Demonstration of vibration control using a compliant parallel arm mechanism

Abstract

There is still a demand for compact, portable, low-cost laboratory equipment for undergraduate engineering students, since turn-key systems are expensive and require substantial lab space. We propose a novel compliant mechanism demonstrating the fundamentals of vibration control to undergraduate engineering students. The mechanism consists of a translational two-degrees-of-freedom system using initially straight fixed-free flexible beams connected to primary and secondary masses. A linear actuator is connected to the primary mass and two laser displacement sensors are utilized to record displacement of each mass. Primary and secondary mass displacements are controlled by adjusting the forcing frequency while keeping the amplitude constant. All parts of the mechanism are three-dimensional printed to reduce cost. The cost of the device itself is less than $5, and with the actuator and data acquisition the total cost is $1300. The mechanism was demonstrated to 32 undergraduate Machine Dynamics and Vibrations students divided into two course sections. Feedback on the student learning experience was collected using the Student Assessment of Learning Gains survey instrument. Results indicate positive overall feedback, with students highlighting the value of using MATLAB to control the system and analyze results, the connections to real-world applications incorporated into the learning activity, and the hands-on nature of the learning experience.