Looking to adopt a more general methodology, PLCopen is calling for participation in a new initiative on coding guidelines. Although there are coding guidelines for many programming languages, these are nearly non-existent for the important area of industrial control, including IEC 61131-3 and its PLCopen extensions.
Nevertheless, software is becoming more and more important in industrial environments, software projects are getting bigger, and the costs of errors continue to rise. Software nowadays absorbs half of the initial project costs, and 40-80 percent of that deals with maintenance over the lifecycle costs of the software.
Dealing with the complexity of larger programs requires modern software development processes supporting a structured approach. Also, we need to increase the efficiency in coding via reuse of pre-defined functionalities and to help to better understand the program over the lifecycle.
Also, optimizing production lines, through overall equipment effectiveness (OEE) or manufacturing execution systems (MES), requires getting more information out of the controllers—information that, via harmonized naming conventions, can be made accessible “out of the box.” Creating more efficiency in production means more information from the control level and transparent communication across the levels.
Many suppliers have to deal with these issues in their training programs, in addition to universities and technical schools. And not always sufficient attention is given to these issues, pushing the costs in later stages of the lifecycle.
Parallel to this is the growing market of automated testing & validation (AT&V) to help ensure the software quality, which becomes more and more a pre-requisite, and not only in safety-related environments.
Combined, these are reasons that the organization PLCopen now wants to combine forces for a more general adoptable methodology. There are differences between coding conventions for languages and those for projects. Examples outside the industrial environment are for projects GNU, Mozilla or GNAT, and those dedicated to programming languages like Java, C++ and Ada, or newer standards and frameworks like ISO 26262, AUTOSAR and DO-178C and MISRA C. For both phases, PLCopen tries to use as much as possible available specifications and initiatives.
PLCopen will hold a kick-off meeting June 5 in Frankfurt, Germany.
