Posts Tagged ‘Arduino’

CNC Update 7: Simultaneous 3 Axis Motion

Saturday, April 17th, 2010

It’s been a while since my last CNC update because I have been very busy with work, but I have made a lot of progress and a few steps back.

I was able to get all 3 axises put together and aligned pretty well. The only real problem is that my Z axis stepper is not going to have enough torque and it has too much run out in the stepper motor. but for testing it is fine.

First I wanted to explain how I am coupling my motors to the lead screw, AKA all thread :-)

I took a vacuum TEE that I had and cut the barb off of one end.

Amputated Tee

This was too small to just slide onto the shaft of the stepper so I had to press it on using a C-clamp. This makes for a very tight fit. Then I score the barbs parallel to the shaft to give it teeth that can bite into the rubber tubing to keep it from slipping. I then press a short piece of tubing onto the barb and then onto the leadscrew. If needed you can add a tie wrap to secure the tubing even more. Here is a picture of how I pressed it on the stepper.

Pressing on barb

Here is a video of all 3 Axises running at the same time. I am using my arduino to run this test because I fried my buffer chips in by breakout board! That is fine, I will build something better anyway.

Here is a picture of my Z axis flange nut I built. It is hand filed to a press fit so that I can adjust it to align.

Z Axis Flange Nut

 

I have not put any anti backlash devices on these yet, but I have a design in mind for some.

Ir Ranging added to control delays

Saturday, January 23rd, 2010

I added a couple more lights so you could see the effect better. I still have one output that isn’t being used yet. Also I added a couple of ways to vary the delays in the chase sequence. The first was a Potentiometer, the second was a Sharp Infrared Ranger. I am using the value from the ranger to determine the amount of delay in the chase sequence. You could also take the range value and break it down into windows and turn on individual outputs based on how close you are to the ranger. Here is a video of the Ir setup controling the delay.
Infrared Ranging ACLoads 12 Meg download.
Here are a couple more pictures:

Sharp GP2D12 Ir Ranger

I think I have about 500 of these assemblies that have the 4 output board and an intel 87C51 Processor.

I am not sure how many of the 8 output boards I have but it is in the hundreds as well.

Another note, It is possible to control 220v devices with these boards as well. The 4 outputs are paired so that you can provide a seperate line voltage to each pair. Here is the PDF file for the Triac’s that are used on the board. datasheet