  Detailed models of observed interacting galaxies suffer from the extended
parameter space. Here, we present results from our code MINGA which couples an
evolutionary optimization strategy (a genetic algorithm) with a fast N-body
method. MINGA allows for an automatic search of the optimal region(s) in
parameter space within a few hours to a few days of CPU time on a modern PC by
investigating of the order of 10^5 models. We demonstrate its applicability by
modelling the HI intensity and velocity maps of the interacting system M51 and
NGC 5195. We get a good fit for the HI intensity map and we can reproduce the
counter-rotation feature of the HI arm. Our result corroborates the results of
Salo & Laurikainen (2000) who favour a model with multiple passages through
M51's disk.
