For a very long time, i have always wanted to create an XY plotter / engraver for engraving flat sheet, and engraving my own custom PCBs. Sometimes i get all motivated, and do a lot of reading, and try and work out how i want to do it
for a while, i’ve had sitting in my shed, a box of parts that once was an old XY graph, that looked very similar to this photo:
which i borrowed from THIS PAGE
Regrettably, in all my wisdom, it is in many pieces, and is unable to be re-assebled to its original state, so i am going to have to go to a little more trouble and piece together my own control circuitry to make it go.
The Axises are controlled via a DC motor for each axis, and a cabled drive mecanism. Position is known via a potentiometer incorporated into the axis. My plan is to, hopefully, use a picaxe 18 to read the position, and take an input to move the axises to a specific position
The following shot shows the chassis of plotter in its current state. there is a nice thick plate of aluminuim that is the surface, that used to have an electrostatic cling coating on it, which goes over the top of the pullys and everything, to give a nice drawing surface on it.
The next shot shows the bottom of the chassis, showing the potentiometer track that runs along the slide rod for the axis (on the bottom of the shot). There is a similar setup for the other axis. i am not sure how precise i will be able to be with this type of setup, only some experimentation will inform me. i’m guessing, coming from a piece of scientific equiptment, the potentiometer should be pretty good, and it will be a matter of the ADC on the picaxe, and how i choose to drive the motors
So, to come, i will have to work out how i want to interface it to the Picaxe 18x i plan to use to control the plotter, and the actual firmware for the picaxe, and then, actually controlling the plotter from a computer program (well, actually, i guess the computer control will need to be integrated into the hardware and firmware design)
Unfortunatly, the project probably won’t get too far over the next month or so, as i cease doing stuff to try and get ready for an impending house move. hopefully it will not cause too many disruptions though