Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Gear predictor / corrector

  1. Mar 8, 2009 #1

    I am working on a personal project that models the movement of pedestrians in large crowds. I am using something called the "social force model" and came across a master's thesis which describes an improved implementation. The model constructs a very large force equation to model the way people try to avoid each other / stationary objects as they navigate busy areas. In this case, a very large force equation to describe the acceleration of each pedestrian is developed (F=ma, assuming unit mass).

    As I read the thesis, the authors described that they implemented the model using Gear's predictor/corrector to do the integration. The problem is that the Gear method requires first and second derivatives of the force equation (dV/dt), yet the equation itself is not explicitly described in terms of time.

    I'm rusty on my phyics / diff eq's, so I suspect this is simpler than it appears to me. The thesis can be found at:

    http://public.rz.fh-wolfenbuettel.de/~apel/files/thesis.pdf" [Broken]

    The model is described on pages 21-26 and the Gear implementation is on 28 and 29.

    Again, this can't be as hard as it appears to me. Any suggestions?
    Last edited by a moderator: May 4, 2017
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?