[ODE] Neophyte spring mass question

[robert.leclerc at yale.edu]

I am trying to implement a simple particle spring mass system. I don't 
have much experience with the mathematics or the numerical techniques.

I started out using simple euler integration based on some source code 
I found. It uses high daminping and saturation functions to minimize 
instability. I created a box made of spring with springs on the faces 
and dropped it to test it. For small forces it seemed to perform fine 
but when I dropped it from higher positions I noticed it became 
unstable.

Now I figure I either need to run this through a 4th order Runge Kutta 
solver or use ODE. 

1) Would ODE be too heavy weight for something like this since I am 
(*at the moment*) only using particles for the masses. Would ODE be 
faster?

2) If I did implement this in ODE do I just implement the masses as 
simple spheres and then apply the particular forces (given by my 
springs) to their attached bodies on each update step? The reason I am 
asking this is that when I looked over the updtate step with 4th order 
RK code the algorithm itself made several calls (finding k1-k4) to 
find the force exerted by the spring. Thus if I simply apply a force  
to the bodies on each time step this will be untable?

Thanks
Rob Leclerc 



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Rob Leclerc
Yale University
email: leclerc at cpsc.ucalgary.ca
email: robert.leclerc at yale.edu
webpage: www.cpsc.ucalgary.ca/~leclerc
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