The project seeks to improve the performance and accuracy of a specialized electromagnetic actuator developed by Dr. Toshiro Higuchi and Dr. Hiroyuki Nabae at the University of Tokyo. The actuator is capable of performing high precision and high speed movements. However, the actuator also tends to exhibit unwanted vibration when operated, greatly reducing its precision. The goal of the project is to implement a command shaping method to eliminate the unwanted oscillation, improving its precision. Potential benefits include developing a reliable actuator that can improve performance in applications where piezoelectric actuators are currently used. The project will be conducted at Tokyo Institute of Technology during the summer of 2017 under the joint supervision of Dr. Gen Endo and Dr. Nabae.
The project will involve vibration attenuation of electromagnetic linear actuators capable of quick sub-millimeter strokes. In general, electromagnetic linear actuators suffer a loss of thrust force as stroke distance increases due to the gap between the electromagnet and the armature. The actuator developed by Dr. Higuchi and Dr. Nabae utilizes an amplification mechanism that increases the stroke distance while maintaining thrust force for the extent of the movement. However, the actuators are prone to unwanted oscillation with amplitudes of hundreds of micrometers, which results in significant residual error when compared to stroke length. The goal of the project is to implement a command shaping method to improve precision. The command shaping method to be used utilizes a system's natural frequency and damping ratio to find impulses that interact destructively to cancel residual vibration. These impulses are then convolved with the system's original reference command to produce a command that causes no residual vibration. Benefits of this project include developing a reliable actuator capable of accurately performing high resolution movements without the drawback of a significant loss of thrust force.
This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.
