Tetra Math

[n0cturnalxb]

Originally Posted by Levin571

does anyone know how many tetra's can be fit under one of the goal by any chance?

Considering the goals (aside from the center one) are about 5'3" = 63"(.. that's almost as tall as I am! .. ugh, I feel short now) and each tetra is 2'4" = 28" ...

Let's say each tetra raises the stack about 3"?

And you need about 28" clearance left to fit the last tetra in ...

4? That doesn't sound right. 7ish-9ish?

I think I just fried my sleep-deprived brain.


(edit) Err, cross that out .. I mean around 4-6 maybe per stack.. maybe.. assuming each tetra raises each stack 3". I think. Someone check my math or logic or something, brain's not working well right now..

Assuming you can fit 4 perfect stacks of 4 inside the goal, that's 16.

I'd say go with stacking on top of the goal.. go for containing if you're having a lot of problems with designing the arm, but stacking will give you three times the amount of points you can get by containing .. and the possibility of making a row.

[Dillon Compton]

Originally Posted by n0cturnalxb

Considering the goals (aside from the center one) are about 5'3" = 63"(.. that's almost as tall as I am! .. ugh, I feel short now) and each tetra is 2'4" = 28" ...

Let's say each tetra raises the stack about 3"?

And you need about 28" clearance left to fit the last tetra in ...

4? That doesn't sound right. 7ish-9ish?

I think I just fried my sleep-deprived brain.


(edit) Err, cross that out .. I mean around 4-6 maybe per stack.. maybe.. assuming each tetra raises each stack 3". I think. Someone check my math or logic or something, brain's not working well right now..

Assuming you can fit 4 perfect stacks of 4 inside the goal, that's 16.

I'd say go with stacking on top of the goal.. go for containing if you're having a lot of problems with designing the arm, but stacking will give you three times the amount of points you can get by containing .. and the possibility of making a row.

According to the kickoff, each tetra raises the stack approx. six inches.

[sojouner06]

one tetra added to the goal is a height increase of exactly 3.5 inches. Therefore, if you just add about 5 tetra's, thats about another foot and a half. So if you have an arm, you would need to have a 10.5 foot at full extension to out class other arms

[Max Lobovsky]

Originally Posted by sojouner06

one tetra added to the goal is a height increase of exactly 3.5 inches.

Where did you get that? From pictures (and according to Dillon Compton) it looks much closer to 6" per tetra.

[Ryan F.]

It is 6 inches per tetra...this is comming from someone who's seen them built and stacked on eachother.

[sojouner06]

i calulated using a formula i learned in statistics, the width of the pole vs height/ complicated math suff

[sojouner06]

pole=pvc pipe

[sojouner06]

i made tetra's too and did see that it was 3.5, ill go see if the tetra's was built properly

[elknise]

sojouner06, try to edit your posts instead of creating new ones.
ftp://67.170.35.253/robotics/Posting.swf

Anyways, did you take into consideration about the end-caps. Also, when looking at the sidelines during the kickoff, it looked more like 6 inches.

[HPA_Robotics_13]

I thought that the tetras used at the actual competitions don't have PVC endcaps but instead have flat pieces that screw into the PVC?

[Greg Needel]

i was in manchester and saw the offical ones and adding them ontop of each other adds SIX inches....i also tested the how many fit under a goal and 7 perfectly stacked will make it as long as there are no tetras ontop of the goal. if there is a tetra ontop of the goal then you can only fit 4 under

[unapiedra]

Originally Posted by Greg Needel

if there is a tetra ontop of the goal then you can only fit 4 under

Why that? Does the tetra ontop block that?

[rangersteve]

I wish i had seen this thread sooner. I had to do this math today but oh well i like math. Nice thread.

[tkwetzel]

Originally Posted by HPA_Robotics_13

I thought that the tetras used at the actual competitions don't have PVC endcaps but instead have flat pieces that screw into the PVC?

The small tetras have flat clover pieces that screw into the end caps attached to the PVC. The goals are aluminum and will have a angled piece of hardware holding them together. These pieces are visible in the field drawings available on FIRST's documents page.

[Aignam]

Originally Posted by tkwetzel

The small tetras have flat clover pieces that screw into the end caps attached to the PVC. The goals are aluminum and will have a angled piece of hardware holding them together. These pieces are visible in the field drawings available on FIRST's documents page.

In addition, a good picture of these pieces can be located here.