Solving a Mass Spring Damper System with Lagrange Equation

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SUMMARY

This discussion focuses on solving a mass spring damper system using the Lagrange equation. The user encountered difficulties in formulating the equation of motion, particularly when attempting to apply the State Space Approach with an initial condition of mass set to zero. Key challenges include determining kinetic and potential energy, as well as identifying the correct variables for spring constants K1, K2, and damping coefficient C1. A resource from the University of Ottawa is provided to assist with these concepts.

PREREQUISITES
  • Understanding of Lagrangian mechanics
  • Familiarity with spring-mass-damper systems
  • Knowledge of State Space Approach in dynamics
  • Ability to compute kinetic and potential energy in mechanical systems
NEXT STEPS
  • Study the derivation of the Lagrange equation for mechanical systems
  • Learn how to formulate equations of motion for multi-mass systems
  • Explore the application of the State Space Approach in solving dynamic systems
  • Review resources on kinetic and potential energy calculations in spring-mass systems
USEFUL FOR

Students in dynamics courses, mechanical engineers, and anyone interested in advanced dynamics and control systems analysis.

Lelak
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Hello!

I am taking a course in dynamics and have a question about a spring-mass-damper system (see the attached file) that I want to solve using Lagrange equation (see attached file).

I am having trouble writing the equation of motion for this problem. At first I tried doing it the way I would for a system with two masses, connected by springs and dampers. This gave me a system of equations which I then used the State Space Approach on. I set the first mass=0, only to realize that I would not be able to get the homogenous solution this way.

Any help is appreciated! Thank you very much!
 

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If this is homework, it would be best to put it in that section where you receive a more thorough response, with some description of where you are actually having a problem. ie finding the kinetic energy, potential energy, the "x" to be used for K1, K2, and C1. what have you tried and where are you stuck.

Anyways here is a site that might help you out a bit more, from the University of Ottawa, Ontario, Canada.
http://www.site.uottawa.ca/~rhabash/ELG4152L10.pdf
 
256bits said:
If this is homework, it would be best to put it in that section where you receive a more thorough response, with some description of where you are actually having a problem. ie finding the kinetic energy, potential energy, the "x" to be used for K1, K2, and C1. what have you tried and where are you stuck.

Anyways here is a site that might help you out a bit more, from the University of Ottawa, Ontario, Canada.
http://www.site.uottawa.ca/~rhabash/ELG4152L10.pdf

Okay, I will repost this under the homework section! Thank you!
 
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