Recording and synchronization of machine and sensor data

Comprehensive real-time information about the machining process is of undeniable importance both in research and in industrial environment due to its significant potential for increasing process understanding and ensuring machining stability. Suitable data analyses enable early detection of defects which opens possibilities of timely failure prevention. In increasingly complex interlinked production systems, potential errors, malfunctions or defects are becoming more and more diverse, which lead to a rapid increase in the necessary information content.

A complete development of causal or data-driven models in modern production conditions requires skillful recording and synchronization of various data around the process and its environment. Particular challenge here is the real-time acquisition of the diverse data from various data sources: In addition to monitoring of processing progress through direct communication with machine controls, a wide variety of sensors collect process and machine-relevant characteristics. During the process, large amounts of disordered data are generated. Data types, rates and architectures depend on the data origin and often differ greatly from one another. In order to generate intelligent high-quality and useful data from Big Data, the next step is the use of intelligent analysis algorithms.

• Predictive quality and stability monitoring of complex machining systems
• Ability to perform comprehensive data analyses
• Basis for real-time process control

Utilization in the field of USP laser material processing

Ultrashort-pulse (USP) laser structuring is characterized by very high spatial precision in the micrometer range on the one hand and very high speeds on the other: The pulses with durations of less than 10 ps are applied onto the surface of the workpiece at a repetition frequency of up to several megahertz and deflected over the workpiece at a speed of up to 10 m/s, where they are precisely modulated synchronously to the processing positions. Due to the resulting rapid changes, real-time data acquisition and synchronization of sensor data is a demanding challenge in USP laser material processing. The surface machining processes already established in the industrial environment sometimes take several days or even weeks. For this reason, it is essential to ensure constant process conditions and the detection of defects or fluctuations during the entire processing time in order to ensure stability in production as well as to accelerate time-consuming parameter studies.

Fraunhofer ILT develops multi-sensor systems for monitoring machine and process stability during USP-laser structuring. Various information regarding the process and its environment is recorded and analyzed. In order to meet the high speed requirements, the process characteristics are recorded at a high data rate of 100 kHz absolutely synchronously to the current processing position. To support this, further information from the machine control and sensors for machine condition monitoring is collected at data rates adapted to the individual information sources and stored centrally. The system is equipped with various hardware and software interfaces and thus supports several communication and real-time interfaces which are common in laboratory and industrial environments. It is therefore scalable and can be used for many applications in laser material processing as well as in other machining processes.