PCB Heaven
General Category => Maths, Geometry, Physics and others => Topic started by: sysKo on May 27, 2009, 18:01:16 PM

I do not know where to put this question, hear or in the CNC? Anyway.
I (re)ask again for this. I have a part of the arc. I want to calculate the radio of the arc. The height of the arc i know it. How to calculate it?
K.

It's a good board the one you chose to post your question.
So... I think you are missing of something. The given data are not enough. We need either the angle of the arc, or the chord of the arc... Please specify.
My regards ;)

Chord is the open? You know... The open of the door

I suppose you want to calculate the radius of the arc, by knowing the arch chord (AKA door width  left space  right space) and by knowing the ark height.
For the people here to understand, because our conversation looks like an encoded signal, i have attached a file...
So, first to calculate the Semi_Chord. That would be the Chord divided by two:
SC = C/2
Then, the radius can be easily calculated using the following formula:
R = H^{2} + SC^{2} / 2H
I asked you to write it down not to forget. But now you can find it here whenever you want :P

Thanks you Georg. Is this that i am look!!!!! :o 8) ;D :D ;) :) :*

Thanks you Georg. Is this that i am look!!!!! :o 8) ;D :D ;) :) :*
yes is this :D
I know ;)

And for the draw with 3 circles? The "perispomenh"? I am sorry i do not know the english name.

Perpendicular is the name. I told you you should write them down ;)
Rtotal = H^{2}+SC^{2} / 2*H
Rin = Rtotal * L
Rout = RtotalRin...

And i understand you think by this? ??? ??? ??? ??? ??? ???

You should!
Anyway.
Consider as it was a single arc (like the first drawing attached).
The radius (that i call Rtotal) should be
Rtotal = H^{2}+SC^{2} / 2*H
But now you have a parameter L, that is a number from 0 to 1. Use 0.5. You'll get what this is when time comes.
So, the internal arc will have a radius of:
Rin = Rtotal * L
and the external 2 arcs will have rad:
Rext = Rtotal  Rin
Is that clear now?

I still make china symbols with it :( :( :( :( :( :( :( :(
Am i stupid?

In the name of holy mary madonna
See attached image:
The Semicord SC is half the width (left to right) of the drawing.
The Height H is user defined
The proportion L (LOGOS in Greek is also user defined, at about 0.5 or so...)
R_{OL}=(H^{2} + SC^{2})/2H
Rin = ROL*L
Rex = ROLRin
Ok So far?
Now:
X2 = X1 + H * L
X3 = X1 + L
Y2 = Y1 + SC * L

That's the problem with CNC, they go along with maths, otherwise is just a big router.:)

That's the problem with CNC, they go along with maths, otherwise is just a big router.:)
That's the problem with operators.... not cnc... You need maths also with the hand routers. If you want to be a good operator, you need maths. Kostas (sysKo) is a "wanna be" good operator, but because of his believes that he needs no maths, he will never be above average.

Correct, i mean just something to cut straight lines. :)

Correct, i mean just something to cut straight lines. :)
a band saw or something

Yeah, something like that. Having a spaceship and using it as a bike. :)

In the name of holy mary madonna
See attached image:
The Semicord SC is half the width (left to right) of the drawing.
The Height H is user defined
The proportion L (LOGOS in Greek is also user defined, at about 0.5 or so...)
R_{OL}=(H^{2} + SC^{2})/2H
Rin = ROL*L
Rex = ROLRin
Ok So far?
Now:
X2 = X1 + H * L
X3 = X1 + L
Y2 = Y1 + SC * L
THAT IS IT!!!!!!!!!!!!! I WORK NOW!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! THANKS YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
:* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :* :*

now yes!!!!! ;D

you are too kind and mostly welcomed