Volume 71, Issue 2 - Special Issue: Capabilities and skills – towards unequivocal descriptions of what machines can do; Guest Editors: Alexander Fay and Jörg Neidig

In manufacturing, many use cases of Industrie 4.0 require vendor-neutral and machine-interpretable information models to describe, implement and execute resource functions. Such models have been researched under the terms capabilities and skills . Standardization of such models is required, but currently not available. This paper presents a reference model developed jointly by members of various organizations in a working group of the Plattform Industrie 4.0 . This model covers definitions of most important aspects of capabilities and skills. It can be seen as a basis for further standardization efforts.

Automated planning approaches provide robust and efficient methods to automatically find plans for a given problem and a set of possible actions. However, due to the rather high effort required to create planning models, these approaches cannot be used for adaptable manufacturing plants. In this contribution, we present a method to automatically generate a planning problem in the form of PDDL from an existing capability model. This method eliminates the additional effort required to model a planning problem, making planning approaches usable for adaptable manufacturing plants.

The flexibility of production systems is a key factor for Industry 4.0. Capabilities and skills (C&Ss) aim at improving engineering flexibility along the production system life-cycle by decoupling production processes and resources. However, traditional reuse approaches in production systems engineering, such as the VDI 3695, do not yet consider C&Ss. This paper proposes the Capability and Skill Reuse (CSR) framework to define how VDI 3695 activities require adaptation for C&S models. The paper analyzes how the framework can facilitate reuse along the production system life-cycle and identifies open issues for research.

Zusammenfassung Sowohl in der Prozess- als auch in der Fertigungsautomatisierung werden Ansätze gesucht, um neue Funktionalitäten effizient in Anlagen zu integrieren. Mit dem Module Type Package auf der einen und Fähigkeitsmodellen auf der anderen Seite nutzen beide Domänen jedoch inkompatible Modelle. In diesem Beitrag werden ein Vergleich der beiden Modellierungsansätze sowie eine automatisierte Transformation vorgestellt. Diese Transformation erlaubt es, Module Type Packages in ein semantisches Fähigkeitsmodell zu konvertieren. Somit werden die bisher inkompatiblen Modelle zusammengeführt und gemeinsam in Produktionsprozessen nutzbar.

Teams of heterogeneous autonomous robots become increasingly important due to their facilitation of various complex tasks. For such heterogeneous robots, there is currently no consistent way of describing the functions that each robot provides. In the field of manufacturing, capability and skill modeling is considered a promising approach to semantically model functions provided by different machines. This contribution investigates how to apply and extend capability models from manufacturing to the field of autonomous robots and presents an approach for such a capability model.

The necessity for increased flexibility in production and handling of high-variant product families is a strong trend in Industry 4.0 scenarios. A promising approach to achieve this is to replace the rigid programming of the manufacturing management systems by a declarative description of machines and their functionality. This allows for a dynamic allocation of tasks to resources. This paper reports the ongoing work on applying the concept of capabilities and skills to an industrial application example in order to investigate its potential benefits. To apply the abstract concept of capabilities and skills to the production scenario it is implemented using specific technologies. These include Semantic Web ontologies, constraint solving methods and OPC UA for skill invocation and communication.

Cyber-Physical Production Modules (CPPMs) must be described by vendor-independent and machine-readable standardized information models. Standards make CPPMs adaptable and interchangeable at different company levels to enable flexible production. We present an OPC UA information model for CPPMs based on the relevant OPC UA Companion Specifications. Combined with the skill concept, a transport system is controlled in an order-driven production. Additionally, we link different state machines to facilitate utilization functions for mission distribution between transport units.