Usability challenges in the design workflow of reusable PLC software for machine and plant automation

Software development for PLC based systems is changing. In addition to the traditional, procedural programming languages for Programmable Logic Controllers (PLCs) from the IEC 61131-3, increasingly object-oriented elements are used, as defined in the object-oriented extension of IEC 61131-3. This paper discusses observed effects of the change on the usability of design methods for software developers. Subsequently, a model-driven, tool supported approach for automation systems is presented. Finally, an outlook on the next steps for the realization of the underlying concept is given.