  In dynamic simulation of complete wheel loaders, one interesting aspect,
specific for the working task, is the momentary power distribution between
drive train and hydraulics, which is balanced by the operator.
  This paper presents the initial results to a simulation model of a human
operator. Rather than letting the operator model follow a predefined path with
control inputs at given points, it follows a collection of general rules that
together describe the machine's working cycle in a generic way. The advantage
of this is that the working task description and the operator model itself are
independent of the machine's technical parameters. Complete sub-system
characteristics can thus be changed without compromising the relevance and
validity of the simulation. Ultimately, this can be used to assess a machine's
total performance, fuel efficiency and operability already in the concept phase
of the product development process.
