The first phase of the Faguy academic internship was carried out from February 01st to June 30 th 2016 at CURES in order to prepare its final dissertation. The second phase took place from September 5th to December 23rd in Neuchâtel and concerned the "Integrated Selector System for Industrial Knitting Machine"
The aim of the work was to simplify the sensor system of a compact industrial compact knitting machine enabling the knitting of a wide variety of structures and shapes of the STEIGER company in order to save the energy consumed by said Sensors, reduce costs and also increase the reliability of the entire machine. The new solution envisaged aims at optimizing the selection head in order to increase speed and energy, but above all to eliminate the position sensors and to replace their function by "Sensorless" or "Self-sensing" methods which consist in using l The actuator itself as a sensor.
In order to carry out its mission, Faguy first carried out a complete analysis of the operation of the selector. Consequently, he proceeded to study his frequency response. Study after which the trainee obtained the frequency ranges useful for the evaluation of the sensorless methods of injection of high-frequency sinusoidal signal and of variation of the electrical time constant during a second experimental phase. From this evaluation, the sensorless technique of high-frequency sinusoidal signal injection proved to be the most suitable because it enabled identification of the keys that were actuated or not by observing the variations of impedance and the phase. Finally, Faguy proposed a sensorless sensor-detection system exploiting the variations of impedance at the passage of the keys and implementing a Kalman filter as well as the structure of the associated electronic circuit.