Development of a high-speed synchronous micro motor and its application in intravascular imaging

a b s t r a c t In this study, we demonstrate the design, fabrication and characterization of a synchronous micro motor. The micro motor consists of flex print coils and a permanent magnet rotor. The size of the motor is 2.0 mm length and 1.0 mm outer diameter. With 1.0 A effective driving current, the motor can rotate a 0.3 mm mirror at a maximum speed of 3640 revolutions per second. The uniformity and accuracy of the motor was characterized at 50 Hz, 200 Hz and 3200 Hz driving frequencies. The performance improved by increasing the driving frequency, which was represented as better speed uniformity and lower angular error. The torque of the motor was estimated to be 0.25-0.27 N m with 1.0 A current by fitting the measured speed based on the equation of motion. We describe the application of the micro motor as a distal actuator for intravascular imaging. We constructed optical and ultrasonic imaging catheters and show the intravascular images of coronary arteries obtained with these catheters. © 2014 Elsevier B.V. All rights reserved.