Convert Differential Equations to Spate Space

1 次查看(过去 30 天)
I have a system of differential equations, which I would like to convert to spate-space representation:
s = [x(2);
(x(4)*x(6)*(p.Iyy-p.Izz)-(u(1)+u(2)+u(3)+u(4))*p.IR*x(4)...
+(p.b*p.l*(u(2)^2-u(4)^2)))/p.Ixx;
x(4);
(x(2)*x(6)*(p.Izz-p.Ixx)+(u(1)+u(2)+u(3)+u(4))*p.IR*x(2)...
+(p.b*p.l*(u(3)^2-u(1)^2)))/p.Iyy;
x(6);
(x(4)*x(2)*(p.Ixx-p.Iyy)+(p.d*(u(1)^2+u(3)^2-u(2)^2-u(4)^2)))/p.Izz;
x(8);
((p.b*(u(1)^2+u(2)^2+u(3)^2+u(4)^2))*(sin(x(1))*sin(x(5))...
+cos(x(1))*sin(x(3))*cos(x(5))))/p.mass;
x(10);
((p.b*(u(1)^2+u(2)^2+u(3)^2+u(4)^2))*(cos(x(1))*sin(x(3))*sin(x(5))...
-sin(x(1))*cos(x(5))))/p.mass;
x(12);
((p.b*(u(1)^2+u(2)^2+u(3)^2+u(4)^2))*(cos(x(1))*cos(x(3)))-p.mass*p.g)/p.mass];
The confusing moment for me is that there are multiplication of state variables (e.g. x(4)*x(6)), so I don't know how to write it down in A matrix.
Is it possible to convert such system to state-space? Could you hint the way how it should look like?
Thank you in advance for your answer!

采纳的回答

Star Strider
Star Strider 2019-7-9
In order to convert your equations to a state-space representation, you need to linearise them. This involves taking the Jacobian. I refer you to Linearization of Nonnlinear Systems to guide your efforts. The Symbolic Math Toolbox (that was not available when I encountered this) can likely help you significantly.
There are several other such references that reveal themselves in an Interweb search.

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 MATLAB 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by