Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Peter Stahlecker
Dear Jason, Now all clear to me, thanks! Peter Am Do., 3. Feb. 2022 um 10:39 Uhr schrieb Jason Moore : > Peter, > > Yes, the velocity constraints work the same way. There are reaction forces > that constrain the velocities. > > Jason > moorepants.info > +01 530-601-9791 > > > On Thu, Feb 3,

Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Jason Moore
Peter, Yes, the velocity constraints work the same way. There are reaction forces that constrain the velocities. Jason moorepants.info +01 530-601-9791 On Thu, Feb 3, 2022 at 10:37 AM Peter Stahlecker wrote: > Dear Jason, > > Thanks! > If I understood correctly, if I use velocity

Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Peter Stahlecker
Dear Jason, Thanks! If I understood correctly, if I use velocity constraints, I do not use the minimal number of generalized coordinates, hence these reaction forces and 'virtual' speeds appear in my force term of the equations of motion. As they are normal to the motion of the particle(s), I

Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Jason Moore
Peter, If you have a particle that is forced to move along a path (typically be a configuration constraint), then there exists reaction forces normal to the path that keep it on the path. These forces are not present in the equations of motion when they are formed with minimal coordinates. But

Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Peter Stahlecker
Thanks! Would I also set the 'reaction forces' appearing in the force term equal to zero? As per my understanding of mechanics, they also should have no influence on the equations of motion (?) moore...@gmail.com schrieb am Donnerstag, 3. Februar 2022 um 09:59:53 UTC+1: > The virtual speeds

Re: [sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Jason Moore
The virtual speeds will appear in the force equations, but you then just set them to zero because they are fictitious. You force equation should then be correct. Jason moorepants.info +01 530-601-9791 On Thu, Feb 3, 2022 at 9:58 AM Peter Stahlecker wrote: > When I use a velocity constraint to

[sympy] sympy.physcis.mechanics // reaction force

2022-02-03 Thread Peter Stahlecker
When I use a velocity constraint to force a particle not to move in a certain direction, there must be a 'reaction force' on the particle. I use KM.auxiliary_eqs to find reaction forces, which works very well in general! However, if I try to find the reaction force due to a velocity