A development tool combines advantages of a simulation tool with an object-oriented modeling tool, including a real-time mathematical matrix library and an object model. The tool is applicable to any intelligent control system. A composite object group (COG) contains both sampled-data and event-driven capabilities. COGs merge procedural and object-oriented programming, and provide explicit, graphical integration of both types of processing and are fully hierarchical. A control system is built up of object-oriented components, including these types: atomic, interface, data flow and state transition. A finite state machine (FSM) component is built from states, transitions, events and state transition components. Data flow components provide sampled-data capabilities. FSMs provide event-drive capabilities. Each component may include methods and attributes. A COG includes any type of component including COGs, graphical interconnections between components, and is used to graphically build a model of a control system.