Two autonomous mobile robots and a non-autonomous one, also called bike, are placed at the origin of an infinite line. The autonomous robots can travel with maximum speed $1$. When a robot rides the bike its speed increases to $v>1$, however only exactly one robot at a time can ride the bike and the bike is non-autonomous in that it cannot move on its own. An Exit is placed on the line at an unknown location and at distance $d$ from the origin. The robots have limited communication behavior; one robot is a sender (denoted by S) in that it can send information wirelessly at any distance and receive messages only in F2F (Face-to-Face), while the other robot is a receiver (denoted by R) in that it can receive information wirelessly but can send information only F2F. The bike has no communication capabilities of its own. We refer to the resulting communication model of the ensemble of the two autonomous robots and the bike as S/R. Our general goal is to understand the impact of the non-autonomous robot in assisting the evacuation of the two autonomous faulty robots. Our main contribution is to provide a new evacuation algorithm that enables both robots to evacuate from the unknown Exit in the S/R model. We also analyze the resulting evacuation time as a function of the bike's speed $v$ and give upper and lower bounds on the competitive ratio of the resulting algorithm for the entire range of possible values of $v$.

翻译：两个自主移动机器人与一个非自主移动机器人（亦称为自行车）被置于一条无限长直线的原点处。自主机器人的最大移动速度为 $1$。当机器人骑行自行车时，其速度可提升至 $v>1$，但同一时刻仅允许一个机器人骑行，且自行车本身不具备自主移动能力。出口位于直线上一个未知位置，与原点距离为 $d$。机器人具有受限的通信能力：其中一个机器人作为发送者（记为 S），能够进行任意距离的无线信息发送，但仅支持面对面（F2F）接收信息；另一个机器人作为接收者（记为 R），能够无线接收信息，但仅支持 F2F 发送信息。自行车自身不具备通信能力。我们将由两个自主机器人与自行车构成的整体通信模型称为 S/R 模型。本研究的主要目标是探究非自主机器人在辅助两个存在通信故障的自主机器人撤离过程中的作用。我们的核心贡献是提出了一种新的撤离算法，使得在 S/R 模型下两个机器人均能从未知出口撤离。同时，我们分析了撤离时间随自行车速度 $v$ 变化的函数关系，并针对 $v$ 所有可能的取值范围给出了算法竞争比的上界与下界。