Monday  |  Salon 10  |  05:10 PM–05:30 PM

#12803, An Open-source Automatic Modal Hammer Suitable for Studying Nonlinear Dynamical Systems

Although automatic impact hammers are often used in dynamics and vibration research, they are seldom if ever used in resource-constrained environments such as undergraduate labs or in emerging nations. The cost of a commercially available automatic modal hammer, which typically costs more than USD 10,000, is the primary reason for the technology's limited adoption. An inexpensive, automatic modal hammer could thus be useful in educational labs for studying dynamical systems. The goal of this research is to develop a low-cost, repeatable, and scalable automatic modal hammer. The study's main goal is to develop and test an open-source modal hammer for studying dynamical systems, including the ones which are strongly nonlinear. A standard modal hammer is mounted on the shaft of a stepper motor, with an encoder controlled by a hybrid servo drive and a microcontroller. The combination of the motor, servo drive, and encoder allows for micro-stepping and precise control of the motor shaft, and thus the motion of the modal hammer. The stepper motors used in this hammer are similar to those found in small 3D printers and CNC machines and are thus widely available and inexpensive. A model airplane wing with a non-smooth nonlinear vibration absorber is used to demonstrate the automatic hammer's functionality.

Aryan Singh   University of Nebraska, Lincoln
Keegan Moore   University of Nebraska, Lincoln