PowerUltrasonics ::: consultancy :: sonotrode design :: analysis software

(Now updated with a new link to NASA Telerobotics Program Plan, since the old page has been removed.)

An interesting page about research at MIT to develop a high torque-density solid-state actuator for use in the NASA/JPL Mars Micro Lander manipulator arm. It includes a general explanation of the principles of ultrasonic motors, and some cool animations! Note the use of dynamic and time-averaged ESPI (electronic speckle pattern interferometry) to evaluate the vibration modes.

(Link updated March 2008)

Canon's brief description of their development of ultrasonic motors for use in camera auto-focus lenses. Their explanation of the arrangement of piezoelectric elements is particularly good. There are two sets of elements, offset by a quarter-wavelength, each generating a standing wave. Superimposing the offset standing waves creates a traveling wave that drives the rotor.

(Link updated March 2008)

The AEA Technology Sonocrystallizer (TM) is a new reactor which produces better crystals for the pharmaceutical and bio-tech industries. For more details see the July 2000 newsletter.

(Link updated Jan 2007)

The subject of metal welding seems to attract high-quality articles from equipment suppliers. While not as comprehensive as Stapla's book, this article from AmTech gives a good introduction to the theory and practice of welding metals, aimed particularly at wire-joining applications.

(Link updated August 2004)

Ultrasound in liquids creates cavitation bubbles, which as they collapse can generate immense temperatures and pressures, and brief faint flashes of light - called sonoluminescence. It's a strange phenomenon, not yet fully understood but very reproducible. This article gives a clear account of the equipment required to generate and study sonoluminescence - a surprisingly simple set up suitable for a high-school laboratory.