Background / Motivation

In today’s machine tools, viewing windows are integrated for observing the machining process. These have to meet technical safety requirements, since they are a protective installation between operator and machine interior. Therefore, viewing windows in laser machine tools and in machining operations are associated with very high costs.

For commissioning, operation and maintenance of machine tools, supporting and operating systems are applied besides the visual observation of the machine status through the viewing window. These systems are HMIs (Human Machine Interfaces) for the interaction with the machine (handling, display of machine status, implementing controls, diagnosis), and recently they are Smart Devices, mostly for passive interaction with the machine (status display, diagnosis, remote maintenance) or simulation systems for virtual commissioning of the machine and process validation prior to production (offline collision control, process optimization).


Despite the existing viewing windows, the tool or workpiece cannot be observed during machining, because the view of the machine interior is impaired by cooling lubricant mist, dust and chips. In this case, viewing windows provide only little benefit, in spite of the very high costs.

The used supporting systems and operating systems are mostly applied separately on different hardware and at various times. Thus the potential of these systems is not sufficiently exploited. A merging of these systems would result in a clear additional value, for example, when the operator gets more support with manual processes, which have to be performed in spite of the high degree of automation in modern production. For this reason, engineering companies and users have the need to replace the very expensive viewing windows with little benefit by intelligent ones that allow an observation of the machine interior in spite of dirty machining processes. In order to achieve a better operator support, the viewing window is to be upgraded at the same time by linking HMI, simulation systems and the process more closely and by introducing concepts for intuitive user guidance.

Objective / Solution approach

It is the objective of this research project to replace conventional viewing windows as can be found currently in machine tools by novel, intelligent machine windows. The intelligent machine window should represent a window and, at the same time, a user interface, in order to enable the operator the interaction with the machine. Further, according to the Augmented Reality Principle the machine interior will be extended by computer-generated information produced by value-added services. The mentioned functionalities of the intelligent machine window are found each in one of three information levels – machine interior, value-added services and operation – and they are depicted superimposed. The machine interior is directly visible through a transparent display or camera image or it is depicted by means of a realistic visualization on a conventional display. In case of the latter two visualization methods the reconstruction or visualization is performed in real time, so that the display can be used during the machining process. A perspective view is to be achieved by including head-tracking systems.

Replacing the conventional viewing windows by intelligent machine windows:

  • Use of transparent and opaque screens
  • Cross-fading of the real or visualized machine interior with contextual information through Augmented Reality

Development of a software framework:

  • Manufacturer-independent control connection via OPC UA
  • Visualizing the machine interior by using a realtime computer model or camera images
  • Observation of the interior and 3D reconstruction of workpieces and clamping devices by cameras
  • Integrated machine simulation with material removal and collision detection
  • Provision of value-added services in a plug-in system
  • Control of machine and value-added services directly at the viewing window and via a second screen (e.g. tablet)
  • Examination of novel visualisation systems as, for example, game engines for enhanced reality

Name Thematic priorities
DMG MORI Aktiengesellschaft Milling and turning machines
Institute for Control Engineering of Machine Tools and Manufacturing Units (ISW), University of Stuttgart Project management
Value-added service framework
Realistic visualization
Bosch Rexroth AG Control components
Control concepts
ModuleWorks GmbH Parsing of NC code
Value-added services
TRUMPF GmbH + Co. KG Laser cutting machines
ISG Industrielle Steuerungstechnik GmbH Real-time simulation
High Performance Computing Center Stuttgart (HLRS), University of Stuttgart 3D reconstruction

This project is sponsored by the Federal Ministry of Education and Research under the project number 01IM14003C.

The joint project is supervised by the project management in the German Aerospace Center (DLR).


Aktuelle Bilder des Projektes "iWindow"

1 | weiter