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Thanks, i'll pass the compliment on to one of our teachers that made developing a set of omniwheels his pet project. All parts on that wheel were made by us except for the bearings which i think came out of the wheel chair wheels. There are two sheets of polycarbonate, with wooden rollers on each set, with either sheet individually, it would be like driving on a set of cogs, but the teacher worked out the geometry so that if you look down the axle, the two non-round, components, when offset 45 degrees, form a perfect circle. The wooden rollers are actually pieces of 2x4, cut closely to shape on a table saw, then turned down on this neat little mini-lathe/mill combo thing we have. They are completely unpowered actually, so it doesn't matter how well they grip anywhere, we noticed 3 years ago using swiveling castors on the ramp created some big problems, so we wanted some sort of non-swiveling castors that would work better than skids. We didn't have time for a whole lot of testing, losing a week and a half out of 6 weeks due to snow will cause that to happen, but our other wheels (the powered sets) seemed to have fairly decent grip. I'll work on getting a better picture of those omniwheels loaded soon.
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"The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors, so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe .... In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. "
Carl Sagan
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