NovemberAbstract Lots of paper deal with the problems of real time systems development. Some of them propose approaches to be independent of the operating system used for the system deployment. This paper introduces a method for development of real time systems independently of the sensors/Actuators (or simulators services) used. The method is explain through the development of Martian task specification. Since it is a simulator-based development, it is well suitable to explain the method and its benefits during the deployment on the real target or when target sensors/actuators changes occurred.