Let's Make Robots!

TinyG XY - Plotter



A friend of mine and I are working on a project called "TinyG".  This project is a motion control system for stepper motors  (up to 254) at a time.  However we are still early in the code stages.  This leads me to this robot.  We currently are needing to test out our Arc code and its very hard to tell if your arc's are working correctly by watching 2 motors spin.  Since necessity is the mother of all invention here we are.

The TinyG XY Plotter Bot...  At the moment this is a place holder for my notes and build design.   The design is close to being ALPHA.  I do suspect many issues to come up.  In fact I already have to change from aluminum V rails to steel ones.

I do realize that this build is easily moddable to accomodate an third Z axis to make this a full desktop CNC.  I plan on doing this.  But first we need a xy table asap so plotter first then CNC.

I will post more when the build is more mature.

I would love to see any design comments or ideas.  BTW you can see on the Y axis (in other photos) that I have cut out a slot to place in a line of magnets to "close the loop" for an magnetic encoder.  Just like this.  However I have not laser cut a new one to place in the slots yet.

UPDATE:  It moves and draws!.... June 23rd 2010

Here is the latest video of my XY plotter dancing to the tune of the TinyG stepper controller board.  

http://www.flickr.com/photos/rileyporter/4698382646/ - Drawing
http://www.flickr.com/photos/rileyporter/4663212692/ - Just Moving.
If anyone has a robot that they would like to drive via the TinyG Stepper Driver, we are interested in hearing from you.  We soon will be testing the board at a limited capacity.  Drop me an email: riley <nospace> porter [AT} gmail dot c0m


UPDATE:  A bit of a redesign...... June 1st 2010 

So the XY plotter is just about finished.... Last thing needed really is adding the table that the "material" (paper... etc) will write on.  However Alden Hart is going to finish this little bit (as he feverishly straight owns the C coding of TinyG).  But alas no more talk... Pictures... and the Vidz...


Here is the current version of the XY Plotter  (soon to be 3axis CNC):

Here is a video of TinyG (the stepper controller software) running the XY Plotter.







May 13th 2010 UPDATE:

Got the steel channels in place and created the X axis "truck".  Screwed everything together and it all its working pretty nicely.  The only real thing left to do is to create the X and Y captive nut mounts.  I have mounts created for the motors but only missing the mechanical linkage.  

Some new photos:


May 8th 2010

I went ahead and removed the aluminum channels and went with a cold rolled steel L channel.  This is working much better.  However I did have to modify the support inserts to have rounded tips since the insides of the L channel uses rounded edges VS. the clean V 90 degree of the aluminum.  Also to note is the steel channel that is avail able via Lowes / Home depot is very "dirty".  Some of it had some corrosion.  Before I placed this into the plotter / cnc I went ahead and brushed the whole outside with an abrasive wire brush wheel.  Turned out smooth. 





TO BE CLEAR:  This is suppose to be a photo of the encoder and the magnetic strip not the XY plotter. This is an older cnc build that I gave up on.