Torque measurement method using air turbine for micro devices

The authors have developed a general-purpose system that can measure very low torques in the order of 10^-7 Nm. The new method proposed here uses wind pressure to apply a load to a turbine attached to the output shaft of the device. It can therefore be used for all rotating micro-devices. The use of wind pressure reduces the loss during measurement, and makes it possible to measure low levels of torque easily by simply attaching the turbine to the device. In the present study, the measuring principle of the new system was verified. In addition, a prototype micromotor 1.6 mm in diameter was fabricated and used to demonstrate that the new system was able to measure torques in the order of 10^-7 Nm while the motor was in operation