Equations of motion of a system with non holonomic constraints

AI Thread Summary
The discussion focuses on deriving equations of motion for a system with two degrees of freedom and two non-holonomic constraints. The constraints are expressed through specific equations involving generalized coordinates and independent constants. Participants clarify that treating these constraints as holonomic would be incorrect, emphasizing the need to consider their non-holonomic nature. The importance of the rank of the constraints matrix being two is also highlighted. The conversation aims to guide the user on how to approach the problem using Lagrange multipliers and integration techniques.
DannyJ108
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Homework Statement
A system with 2 degrees of freedom has 2 non holonomic constraints. Determine the equations of motion that can describe the movement of such system
Relevant Equations
##A_1 dq_1 +Cdq_3 + Ddq_4 = 0##
##A_2 dq_1 + Bdq_2 = 0##
Hello,

I have a system with 2 degrees of freedom with 2 non-holonomic constrains that can be expressed by:##A_1 dq_1 +Cdq_3 + Ddq_4 = 0##

##A_2 dq_1 + Bdq_2 = 0##Being ##q_1, q_2, q_3## and ##q_4## four generalized coordinates that can describe the movement of the system. And ##A_1, A_2, B, C## and ##D## independent constants.I have to obtain the necessary equations to completely describe the system's motion and interpret the physical meaning of the different equations.How should I proceed? I think I should use Lagrange multipliers, but I don't know where to start.Thanks for the help.
 
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If A,B,C,D are constants then the constraints are holonomic. Integrate these equations:
$$ A_1 q_1+Cq_3+Dq_4=const_1,\quad A_2q_1-Bq_2=const_2$$ express from here for example ##q_1,q_2## and get the system with generalized coordinates ##q_3,q_4##
 
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wrobel said:
If A,B,C,D are constants then the constraints are holonomic. Integrate these equations:
$$ A_1 q_1+Cq_3+Dq_4=const_1,\quad A_2q_1-Bq_2=const_2$$ express from here for example ##q_1,q_2## and get the system with generalized coordinates ##q_3,q_4##

The homework statement specifically says that the constants are non holonomic, so approaching them as holonomic would be wrong I think.
Also, I didn't mention it, but it says that ##A_1, A_2, B, C## and ##D## are constants independent of the generalized coordinates. I'm not sure if it makes a difference in the way to resolve the exercise.
I'll try the approach you mentioned.
 
DannyJ108 said:
Also, I didn't mention it, but it says that and are constants independent of the generalized coordinates
you have said this:
DannyJ108 said:
Homework Statement:: A system with 2 degrees of freedom has 2 non holonomic constraints. Determine the equations of motion that can describe the movement of such system
Relevant Equations:: A1dq1+Cdq3+Ddq4=0
A2dq1+Bdq2=0

. And and independent constants.
By the way the rang of constraints matrix must be 2
 
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