A tufting machine embroiders a backing material through the interaction of needle, looper and phase. In many cases, adjustment is still carried out using eccentrics and levers, which are changed in order to set the stroke, offset and phase. The correlation between eccentric or lever position and tool parameters is not recorded, so that the setting process depends to a large extent on the experience of the machine operator.
This is where T-EXDIZ comes into play. Sensors record the condition of the tufting machine quantitatively and mirror this to an Experimental Digital Twin (EDZ). The EDZ enables the user to try out and compare different settings and can optimize the parameters automatically. In addition, it assists the user in transferring the settings from the simulation to the real machine by providing intuitive instructions.
The IGF project “Development of an Experimental Digital Twin for the Analysis and Automated Adaptation of Textile Manufacturing Processes Using Tufting Technology as an Example (T-EXDIZ)” 21166 N of the Research Association Forschungskuratorium Textil e.V., Reinhardtstraße 14-16, 10117 Berlin was funded by the German Federal Ministry of Economics and Climate Protection via the AiF as part of the program for the promotion of joint industrial research and development (IGF) based on a resolution of the German Bundestag.
Results
The movement curves of the tools, which are decisive for the tufting process, were made measurable with displacement sensors. Furthermore, the main shaft was equipped with an incremental encoder so that it could act as a reference variable for the overall system. Based on the design data of the tufting machine, a simulation model was developed that allows the motion sequence of the tools to be realistically predicted. In addition, an interface was installed with which sensor data can be read out, stored and evaluated. With the aid of this data, it is possible to evaluate the machine timing settings on the basis of data and adjust them if necessary. Previously, this required the subjective visual assessment of the machine operator. This was neither quantified, measured nor reproducible.
The combination of this work in the Experimental Digital Twin (EDZ) enables the metrological recording of mold movements, provides assistance for setting up the tufting machine and makes settings reproducible. It provides a simulation of the real machine, which is capable of representing the settings one-to-one and offers angles of view of machine parts that are not possible in reality due to, for example, the machine body. Furthermore, it is possible to either adjust settings manually in the EDZ operating panel and display the effects in a simulated manner, or to have the EDZ calculate new optimal parameter sets. These can then be transferred to the real twin, the real tufting machine, with the aid of the setup wizard.
The final report on the project is available on request.
