The CiberMouse@DCOSS2008 competition is based on the CiberMouse Simulation Environment. This simulator has been used for a well-known competition in Portugal, the Ciber-Rato Contest, which is run annually since 2001 in the University of Aveiro - DETI / IEETA, as well as in the last two editions of the Student Design Competition of the RTSS Symposium (CiberMouse@RTSS2007 CiberMouse@RTSS2006 ).
In turn the Ciber-Rato Contest is part of an older and larger event, the Micro-Rato Contest, in which small real robots compete, with similar rules. This was created in 1995, vaguely inspired on the IEEE Micro-Mouse Competitions of the 80s.
Technically speaking, the task of the robotic team is finding a target area, signaled by an IR light emitting beacon, and bring the whole team mates there. The final score depends on the number of robots that get to the target area, on the time of the last robot that get into the area and on possible penalties due mainly to collisions with walls and other robots. During the competition the robotic agents form a distributed environment, where simulator and robots may be executed in separate computers connected to an isolated IP LAN. Communication among the robotic agents is carried out exclusively via an emulated ad-hoc wireless communication protocol with realistic parameters (limited bandwidth, limited range and a random non-zero latency and error probability). The simulator and all robots form a distributed system but, for practical purposes, may also be executed in a single computer. Nevertheless, communication is only allowed via the provided API.
A graphical front-end shows the maze, the movement of the robots inside the maze, their scores and provides a control panel to manage the competition.
The maze is a rectangular area, delimited with walls and populated with obstacles. Start point, target area, walls and obstacles are unknown to the robots at the beginning. Moreover, there are obstacles higher and lower than the target beacon.
The virtual body of the robots has a cylindrical shape and is equipped with sensors and actuators. The sensory system is composed of obstacle sensors, target beacon sensor, compass, and a bumper. The main actuators are two diametrically opposed motors controlling two independent wheels in a differential drive fashion.
This time, special features were added to the simulation
environment to motivate using sensor network design methods. In particular,
communication has been added to the simulated model, a noisy GPS is
available to the robots during competition and selective delays have been added in the access to the sensory information as
well as limitations to the amount of sensory information that can be
obtained with each query. These will require a judicious control of speed
and selection of sensor queries in order to avoid bumping against obstacles
and other robots which cause penalties.
