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<font size="-1"><font face="Verdana">Hello,<br>
<br>
I use Ipopt for Optimal Control (minimum time control) and in one of my
applications, the convergence is very slow. <br>
It is a robotic application (4 dof), the equations (constraints and
gradient of constraints, </font></font><font size="-1"><font
face="Verdana">automatically generated by Maple</font></font><font
size="-1"><font face="Verdana">) are very big so it could be the
reason but on another hand, in another application (5 dof), the
convergence is fast (< 2000 iterations, less than 2 minutes).<br>
In this application (4 dof),</font></font><font size="-1"><font
face="Verdana"> I tried up to 20000 iterations and it did not converge
yet. Each time I increase max_iter, it is better (the minimum time
decreases and the controls are closer to saturations) so a possibility
would be to try to put a very high max_iter and wait for a few hours.<br>
But I would like to know if another option could make the convergence
faster. Maybe it is a problem of scaling or something else ?<br>
<br>
Thanks in advance,<br>
Best regards,<br>
<br>
Nicolas Gachadoit<br>
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