pic: 6-sided tank drive
 

Re: pic: 6-sided tank drive
 

Not sure if the 1*1 stuff supporting the bumpers is vexpro versachassis stuff, but if so I'd double layer it or use thicker material. That stuff is really thin for a bumper frame.

Re: pic: 6-sided tank drive
 

If it's welded together with 1/8" walls, it shouldn't be a problem

Re: pic: 6-sided tank drive
 

right; the 1*1 vexpro stock has much thinner walls. I'm not sure which it is.

Re: pic: 6-sided tank drive
 

If I may ask, why are your angles "149.07 degrees" and "105.46"? You will never ever need that kind of precision in a FRC situation, especially on a frame which will be bashed and smashed into every 6 seconds anyways.*

Even with a chopsaw/bandsaw/mill/cnc mill/whatever, it is certainly a better real world design if you round those off to some amount. How critically important is it that you are exactly perfect? In your robot's frame, just about never.

Also, just a recommendation, While it is less pretty, using 1/32" (or preferably 1/16" or 1/8") increments instead of decimals is much less of a hassle for whoever will measure the parts, and just a couple clicks in CAD

Not trying to be a wet blanket on this design, it certainly is cool, but it would be beneficial for every party involved if you simply rounded to the most convenient dimensions, where there will be an immeasurable difference in performance, but a significant improvement in both engineering design quality, and manufacturing


*after all, the entire point of a 6 sided drive like this is for the very purpose of escaping trapping t-bones"

Re: pic: 6-sided tank drive
 

The weird angles are the result of the not-weird side lengths. The tolerance should be pretty high.
Oh, and it's welded 1/8" aluminum tubing

Re: pic: 6-sided tank drive
 

Does it meet the 110" rule?

Re: pic: 6-sided tank drive
 

Question for you, how exactly is this useful? I love the design, it looks pretty fancy, but in the long run it will amount to more work and not be worth it if doesn't have any specific benefits compared to a 4-sided tank drive.

Re: pic: 6-sided tank drive
 

This design is helpful for avoiding t-bone pins and defense in general. Also hexagons have a greater area to perimeter ratio.

Re: pic: 6-sided tank drive
 

If you are going to forgo the square, a hexagon is really the best option for a traditional tank drive. For things like holonomic and 3 wheeled swerve, other n-gons may be appropriate.

Circles are mathematically the optimal perimeter-to-area figures, but would be difficult to make, and a nightmare to put bumpers on.

Re: pic: 6-sided tank drive
 

You can more efficiently optimize the use of the perimeter sizing by moving the front/rear wheels to inside the frame, and making the center wheel wider.

Re: pic: 6-sided tank drive
 

Ah, good point, although T-Bone pins are rather rare. However, would the bot be able to play an effective defense? For example, if the objective was to T-Bone a bot of the other alliance, it would require rather exact precision as to hit the bot right in the middle of their side.

Re: pic: 6-sided tank drive
 

I saw them happen quite a bit this season. Robots waiting for the ball from a human player after a truss were prime candidates for being bulldozed back to the inbound station

Re: pic: 6-sided tank drive
 

Not necessarily, if they are hit square to an angled face, at least the drivetrain is not perpindular to the t-boning robot.

T-bones happen a LOT at the high level of play in certain games.

Re: pic: 6-sided tank drive
 

Fair enough. It is true that they happened this season a lot, but this was due to the lack of mobility some robots had as they waited for the ball from the human player. On a good driver, t-bones tend not to be effective as a good driver will stay in motion as much as possible.