375 LBS??
 

Team Driven has a driving chassis. And it is super powerful. Check out the video.

Re: 375 LBS??
 

Wow, that chassis looks awesome. Looks very small and thin. Are we allowed to know the dimensions of it :yikes:

Re: 375 LBS??
 

We used the golden ratio to determine our length and width. Still keeping a perimeter of about 110".

Re: 375 LBS??
 

What is the ratio?

*edit* Posters below answered it.

Re: 375 LBS??
 

Well if they are referring to phi I think it would be more like 34x21

Re: 375 LBS??
 

If I'm not mistaken, the golden ratio is 1.618:1

Edit: Got beat to it, 34/21 is 1.619 with sounds just about perfect.

Re: 375 LBS??
 

Not to take anything away from your great looking drivetrain, but pushing 375 pounds of mass sitting in a chair is not the equivalent of having 375 pounds of pushing force. The coefficient of friction between the chair legs and carpet is certainly less than 1.0, so the actual pushing force would be less than that.

That said, beautiful drivetrain.

Re: 375 LBS??
 

True, but a robot on wheels (while unpowered of course and parallel to our own wheels) should theoretically have a lower coefficient of friction than the chair? Please correct me if I'm wrong.

Re: 375 LBS??
 

Not necessarily. You appear to be using the AM HiGrip Wheel (if I'm not mistaken), and assuming your carpet is standard FRC carpet, the CoF is listed as 1.067. I'd guarantee that roller chair wheels have significantly less grip than that.

Re: 375 LBS??
 

Thanks for clarifying that for me. Either way, it still has a huge pushing force. Not shown in the video is me sitting on the carpet (which is FRC carpet) and having the robot push me. I only weigh about 150 lbs, but I would assume the coefficient of friction for jeans on carpet is much higher than chair feet

Re: 375 LBS??
 

Im scared, i dont think our team wants to be pushed around :p

Re: 375 LBS??
 

Going through a few different sources on the internet, it looks like the CoF between aluminum and carpet is somewhere between .3 and .7 (loose average). Let's say .5, and that would give you a pushing force of about 180 pounds. Still very formidable. Welcome to any corrections on the CoF I estimated.

Re: 375 LBS??
 

Nice shooter! Like it. Seems very accurate too! Can't wait to see it at Kansas City!

Re: 375 LBS??
 

Pushing force is a zero sum game. Unless you've discovered some super material with a CoF greater than 1.3 you can exert no more force than any other robot that weighs the same amount.

Re: 375 LBS??
 

What is the source of the 1.3 number?

Re: 375 LBS??
 

We were able to drag two people across the floor with a two sim kitbot without a issue. Better step up your game :). Beautiful chassis BTW

Re: 375 LBS??
 

It's commonly accepted that the "best" tread materials used in FRC give a static CoF of around 1.3.

Re: 375 LBS??
 

Obviously the golden ratio is 33" by 22".

Re: 375 LBS??
 

I bet that's what you guys did. :p