An alternative approach to the development of control systems is presented. It differs from current ones in two aspects, because it is based on a formal software specification language, which allows formal verification and because it enables multidisciplinary development of a control system as existing control models can be easily incorporated in the discussed approach. Simulation of ASTRAL specifications is discussed. Simulation, as opposed to verification which is laborious, is useful to provide a quick impression of possible system behaviors. It is shown how existing (continuous) control models, like those constructed using software packages like MatLab, can be incorporated in an ASTRAL specification thus leading to a hybrid specification containing both continuous and discrete subsystems. This hybrid style of specification is illustrated by the example of a robot control system. The specification language and some aspects of control theory are discussed in the introduction. In the second section the example specification concerning robot control and incorporation of continuous system models is discussed. Simulation of the specification is addressed in the third section. The final section presents conclusions and suggestions for future work.