Robot Dimensions

Hey all, Team 6911 here. As we had a lot of tipping issues last year, we are planning on making our robot very long this year. Currently the chassis is CADed to be 35 x 24. We plan to use a 2 stage lift and a 4 bar linkage to get to level 3 on the rocket. This puts our lift about 3/4 back, and the gearboxes in the front. If someone can give me any input on whether or not 35 is too long I would appreciate it

Personally, I think those dimensions make for a robot thatâ€™s too narrow. 24in is only 2 feet wide. Will your gearboxes touch if you make it that narrow?

Gearboxes do not touch. I do agree that if we get broadsided we may be screwed. Any recommendations on a possible width?

You haveâ€“by my calculationsâ€“12" left in your Frame Perimeter. May I suggest using 8 of those to put your robot to 35 x 28? Thatâ€™s close to one of the older, very workable sizes.

I am fairly certain that the dimensions this year is a 120" perimeter. 35x24 puts us at 118.

Right, my math was wonky.

I would sacrifice some length for width, ORâ€¦

There are no particular rules requiring your robot to be rectangular. Cut some corners off.

Iâ€™m sure that Iâ€™m just being an idiot here, but would cutting the corners off achieve?

I see some teams thinking of going to 28 inches wide. Does that sound more reasonable?

I think so. My team is going 32" by 27.5"

@Alexg were you at maximum weight last year?

@MrRoboSteve we were only about 95 pounds, which now that I think about it probably had something to do with the tipping issue.

Smaller perimeter. Think about a triangle where the legs are a robot with rectangular corners and the hypotenuse is a robot with angled corners. The sum of the 2 legs will always be more than the hypotenuse.

Quite literally this case, cutting corners saves weight.

Geez weâ€™re at 26"x28" I feel super tiny now

And length. This was a fairly common tactic to save frame perimeter length a few years back. The catch is that if any side is <12" the entire side gets bumpers.

So if we could build bumpers that were the shape of a frame with cut corners, we could do that?

So long as you have â‰¥6" of coverage from every corner and full coverage on any corner less than 12", yes.

Absolutely! Matter of fact youâ€™d be required to (definition of Frame Perimeter and bumper attachment rules work together on this). There are a number of ways to accomplish that, ranging from separate segments to each side to forming your one-piece bumpers to follow your frame.

If you need some help on that part, just ask and weâ€™ll be happy to help check your designs.

Thank you very much. I just quickly changed the dimensions on the rails which is why nothing really lines up. So basically as long as the corners are covered with bumper, plus 6 inches on the front, side, and rear rails we are okay?

Not quiteâ€¦ Frame looks fine but bumper rules dictate that you cannot have 8 inches unsupported by frame and must have corners coveredâ€¦ The side will need some kind of standoff for bumper mounts I recommend looking at either team 111 or 217â€™s configurations last year.

Ah. Forgot to mention that I had to take them out for the time being to make the modifications to the dimensions. There are 2x1 standoffs between each wheel that are less than 8 inches apart, I just deleted them for now. My bad