarantee is intact and the robot swarm operates smoothly in a constrained environment.

翻译：机器人集群操作中个体（或称“智能体”）间的协同避障仍是一个悬而未决的挑战。在去中心化架构下，每个智能体需自主决策并选择控制动作。现有方法大多依赖（部分）智能体间的（无线）通信网络。然而在实际中，通信具有脆弱性：可能受延迟、附加时延、数据包丢失及传输故障的影响，且易遭受干扰或欺骗等对抗性攻击。本文提出基于应急模型的控制方法——一种不依赖通信的去中心化协同控制框架。该控制算法基于离线为所有智能体设计的共识规则（类似于交通规则），具体包括为每个机器人定义应急轨迹，并以垂直平分平面作为避障约束。该架构能完全保证闭环操作中所有集群成员的递归可行性及相互避障。CMC天然符合即插即用范式，支持新机器人动态加入集群。通过两个数值算例验证了CMC机制的有效性，结果表明避障保证始终成立，且机器人集群在受限环境中能平稳运行。