Due to the requirement for future production systems to guarantee a high degree of flexibility and changeability in order to meet the demand for customized mass-produced products, the established process sequence-oriented, highly productive manufacturing systems will evolve into physically networked systems. Autonomous and mobile transport robots, which are developing from the familiar automated guided vehicles (AGVs) and service-based mobile robotics, are seen in science and industry as technical enablers for an agile material flow between the resources in a production network.

Holistic intralogistics value stream solution required
Current solutions and approaches to mobile intralogistics systems are driven by the automation and autonomy approach, which enables the individual vehicle or specific system to independently generate a model of its environment. However, this has weaknesses due to the limited range of the vehicle sensors and depicts the environmental conditions at a specific point in time. The vehicles' route planning is therefore based on an outdated model of the world. This approach of autonomy and automation of the individual system also results in a conceptual weakness of the currently available solutions with regard to future requirements. The vehicles are designed for specific, pre-defined use cases and the system's capabilities are therefore limited to these restrictions. The conversion of the sensor data into the digital world model is therefore not transferable to other fields of application without an application or usable for different vehicle types. Transport orders are assigned to the individual entities via a master control system or within a proprietary distribution mechanism. The established approaches therefore represent isolated solutions that do not address a holistic intralogistics value stream solution and only partially meet the requirement for future production systems to form a flexible and changeable intralogistics production network.

Standardized platform with independent services
The solution approach of the research work at FAPS is therefore based on a standardized service platform in which the workspace is digitized and the routes and paths of the transport vehicles are planned. The central feature of this distributed architecture is that the algorithms for fulfilling the necessary individual tasks are divided into independent services. These can be divided into three main groups: the services for workspace recording, the vehicle services and the central fleet services. In addition, the system design follows the principle of reducing data exchange between the individual instances to a minimum and always triggering them as required. The system allows the number of computing units on which the algorithms are implemented to be freely selected, thus enabling the system to be adapted to the specific application. Furthermore, the research approach is virtually unlimited in terms of the area of the workspace and the number of transport robots used. To ensure this, the researched architecture provides for the necessary services to be distributed to the individual systems, such as infrastructure sensors or vehicles. However, the company-internal and cross-vehicle intralogistics services are mapped by a central level. Due to the defined communication structure between these levels, it is possible for both proprietary AGVs and highly autonomous individual vehicles to obtain the information they need in order to increase their efficiency in route and path planning.

Cross-platform transport order allocation
The second elementary component of the service level is also the cross-platform agent-based transport order allocation in the form of an IES. The innovative approach of the architecture is the generic description of the properties of mobile transport entities in order to reduce the application effort of the vehicle software to a minimum. This approach creates a clear interface between the negotiating parties, decoupling the agent's decision-making logic and strategy from the physical platform. This results in a uniform software architecture for intralogistics applications. Furthermore, the decision to dispatch a transport order is made by a transport order agent whose behavior is derived from the company or system objectives. As a result, in contrast to proprietary stand-alone solutions, the focus is on the objective of the respective order when it is placed.

M. Scholz/J. Franke/pb

Chair of Manufacturing Automation and Production Systems (FAPS) at Friedrich-Alexander-Universität Erlangen-Nürnberg © FAPS

Briefly explained: The FAPS
The Chair of Factory Automation and Production Systems (FAPS) at Friedrich-Alexander-Universität Erlangen-Nürnberg conducts research in numerous areas related to robotics. Under the direction of Prof. Dr.-Ing. Jörg Franke, the FAPS currently employs around 100 people at two locations in a total of six different research areas: Biomechatronics, Efficient Systems, Electronics Production, Electrical Engineering, On-board Networks and Home Automation. Various hardware systems and demonstrators from the Efficient Systems research area are aimed at students and companies. FAPS sees itself as a system integrator for innovative mechatronic solutions, which are researched, developed and holistically optimized through interdisciplinary collaboration between the technology fields at the chair and in cooperation with partners. www.faps.fau.de

Scientific Society for Assembly, Handling and Industrial Robotics (MHI e.V.) © MHI e.V.

Briefly explained: The MHI e.V.
The Wissenschaftliche Gesellschaft für Montage, Handhabung und Industrierobotik e.V. (MHI e.V.) is a network of renowned university professors - institute directors and chair holders - from German-speaking countries. The members conduct both fundamental and application-oriented research on a wide range of current topics in the fields of assembly, handling and industrial robotics. Further information on the society, its members and activities: www.wgmhi.de.