The following photo depicts a vibration testbed that uses a motor, springs and some wood. The purpose of this effort is to make a test bed vibrate the attached kinetic energy harvester at the movement frequency controlled by the motor.
The vibration plane is connected to a stable surface by means of two springs. On the vibrating place is a motor that has a weight attached to it. This weight is fixed towards a side of the motor. This is similar to the approach utilised in mobile phone vibrators except in this case, I want the motor to drive a larger weight.
As the motor drives the weight (rotate the weight), the vibration surface will start moving up and down at a perticular frequency. This is what I want. Inorder to limit other directions of motion, I will made sure the moving platform is 1 degree of freedom. i.e. it can only move up and down.
By doing this, the attached kinetic harvester will also move up and down at the same frequency of the moving surface. This is the whole purpose of this setup; a testbed for my research.
I want to have a frequency ranging approximately from 0.5Hz - 4Hz. My mass may range from 100g to about 600g.
In that case, can someone please propose me a type of motor that I can utilise for this purpose? I think it should be a DC brushless motor. But I am not sure. Could someone please be kind enough to tell me what type of properties my motor must have? Any additional information will be highly useful. Thank you for your time.