We present both the theoretical analysis and proof-of-principle experimental results of a novel transmission-line microwave interferometer for measurements of plasma electron density. The principle of this technique is the same as conventional microwave interferometers except that the sensing microwave propagates along a transmission-line structure. For this study, the transmission-line is a circular coaxial dielectric waveguide operated at 2.4 GHz. A microwave module consisting of a microwave source and a phase detector has also been developed for detecting the phase of the microwave propagating through the transmission-line. Good agreement of phase measurements between the microwave module and a microwave network analyser has been demonstrated. The electron density measured by the interferometer is also consistent with the results from a Langmuir probe.

In the traditional semi-automatic winding machine winding process, the tension of the enameled copper wire changes greatly, and the cable is inaccurate, and cannot be separated from the manual machine. The emergence of automatic winding machine realizes the automation of winding production, reduces the labor intensity of winding, and greatly improves production efficiency. In order to improve the winding quality of the rectangular coil of the motor, a motor winding automatic winding machine is designed. The kinematics and dynamics analysis of the winding process of the winding machine were carried out. The kinematics of the enamelled copper wire and the working principle of the governing mechanism were studied. The kinematics mathematical model of the enamelled copper wire was simulated. The results show that the designed motor coil automatic winding machine has accurate cable routing and smooth winding process.