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#1




Most useful basic equations/reference for FRC/FTC?
So Im making a 1 page quick reference for my team.
If you had a 1 page basic Equation/Reference sheet for FRC/FTC what would you want on it? Things I'm thinking of

#2




Re: Most useful basic equations/reference for FRC/FTC?
Here's a short list of equations that I have used in FRC and FTC:
Code:
Geometry sin^2(x)+cos^2(x)=1 C=2*pi*r Mechanics F=ma (and its angular complement T=I*alpha) at^2+vt+k=x W=Fd (the calculus definition W=integral F ds is also useful) w=mg Electricity V=IR P=VI Gears Ratio = Driving teeth / driven teeth (also true for belts) Center distance = (Pitch Diameter 1 + Pitch Diameter 2) / 2 + Center Add 
#3




Re: Most useful basic equations/reference for FRC/FTC?

#4




Re: Most useful basic equations/reference for FRC/FTC?
DC motor equations

#5




Re: Most useful basic equations/reference for FRC/FTC?

#6




Re: Most useful basic equations/reference for FRC/FTC?

#7




Re: Most useful basic equations/reference for FRC/FTC?
V=I*R
And all of its various derivatives. 
#8




Re: Most useful basic equations/reference for FRC/FTC?
for gears: pitch diameter = # teeth / diametrical pitch
for pullies: pitch diameter = (# teeth * pitch) / pi 
#9




Re: Most useful basic equations/reference for FRC/FTC?
All you need is F = m*a and you can derive the rest.

#10




Re: Most useful basic equations/reference for FRC/FTC?
It appears you're talking about for design time.
Along this line: I'd add some nearpythagorean triplets that are "close enough" to 30 and 45 degree angles to build Versaframe triangles without drilling holes in either gussets or tubes: 30/60/90 triangle: 15^{2} + 26^{2} ~ 30^{2} 45/45/90 triangle: 12^{2} + 12^{2} ~ 17^{2} We used 15/26/30 (actually 7.5", 13", 15") on our 2017 robot and 12/12/17 on our 2018 competition robot; the errors were small enough in both cases that we had no problem fitting the rivets. I have also used 30x26 and 15x13 tiling patterns to make honeycomb wallpaper. Also, as it turns out, the 5/12/13 pythagorean triple is close enough to a 22 1/2 degree angle for many practical purposes. Nickbrickmaster: This really should be ΣF = ma, and you also need F_{reaction} = F_{action}. All the F's and a's should be annotated as vector quantities. Then you can derive the rest. The derivations get shorter if you add ΣΓ = Iα with Γ and α being pseudovectors. I might also add the equation for effective gear ratio of a planetary gearbox with a fixed ring: R_{p} = R_{ring}/R_{sun} + 1. Pneumatic cylinder equation: F=pA [also works for hydraulics, but not useful for FRC). Some energy/work equations! Likely some I'm missing, here are a few:
Edit: even on a onepager, there should be some room for the key numbers of the legal motors (stall and free current, stall torque, free speed, peak power). Also, some conversion factors. Top of the list: 1 rpm ~ 0.1047 radians/sec. Last edited by GeeTwo : 07082018 at 11:30 PM. 
#11




Re: Most useful basic equations/reference for FRC/FTC?
This, if you're a district team

#12




Re: Most useful basic equations/reference for FRC/FTC?
Quote:

#13




Re: Most useful basic equations/reference for FRC/FTC?
There are a bajillion forms of the PID equation people use.

#14




Re: Most useful basic equations/reference for FRC/FTC?
From one of my favorite professors and I'm sure a bunch of other places, here are the fundamental equations for a few different engineering disciplines:
Electrical Engineers: V = I*R (Ohm's Law) Mechanical Engineers: F = M*a (Newton's 2nd Law) Civil Engineers: "if it goes uphill you gotta pump it" (... most civil engineers) 
#15




Re: Most useful basic equations/reference for FRC/FTC?
Quote:

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