Equations of motion of a system with non holonomic constraints

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The discussion focuses on deriving the equations of motion for a system with two degrees of freedom subject to two non-holonomic constraints represented by the equations A1 dq1 + C dq3 + D dq4 = 0 and A2 dq1 + B dq2 = 0. The constants A1, A2, B, C, and D are independent of the generalized coordinates. The discussion emphasizes that treating these constraints as holonomic would be incorrect, and suggests using Lagrange multipliers to solve the problem. The constraints matrix must have a rank of 2 to ensure the system's motion is accurately described.

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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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