Coupled Oscillator: Coupled Mass-Spring System with Damping: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
No edit summary |
||
Line 29: | Line 29: | ||
For mass 1: |
For mass 1: |
||
<math> + \uparrow \sum F_{y_1} = m_1 \ddot{x}_1 \Rightarrow\ m_1 \ddot{x}_1=- |
<math> + \uparrow \sum F_{y_1} = m_1 \ddot{x}_1 \Rightarrow\ m_1 \ddot{x}_1=-2b_1\dot{x}_1-k_1s_1+k_2s_2+m_1g</math> |
||
For mass 2: |
For mass 2: |
||
<math> + \uparrow \sum F_{y_2} = m_2 \ddot{x}_2 \Rightarrow\ m_2 \ddot{x}_2=- |
<math> + \uparrow \sum F_{y_2} = m_2 \ddot{x}_2 \Rightarrow\ m_2 \ddot{x}_2=-2b_2\dot{x}_3-k_2s_2+m_2g</math> |
||
Line 47: | Line 47: | ||
<math> \ddot{x}_1= - \frac{ |
<math> \ddot{x}_1= - \frac{2b_1}{m_1} \dot{x}_1 - \frac{k_1}{m_1}l_1 - \frac{k_1}{m_1}x_1 + \frac{k_2}{m_2}l_1 + \frac{k_2}{m_2}x_2 + g </math> |
||
and |
and |
||
<math> \ddot{x}_2= - \frac{ |
<math> \ddot{x}_2= - \frac{2b_2}{m_2} \dot{x}_2 - \frac{k_2}{m_2}l_2 - \frac{k_2}{m_2}x_2 + g </math> |
Revision as of 14:35, 29 November 2009
Problem Statement
For the below system set up a set of state variable equations, and then solve using Laplace transformations. Assume all motion takes place in the vertical directions.
Initial Values
For the upper mass:
And for the lower mass:
Find the Force Equations
First we need to sum forces in the y-direction for each block.
For mass 1:
For mass 2:
For the cases above
and
where l is the unstretched length of the spring and x is the displacement of the spring.
So if we put the equations above into the correct form we have:
and