how to format the codes to compute the differential-algebraic equations using ode15s?

Hi guys,

I’m trying to use ode15s to solve the dynamic model of a mechanical system in the form of

where M is the mass matrix, q is the vector containing all the state variables, F is the generalised force vector, λ is the Lagrange multiplier vector, and is the constraint Jacobian matrix.

To address this problem, I change the system of equations into

where

Then how to format the codes in Matlab? Many thanks!

Answer 1

[Torsten]

I don't see a way to use a MATLAB ode integrator to solve your system.

Take a look at

http://www.unige.ch/~hairer/software.html

Section Mechanical Systems

for suitable solvers.