Reusable industrial control systems

Industrial control hardware may be reused for several purposes. The same industrial PC type may control the drives of a portal system, act as a programmable logic controller, or control any other device. Moreover the same piece of hardware may control different device types at the same time in concurrency. In this paper, we discuss four successive software engineering approaches to exploit the possibilities provided by the control hardware: an object-oriented architecture, an architectural pattern, a control framework, and an architectural model for component-based frameworks. Each of these approaches provides means of different levels to structure a system and to reuse concepts, patterns, or real code. All presented approaches are used to build control systems controlling different types of robot arms and other devices. Additionally, in the component-based system a new component has been introduced to enable a network connection of the control system.