LEGO NXT, Simulink, Loading crane

Hello,

I need help with the NXT and Simulink. I don't know how to implement trolley from a loading crane in Simulink. I have two differential equotations. What do I have to do now for a good control system so that the load will not begin to oscillate while the trolley is driving?

If somebody already did something like that it would be very nice to get the program for learning from it.

Kind regards Peter