In order to achieve the best possible control of a particular system,
it is clear that as much information about the system as possible shou
ld be used when designing the controller. This leads to a controller s
pecifically tailored to the system being controlled. Unfortunately thi
s is expensive in terms of design time and expertise and a number of a
pproaches have been suggested to overcome this problem. The approach t
aken by physical-model-based control is to model the system in a gener
ic manner and then automatically design the controller based on this m
odel. This process requires symbolic algebra to enable the controller
to be designed.