Sunday, 12 May 2013

Cube update 2

Work progresses slowly, with a few problems I've had to overcome but I finally have a (nearly) working drive system. The only problem is has is that sometimes the connection to the first drive belt to the motor sometimes comes loose. I'll fix it (somehow...)

This is how I wanted to connect the first drive wheel and it would have hopefully connected to the motor drive which is threaded. Unfortunately, my frame is not allowing the thread to reach out far enough, so I am having to make a connector to join the 2 but this keeps coming loose with the wooden connections. I have ordered a tap & die kit to make a threaded connector, which will hopefully have better strength.

The assembled drive and wheel to lift the main cube. The wooden cube i had made was weighing the mechanism down so I decided to make a card cube instead to reduce the load. 

A close up of the mechanism inside

Here is the working mechanism so far. I discovered that if I change the voltage on my dc power adapter, it can also change the speed so I might play around with that. I have decided to control the whole mechanism  with the coin slot with an arduino. I have been wanting to explore using an arduino for a while and this will give me the opportunity. A friend of mine uses them a lot and will be giving me a tutorial.

Now I need to work out how to lock the cube at the top of the cycle. This will involve me spending a long time watching the mechanism in motion and working things out. 

Sunday, 5 May 2013

Cube update 1

I just found out that the charity event for the cube arts centre ends in December, so I figured I'd better get a move on and finish the model. Here's what I have done recently. 

This was a test to check the size of the wheel to lift the rod for the cube and how far the rod raised. I could do with trimming the circumference a little. This is only a rough circle for testing purposes. 

This was a little jig I made to make sure that all of the pins were the same length. I did it by eye and gently hammered in each pin until I could see it was at the same circumference as the larger paper circle. 

Here is the Cube with the pin wheels attached.  I now needed to make a small pulley to attach to the smaller pin wheel. 

Here is the video of the cube in action, raising and spinning. I now need to find a way to lock it in place when it reaches the top, and then have something lower it down again. 

This is the car windscreen wiper motor I bought. I need to test it to see if it has enough torque to turn the entire mechanism. I have mounted it here and will probably need to add a belt drive to slow the movement down a little. I need to have a belt drive to allow it to reach the other side of the frame where the main rotation will take place.

Back view of the motor

So it's coming together, just a little slower than I like, so I need to move it up a gear. More pics to follow soon (hopefully).