Building Platform

Over the last week, I have been building a platform that would allow the projector to sit onto it and rotate when required to. Here are a few images of what I have come up with so far.

The image below shows the bottom of the platform where the stepping motor is. The stepping motor is attached to the bottom board with 4 machine screws and nuts.

The 4 machine screws are also attached to the bottom metal plate. The metal plates in the centre has bearing balls allowing the plates to rotate. I purchased this from B&Q, it is used to rotate a TV once it is attached to the TV stand. However, because it has a weigh capacity of 150kg I only need it to hold approximately 3.5kg. Therefore, I thought it would work for my purpose.

This is how the top of the platform looks. I have attached another board to the top, this is where the projector will sit on. When using your hand to spin the top board, it has enough friction to spin without using any strength which is very good as the stepping motor I am using is only 12volts.

Because I have the steel plates in the centre of this, the top board is slightly unbalanced. Therefore to overcome this issue, I will be making two inner wooden rings placed around the steel plates in which I will place bearing balls allowing the board to spin with balance.

My idea of the two inner wooden rings are similar to the traditional way of handing making embroidery. I will be creating something similar to the wooden frames and attach them to the bottom board, leaving enough gap between the rings to place the bearing balls. However after speaking to some people, I have been told that this way would cause more friction and whether the 12volt motor will be able to rotate the top platform.

I will be speaking to my tutor about this today, and also test the platform without having the bearing balls attached to the board.