Sven, A stiffness matrix is only relevant when you have a system that is described by linear differential equations. In the general, non-linear form of the equations of motion of a rigidbody system there is only one matrix that can be extracted, i.e. the matrix of coefficients for the accelerations, the mass matrix. You can always linearize you system of equations and then find the coefficients of the generalized speeds and coordinates to get the damping and stiffness matrices, respectively.
Jason moorepants.info +01 530-601-9791 On Thu, Jul 21, 2016 at 1:08 AM, <kassb...@gmail.com> wrote: > from sympy.physics.mechanics import * > > provides: > LM = LagrangesMethod(L, [q1, q2]) > > and: > LM.mass_matrix > > i.e. a matrix of some coefficients... > > Why is there no: > LM.stiffness_matrix > > i.e. a matrix of some other coefficients...? > > Regards, > Sven > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sympy+unsubscr...@googlegroups.com. > To post to this group, send email to sympy@googlegroups.com. > Visit this group at https://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/1a0ccccf-bc06-4644-9000-1706642117da%40googlegroups.com > <https://groups.google.com/d/msgid/sympy/1a0ccccf-bc06-4644-9000-1706642117da%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAP7f1AgD%3D8r2Y7DmUApDoni%2BN56Gxrh0xhbuUSexsh%2BOgqPLSQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.