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Reset Integrator ODE
Posted Mar 15, 2012, 4:24 a.m. EDT Low-Frequency Electromagnetics, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.2a 0 Replies
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I'm having a problem and need some creative ideas. I switched from rotating machineries to linear actuators. Now my problem is the ODE for the definition of the movement. I use to make a transient analysis:
v: vt[m/s^2]-Fres/m[kg]
Position: Position t -v * (Position<Anker_MaxHub)*(Position>-Anker_MaxHub)
v - velocity
vt - acceleration
Fres - Resulting Force
Anker_MaxHub - is the maximum allowed displacement in one direction.
Everything is o.k. apart from the velocity. I use the expression
(Position<Anker_MaxHub)*(Position>-Anker_MaxHub)
to stop the movement of the actuator when reaching the upper and lower position. When the variable 'Position' isnt within the defined band the change of the position ist multiplied with zero.
My Problem is the velocity. If the actuator reaches the upper or lower position where it cant move on the velocity is still rising as the acceleration is integrated. I need to reset the velocities at that positions to zero. The Matlab Simulink Block "Integrator" has a reset port. I need something similar for COMSOL Multiphysics.
Any ideas?
Hello Gerhard Edmound Stebner
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