Development of clinical detection ultra-small ultrasonic motor

Recently, a research team at the Toyohashi University of Science and Technology in Japan successfully developed an ultra-small ultrasonic motor with a volume of only 1 cubic millimeter. In the future, this ultra-small ultrasonic motor will be widely used in medical endoscopes, cameras, and mobile phone terminals, in addition to medical catheter surgery.

Recently, a research team at the Toyohashi University of Science and Technology in Japan successfully developed an ultra-small ultrasonic motor with a volume of only 1 cubic millimeter. The volume of the new motor is less than 1/40 of that of the existing smallest motor, enabling both rotary and axial movement. This ultra-small ultrasonic motor can be used for the examination and treatment of cerebrovascular diseases. Based on further improvement of performance and clinical experiments, it is expected to be practical after 3 years.

The driving part of the ultra-small ultrasonic motor is surrounded by an alloy as a stator, and the stator is a porous structure, which is conducive to the transmission of mechanical forces. Piezoelectric devices are affixed to both sides of the stator. Piezoelectric devices can be flexibly moved by using two kinds of AC voltages. This telescopic motion translates into a vibration of the stator forming an axial force with a maximum axial force of approximately 30 microNewtons ([mu]N), which can be controlled by varying the voltage. The maximum torque of the micromotor at 900 rpm is 10.5 nanonewton meters (nNm). Due to the simple structure of the micromotor, the manufacturing cost at mass production will be greatly reduced.

Nowadays, patients with heart and brain infarction caused by thrombosis in the heart and brain blood vessels are often examined and treated using a catheter insertion method. Since the heart vessels are usually thick and the cerebrovascular blood vessels are fine, it may be necessary to use this ultra-small motor for catheter treatment of cerebrovascular diseases.

At present, the research team is improving the design and production of ultra-small ultrasonic motors, trying to achieve a rotational torque of 0.1 microNewton meters (μNm) and an axial force of 0.3 microNewtons (μN). In the future, this ultra-small ultrasonic motor will be widely used in medical endoscopes, cameras, and mobile phone terminals, in addition to medical catheter surgery.