pic: 1557 crab module

[gorrilla]

Originally Posted by Thermal

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.

sorry about the late reply, I had to change my email...

again, there is only one module.

yes i know its heavy, its just a prototype. if we actually decide to make a full crab drive for competition, the pipes will more than likely be alluminum.

And the pipe is not offset, its directly over the center of the wheel. so our center of rotation is directly over the wheel.

we decided to set them up to rotate 180. and measured everything on our old frame so they stay within the boundries and take up the least amount of space.

as for the side loading, we knew this could be a problem,
for the prototype we went without it to save time, but if we make the full system, the other end will be supported. we will probably weld the entire "box" that we have now together with some extention to support the shaft.

do you think it could work without it? or is the force so much that it is a neccessity?