@inproceedingsHemsel_Wallaschek_2000, title=State of the art and development trends of ultrasonic linear motors, volume=1, DOI=10.1109/ULTSYM.2000.922635, booktitle=Ultrasonics Symposium, 2000 IEEE, author=Hemsel, Tobias and Wallaschek, Jörg, year=2000, pages=663–666 vol.1