how to get the state-space representation from the SimMechanic model?

Physical model is built with SimMechanics, but if try to control it such as LQR method, need to know the state equation of the model, so as to calculate the control rate. However if the equations are derived by hand can directly with the simple Simulink block to simulation. Use this procedure I feel that there is no need to bother to build a physical model of SimMechanics.So I think that there must have a better way to get the state-space representation from the SimMechanic model.I'm a learner of SimMechanicas，and I encounter this problem.It would be better if you could give me some simple examples.Thanks。

Answer 1

[Fei Deng]

You can linearize a simscape model and get the state space representation. Take a look of the example in help documentation showing how to linearize a hydraulic plant model to support control system stability analysis and design. http://www.mathworks.com/help/physmod/simscape/ug/linearize-a-plant-model-for-use-in-feedback-control-design.html

[Friedrich Wegmann]

But is there a way to directly get the system matrices A,B,C,D?

Answer 2

[Sergey Kasyanov]

Hello!

Try to use linmode.