In order to cause torsional vibration, the very first idea came to us is the eccentric effect. And we designed our first model with an eccentric block on one of the Inertia wheels. But unfortunately, it did not go very well that at the speed of about 1600 rpm, the whole instrument starts to bounce and wobble, and the analysis of the experiment data showed that the torsional vibration only occupied contributed extremely little in this vibrating system.

    And in the second model, in order to achieve both torsional vibration and the stability of the whole system, we use a universal joint to generate the torsional vibrating motion. And it follows:

    Then you can change the frequency of the torsional vibration by altering the rotating speed of the motor, and change the amplitude by altering the included angle.

Idea Originated From:

    Because of the great length of the shaft and the complicated load conditions, torsional vibration happens a lot on the screw shaft on board and it has caused some serious damages and huge economic loss. But, in the lab, it was rarely researched because it is not as easy to simulate a torsional vibration as other forms of vibration. Therefore, Prof. Chen and I decided to design a simple instrument that can cause continuous torsional vibration and easy for us to study the character of the torsional vibration.

Knowledge Related:

• LabView;
• dynamic response analysis;
• Circuit Design; 
• Embedded Development; 

  Pictures: