Unstable equilibria
Posted: Tue Aug 15, 2023 1:04 am
Hello,
First of all, I would like to thank you for developing and making this incredible simulation library available.
I am trying to analyze the stability of some systems. Until now, the models were quite simple and I could find the EOM manually, but I am using Simbody for more complex models. I read the SimTK::LocalEnergyMinimizer finds local equilibria by minimizing the potential energy locally, and therefore I assume it can only find stable equilibria?
In this case, I should define a function qdotdot(qdot,q), from which later I can find q*->qdotdot(0,q*)=0 and differentiate at q* to obtain the linearized system matrix. How can I do it? I guess I should be able to using functions from SimTK::SimbodyMatterSubsystem. Or is there an alternative?
Thank you!
Marc
First of all, I would like to thank you for developing and making this incredible simulation library available.
I am trying to analyze the stability of some systems. Until now, the models were quite simple and I could find the EOM manually, but I am using Simbody for more complex models. I read the SimTK::LocalEnergyMinimizer finds local equilibria by minimizing the potential energy locally, and therefore I assume it can only find stable equilibria?
In this case, I should define a function qdotdot(qdot,q), from which later I can find q*->qdotdot(0,q*)=0 and differentiate at q* to obtain the linearized system matrix. How can I do it? I guess I should be able to using functions from SimTK::SimbodyMatterSubsystem. Or is there an alternative?
Thank you!
![Smile :)](./images/smilies/icon_e_smile.gif)
Marc