The e-puck robot has been developed as an open tool. An article illustrating the concept and design is:

Mondada, F., Bonani, M., Raemy, X., Pugh, J., Cianci, C., Klaptocz, A., Magnenat, S., Zufferey, J.-C., Floreano, D. and Martinoli, A. (2009) The e-puck, a Robot Designed for Education in Engineering. Proceedings of the 9th Conference on Autonomous Robot Systems and Competitions, 1(1) pp. 59-65. 

To exploit in the best way this tool, it's important to know it well. This section include general information about the hardware of the robot and its specifications. Full specifications (schematics and more) can be found in the download section (top menu).

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