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        <title>Simplifying equations - Help required</title>
        <description> Its been years since I did any complex transformation of formulae. Could someone help.

Is there a way to simplify the following formulas , preferably to remove some of the square or square roots?
They are transforms for my delta robot.

For non programmers 
pow(x,2) is x squared
sqrt(x) is the square root of x
0.866025 is my approximation of Sin 60 if that helps.

T1 = sqrt(pow(F,2) - pow(sqrt(pow((J * -0.8660254) - (x - (V * 0.8660254)),2) + pow((J * -0.5) - (y + (V * -0.5)),2)),2)) + z;

T2 = sqrt(pow(F,2) - pow(sqrt(pow((J * 0.8660254) - (x + (V * 0.8660254)),2) + pow((J * -0.5) - (y + (V * -0.5)),2)),2)) + z;

T3 = sqrt(pow(F,2) - pow(sqrt(pow(0 - (x),2) + pow(J - (y + V),2)),2)) + z; 


I&#039;m offering a pure maths degree from the University of Delta Robot for the first correct answer!</description>
        <link>https://reprap.org/forum/read.php?1,68467,68467#msg-68467</link>
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            <guid>https://reprap.org/forum/read.php?1,68467,68509#msg-68509</guid>
            <title>Re: Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68509#msg-68509</link>
            <description><![CDATA[ It is unlikely the angles will change as my design is triangular, so the angles between the towers are 120 degrees.<br />
<br />
If you want to take a look at the design go to the link below and also a video on youtube of it working. I'm just tidying up the firmware, hence the drive to simplify the equations.<br />
<br />
<a href="http://www.heliumfrog.net63.net/deltarobot/delta.html" target="_blank"  rel="nofollow">Helium Frog Website</a><br />
<br />
There is also an excel spreadsheet which performs the calculations <br />
<br />
<a href="http://www.heliumfrog.net63.net/deltarobot/details/delta_movement_calculator.xls" target="_blank"  rel="nofollow">Excel document</a>]]></description>
            <dc:creator>martinprice2004</dc:creator>
            <category>General</category>
            <pubDate>Thu, 16 Dec 2010 07:16:20 -0500</pubDate>
        </item>
        <item>
            <guid>https://reprap.org/forum/read.php?1,68467,68508#msg-68508</guid>
            <title>Re: Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68508#msg-68508</link>
            <description><![CDATA[ I had a feeling that was the case (re: sin 30).<br />
<br />
I'll take a further look at it tomorrow and see if I can come up with anything.<br />
<br />
BTW: One of the reasons for asking is that some combinations of sin/cos formulas can be transformed into other combinations, which might be easier for you to calculate.<br />
<br />
Do you ever see that angle (60 in one, 30 in the other) changing?]]></description>
            <dc:creator>Cefiar</dc:creator>
            <category>General</category>
            <pubDate>Thu, 16 Dec 2010 06:14:37 -0500</pubDate>
        </item>
        <item>
            <guid>https://reprap.org/forum/read.php?1,68467,68505#msg-68505</guid>
            <title>Re: Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68505#msg-68505</link>
            <description><![CDATA[ 0.5 is sin 30 in these equations<br />
<br />
I'm trying to do all the calculations in an arduino mega firmware, that way I can use off the shelf PC G Code software to drive the robot. <br />
<br />
Is there any stuff on the net how to calculate the curve fits for these equations?]]></description>
            <dc:creator>martinprice2004</dc:creator>
            <category>General</category>
            <pubDate>Thu, 16 Dec 2010 05:12:31 -0500</pubDate>
        </item>
        <item>
            <guid>https://reprap.org/forum/read.php?1,68467,68501#msg-68501</guid>
            <title>Re: Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68501#msg-68501</link>
            <description><![CDATA[ I think that this is precisely why it would be better to transfer details regarding step timing to the controller rather than coordinates as is done with the current g-code implementation. Then you could do all of this heavy lifting maths in your PC and just come up with some curve-fitted approximations to the desired step timing sequence. The controller could then implement the step timing synchronously and I think that would result in better, more consistent quality prints with less blobs and warts.]]></description>
            <dc:creator>Greg Frost</dc:creator>
            <category>General</category>
            <pubDate>Thu, 16 Dec 2010 04:04:02 -0500</pubDate>
        </item>
        <item>
            <guid>https://reprap.org/forum/read.php?1,68467,68476#msg-68476</guid>
            <title>Re: Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68476#msg-68476</link>
            <description><![CDATA[ As a first look, it seems that in the middle segment of each equation, you have a squared square root.<br />
<br />
eg: pow(sqrt(  _____ pow((J * -0.8660254) - (x - (V * 0.8660254)),2) + pow((J * -0.5) - (y + (V * -0.5)),2) _____ ),2)<br />
<br />
You should be able to eliminate that straight away.<br />
<br />
PS: Closing bracket indicators in text editors are your friends here.<br />
<br />
Q's:<br />
<br />
Is that actually 0.5 in these formulas, or is it a pre-generated value of something say like sin(30) ??<br />
<br />
Do you need to generate T1 thru T3 for the same set of values? There's quite a bit of commonality between them, so you could probably break them down into common parts and substitute here and there.]]></description>
            <dc:creator>Cefiar</dc:creator>
            <category>General</category>
            <pubDate>Wed, 15 Dec 2010 17:18:13 -0500</pubDate>
        </item>
        <item>
            <guid>https://reprap.org/forum/read.php?1,68467,68467#msg-68467</guid>
            <title>Simplifying equations - Help required</title>
            <link>https://reprap.org/forum/read.php?1,68467,68467#msg-68467</link>
            <description><![CDATA[ Its been years since I did any complex transformation of formulae. Could someone help.<br />
<br />
Is there a way to simplify the following formulas , preferably to remove some of the square or square roots?<br />
They are transforms for my delta robot.<br />
<br />
For non programmers <br />
pow(x,2) is x squared<br />
sqrt(x) is the square root of x<br />
0.866025 is my approximation of Sin 60 if that helps.<br />
<br />
T1 = sqrt(pow(F,2) - pow(sqrt(pow((J * -0.8660254) - (x - (V * 0.8660254)),2) + pow((J * -0.5) - (y + (V * -0.5)),2)),2)) + z;<br />
<br />
T2 = sqrt(pow(F,2) - pow(sqrt(pow((J * 0.8660254) - (x + (V * 0.8660254)),2) + pow((J * -0.5) - (y + (V * -0.5)),2)),2)) + z;<br />
<br />
T3 = sqrt(pow(F,2) - pow(sqrt(pow(0 - (x),2) + pow(J - (y + V),2)),2)) + z; <br />
<br />
<br />
I'm offering a pure maths degree from the University of Delta Robot for the first correct answer!]]></description>
            <dc:creator>martinprice2004</dc:creator>
            <category>General</category>
            <pubDate>Wed, 15 Dec 2010 14:19:14 -0500</pubDate>
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