As far as I can tell, I have correctly added a torque term at the "P" joint. The linearization produces the matrices of expected dimension. I haven't checked that the "A" matrix is correct, but it looks like the "B" matrix is not correct.
Here's a gist that computes "B" using the linearize() method (stored in B2), and also in the way that I expect B to be computed (stored in B1) https://gist.github.com/1665634 On Jan 19, 3:07 pm, Gustavo <gustavo.goret...@gmail.com> wrote: > I found this example [1], which is very helpful. All I need is a > torque term at the "P" joint. > Then when I linearize the equations of motion, I hope to get a 4-by-4 > "A" matrix and a 4-by-1 "B" matrix. > > [1]http://pydy.org/index.php?title=Double_Pendulum#Integration_with_Scipy > > On Jan 18, 3:41 pm, Gustavo <gustavo.goret...@gmail.com> wrote: > > > > > > > > > I'm looking to use the physics.mechanics module to get the equations > > of motions for adoublependulumactuated at the center joint, and get > > the linearized dynamics about certain points. I know that this can be > > done using the Lagrangian, but I'd like to try to use the mechanics > > module. > > > I see the examples here [1] but I am having trouble applying that to > > thedoublependulum. I have only an introductory classical mechanics > > background, so I'm hoping that the mechanics module will let me > > assemble a dynamical system, impose some constraints, and then > > generate the equations of motion. > > > Thanks, > > Gustavo > > > [1]http://docs.sympy.org/dev/modules/physics/mechanics/examples.html -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
