Thread: pic: 217 Gen 2 Crab Module Section view
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Unread 28-04-2003, 18:26
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Paul Copioli Paul Copioli is offline
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How it works
M. Krass,

Everything you said is correct. The only reason we had 2 sprockets on the crab module was for spacing. One crab module only had the lower sprocket. The Van door motor did the steering of both steering wheels. The "torque steer" you describe is real, but we only used 4" wheels and it was very minimal. We did not see any reverse motion when steering and not driving. Last year we did not use the sprockets near the wheel and used two wheels with the drive gears in the middle. The torque steer was pretty noticeable, but it didn't really hinder us all that much.

One note on your observation about the reasons for relocating the transmission using bevel gears. The main reasons we do it is to save space and to be able to shift rather easily. A shifting transmission on turning wheels makes them a pretty large thing to package.