Deriving Equations of Motion for Compound Pendulum with 3 DOF

AI Thread Summary
The discussion focuses on deriving the equations of motion for a compound pendulum with three degrees of freedom (DOF). The user is familiar with using Lagrangian mechanics for simple pendulums and seeks clarification on whether the system is a 3D conical pendulum or a 2D plane pendulum composed of three interconnected rods. The pendulum is described as a single irregular body with a 3x3 inertia tensor, fixed at a point and capable of movement in a 3D coordinate system. The key challenge lies in accurately modeling the motion with the specified degrees of freedom. Understanding the configuration of the pendulum is crucial for deriving the correct equations of motion.
msntito
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Can anyone help?
I have to derive eq of motion of a compound pendulum with 3 rotational dof.
I know how to do it, for simple pendulum (using Lagrangian's).
 
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Is it literally a 3d (or conical) pendulum, or a 2d (plane) pendulum made of 3 rods, each with tied to the other by a junction point (thus with 3 degrees of freedom) ?
 
It is a single body (irregular shape with an Inertia tensor 3x3), fixed at a point, say O and can move in 3d rectangular coord system (3 rotational DOF...say alpha beta gamma).
 

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