Evaluation of subsumption architecture controller by wireless multiple mobile robots system

Until now, we have proposed a multiple mobile robots system based on wireless communication using simple hardware and software. The controller of the system is developed based on a subsumption architecture to realize a swarm intelligence. The subsumption architecture is constructed in a supervisory PC server. The subsumption architecture generates eight kinds of simple commands. The server transmits a communication packet including the command to each mobile robot by wireless communication. Each mobile robot moves based on the received command while transmitting a response packet including six Position Sensitive Detector (PSD) sensors' information to the server. The sensors' information is used as the inputs for three agents in the subsumption architecture. In this paper, to realize a more biological behavior, a bend sensor is added in the robot through a compact A/D converter and the corresponding agent is newly designed in the controller of the server. It is expected that not only the added agent works as emergency escape function to defend the robot itself but also other analogue sensors can be easily equipped with. Also, to examine the actual delay of the system in using serial communication and wireless communication, dynamic sampling period is experimentally measured by using multi media timer with 2 ms resolution on Windows system. The dynamic sampling period is the communication time required between the PC server and the robot. In addition, the success rate of communication, which is defined as the ratio of reception times to transmission times, is evaluated. The measured results are shown and discussed.