Bots and Simulations > Evolution and Internet Sharing Sims
Its almost the day guys
Sprotiel:
--- Quote ---I'm too busy working on instabilities in my Euler method for tie force integration.
--- End quote ---
What do you need Euler method for? It seems quite complicated compared to the simplistic physics model we have in the other parts of the simulation.
Numsgil:
:lol:
Euler's is what we use in the other parts of the program.
velocity = velocity + acceleration is Eulers. It has inherant instabilty because you're measuring things in finite steps. After n many steps you're no longer correct.
PurpleYouko:
Yup. That's why you can't model a basic orbit program using this kind of math. The forces that should be acting on the moving objects between the start location and the end location are just completely ignored. :rolleyes:
Numsgil:
I'm working on ties, and I had a bug where after about a thouand cycles any two tied bots would fly off in one direction. I thought it was due to Euler error, but I still had it after implementing a Runge-Kutta method.
Then I figured out its because I update robot 1's position, then I update robot two's distance from robot 1 and apply forces to robot two. That's probably the same problem I reported with ties a while back (remember the triangle bot that started flying across the screen unpredicatably?)
Hooke tie physics is now much cleaner and smoother. Stifftie can be made to work like it should.
Sprotiel:
:redface: I was thinking of the Gauss method of integration...
Anyway, Euler method is good enough for molecular dynamics, so it should be good enough for DB. However, the algorithm to use is
1. Compute forces acting on all particles (including the effect of collisions)
2. Update positions and velocities.
It's not what happens in DB right now and I guess it causes many problems.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version