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和一个非自主机器人（也称为自行车）初始位于无限直线的原点。自主机器人能以最大速度1移动。当机器人骑上自行车时，其速度增至v>1，但每次只能有一个机器人骑上自行车，且自行车是非自主的，无法自行移动。出口位于直线上未知位置，距离原点距离为d。机器人具有受限的通信能力：一个机器人是发送者（记为S），可无线发送信息至任意距离，但仅能通过面对面（F2F）方式接收信息；另一个机器人是接收者（记为R），可无线接收信息，但仅能通过F2F方式发送信息。自行车本身不具备通信能力。我们将这两个自主机器人和自行车组成的整体通信模型称为S/R。总体目标是理解非自主机器人在协助两个自主故障机器人疏散中的作用。主要贡献是提出一种新的疏散算法，使得两个机器人在S/R模型下均能从未知出口撤离。我们还分析了以自行车速度v为函数的疏散时间，并给出了该算法在v所有可能取值范围内的竞争比上下界。