pic: Potential Off Season Drive

[cad321]

Originally Posted by Infinity2718

Just a couple of comments.

It looks like the traction wheels are fairly close together, the drive may be tippy when in traction mode. You may be able to package the wheels better with the 4" mecanum wheels from Vex, but I don't have any experience with their performance.

21 fps on mecanum mode may be geared a bit fast for 4 cims, the acceleration may be sluggish.

I'm looking at gearing the mecanums rather high for this chassis just to have some fun with it. For a competition bot I would certainly lower this. That being said I will probably still reduce this a few fps for improved performance.

In terms of the tipping, I hadn't really considered that. Now that I think of that though you are most certainly correct and I will be looking into the best solution for this.

Originally Posted by Greg Woelki

Also about the tippiness in traction mode, I can't tell how much the wheels lift up, but is there any chance of rocking back onto the mecanums in a pushing match?

The mecanum wheels are raised 1/8" above the ground when the traction wheels are down. So I would say that there is a good possibility of the mecanums hitting the ground should the bot start tipping around.

Originally Posted by Electronica1

2. I would recommend pivoting the traction wheel instead of the mecanum wheel. The reasons being that the mecanum wheel always applies sideways force and you will spend more time on the mecanum wheels.

3. Double check your physics for the piston to make sure it can lift a 150ish lbs robot.

1) I would agree about your point on pivoting the traction wheels instead. The reason I have put them this way is due to size constraints due to the larger 6in wheels. However if I were to switch over to the 4in wheels like recommended above, than the size constraints would be no more.

2) I have just re-run my calculations and unfortunately it would appear I have made an error in my initial calculations however should I change my design to incorporate 4in mecanums, the change in dimensions would allow this piston size to work.