pic: Octocanum Module

[Chak]

Originally Posted by GeeTwo

I would also add some springs to lift the mecanum wheel off the floor when not in use to reduce drag and wear; they just need to be strong enough to lift the mecanum wheel, sprocket, bracket and chain. You should be able to anchor them to the top of the translucent bracket in the render by adding a couple of holes on either side of the cylinder.

Or you can use the piston (assuming it's a double piston) to lift the mecanum off the ground. Then you would need to actually attach the piston to the module, maybe using these rod ends from mcmasters.

I notice that you have an extra bearing on the end of the traction wheel shaft. What is it for?

For the bracket that holds the piston: one side is attached to the frame, what's the other side attached to?

[Ari423]

Originally Posted by Chak

Or you can use the piston (assuming it's a double piston) to lift the mecanum off the ground. Then you would need to actually attach the piston to the module, maybe using these rod ends from mcmasters.

I notice that you have an extra bearing on the end of the traction wheel shaft. What is it for?

For the bracket that holds the piston: one side is attached to the frame, what's the other side attached to?

I looked into attaching the piston to the module, but it requires two joints (one at the piston end and one at the cylinder end). That's a little more complexity than I was looking for, and it would make the mounting plate for the piston that much higher. I will add in a spring return for the module in version 2 like GeeTwo suggested.

Not pictured in the render is another piece of VersaFrame stock. This is the outside of the robot where the bumpers will be mounted. You can see how the module fits into the second piece more clearly in the 3D model on GrabCAD.

[GeeTwo]

Originally Posted by Chak

I notice that you have an extra bearing on the end of the traction wheel shaft. What is it for?

For the bracket that holds the piston: one side is attached to the frame, what's the other side attached to?

The answer to both questions is in the OP - there's another piece of VF stock not shown in the render which answers both.

[philso]

Originally Posted by Chak

I notice that you have an extra bearing on the end of the traction wheel shaft. What is it for?

For the bracket that holds the piston: one side is attached to the frame, what's the other side attached to?

Is there a frame element in the foreground, running parallel to the 2 x 1 tube that you have hidden?

It looks like you have only two thin standoffs tying the two plates of the octanum module together. They may "twist" relative to one another as forces are applied to the module. The plates look pretty thin which may make this worse. If they are really thin, the pocketing will not save you a worthwhile amount of weight. If you are going to pocket the module plates, radius the corners (with larger radii near the standoffs). In 2014, we used 1/8" plate. I seem to recall that they did bend a bit after a number of hard hits from the side so you may want to make sure they don't bind on the frame if this happens.

You may also want to consider how the modules will be assembled and how you would service them, say to change a wheel. Do they have to be assembled in the frame? Our 2014 modules took over an hour to assemble, each. It may be best to investigate how 148 designed theirs. They could assemble theirs outside the robot and swap one complete module for another in just a few minutes by removing one or two bolts. You and your team mates would be much happier working on a design more like 148's than ours.