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Unread 18-12-2009, 22:47
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Re: pic: 1557 crab module

Quote:
Originally Posted by lbarger View Post
Agreed, side loading will result in some nasty torque if you use just one support bearing.

Also, you may want to look at how much area you will need for the motor to swing when the assembly pivots. Typically you want swerve/crab to pivot a good 180 degrees to maximize mobility. We stacked our motor above the wheel with a chains (or gears) going down one side.
On top of that, weight is a huge issue. It was stated that they are currently 15lb a module, but may go down to 12. Even 12lb a module is a hefty price for crab. You'll put 50lb on the modules alone, and still have to build your chassis to hold it on. Then you need your electronics and by that time you'll be down to under 45lb just for your manipulator. If you need pneumatics, then you're down to less than 35. It appears your axle for turning the module is offset from your wheel, which means they'll pivot awkwardly. The steel pipe is good if you want to reenact a scene from CLUE, but I don't think it has a place on a robot. Just too much weight.
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