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Old March 14th, 2019, 09:15 AM   #2
Peter Nachtwey
United States

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Join Date: Apr 2002
Location: Vancouver, WA, US
Posts: 6,939

Originally Posted by cheeco View Post
I put in quite some work and effort to develop this trajectory generator. The problem is way more tricky than it initally looks, as there are many different cases to consider. Finding a stable mathematical solution is also not straightforward.
Wow! People have no idea what it takes to write a good third order target generator. The target generator is the most complicated part of a motion controller.

I have my own version that I will use to compare solutions when I get to work. I wrote a program to test different combinations of starting stoping and limits. I ran it for 200,000,000,000+ combinations to test mine. It took days. It is impossible to be thorough using human testing.

I do not have my test cases because I am home. I will test your target generator over the weekend. Most of the hard cases are short moves where no limit is reached.

Meanwhile, just so the people here know what it takes to do this will provide this link.
Even the simple case requires solving 17 equations for 17 unknowns! Try solving that in a PLC!

Good job!
"Living is easy with eyes closed, misunderstanding all you see...." Strawberry Fields Forever, John Lennon
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