Development of Space-division Infrared Wireless Communication System for Cooperative Operation and Information Sharing of Multiple Mobile Robots

本文研究了一种用于多移动机器人协同作业的红外无线通信系统。研究了一种既能实现相互通信又能检测其位置的通信系统。伙伴机器人的发射信号可以用作显示其位置的信标信号。每个信标信号的方向在其接收电路中使用PSD（位置敏感装置：光电二极管入射角传感器）检测，并根据其方向通过三角测距计算相互位置。在分布式控制的无线通信网络中，不必要的信号会干扰通信。我们分析了空间干扰因素。当三个机器人组成三角形，其中一个是接收器，另一个是发射器时，它们会造成通信干扰。当将每个光接收机的角度限制在60度以内时，通信机器人形成的三角形的最大内角大于60度。内角最大的机器人成为仲裁者，控制相互间的交流。在仿真中，我们证实了减少干扰的解决方案是使用仲裁者。我们研究了一种结合高速数据传输和精确入射角检测的红外收发器电路。PSD有两个或四个信号输出，入射角由它们的信号强度差计算。发现红外无线通信系统的传输信号为脉冲信号，并利用该信号的特性对降噪进行了研究。我们还检查了NRZI编码的HDLC数据传输，以检测通信链路的中断。在这些研究成果的基础上，我们将研究用于多机器人相互通信的红外无线通信系统。

This is research on an infrared wireless communications system used for cooperative operation of multiple mobile robots. The communication system that can use not only mutual communication but also detect their position was studied. A partner robot's transmitting signal can be used as a beacon signal that shows its position. The direction of each beacon signal is detected using a PSD (Position Sensitive Device: photo-diode incidence angle sensor) in its receiver circuit, and mutual positions are computed by the triangulation ranging based on their directions.In a distributed controlled wireless communication network, unnecessary signals confuse communications. We analyzed the spatial factor of interference. When three robots in which one is a receiver and others are transmitters form a triangle, they cause communication interference. When restricting the angle of each optical receiver to less than 60 degrees, the greatest inside angle of the triangle formed by communicating robots becomes greater than 60 degrees. A robot that has the greatest inside angle becomes an arbiter and it controls mutual communication. In a simulation, we confirmed the solution of reducing interference is using an arbiter.We examined an infrared transceiver circuit that combines high-speed data transmission with accurate incidence angle detection. A PSD has two or four signal outputs, and an incidence angle is calculated from the difference in strength of their signals. We found the property of transmission signal of the infrared wireless communication system is a pulse signal, and we examined noise reduction using the property of the signal. Also we examined the NRZI encoded HDLC data transmission to detect suspension of communication links.We will study the infrared wireless communication system for multi robot mutual communication based on these research results.