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I just built this little bot this morning! The shape (and code) seems excellent at keeping this bot from "getting stuck" and if I were to add a small sponge to the bottom I could use it to clean my bathroom after in a while! A 5 cell rechargeable AA setup provides more than enough power for flat indoor floors. (Even at relatively slow speeds, the robot runs nicely in a fairly straight line.) The green flanges in back don't drag the ground but function to keep the slightly tail-heavy robot from tipping ...
This is a companion discussion topic for the original entry at https://community.robotshop.com/index.php/robots/show/long-haul