Drawbot update, and ShapeOko's first real work

Last night I spent some time in SketchUp designing a pen carrier for the new drawbot.  This morning I exported all the parts to .dxf, pulled them into CamBam+, generated the gcode, and cut parts on the ShapeOko.  Here's the results.

My New Toy Takes its First Steps

About three weeks ago my wife bought me a really cool gift, and tonight my new ShapeOko CNC mill took made its first moves.  The crappy video is it running the ShapeOko "Hello World" job.

Drawbot software on it's way

To paraphrase "Cool Hand Luke" - what we have here, is the ability to communicate!

In this video the comms board and the pen carrier board are connected up and working for the first time.  The comms board connects to my desktop via USB, and is connected to the pen carrier board via RS-485. When I send a command out the USB, you can see the transmit and receive LEDs flash, then the pen carrier board responds by changing the servo's position.

The protocol the boards are running over the 485 link is dead simple right now, and not capable of multi-drop communication.  So, the next step is to implement a new protocol.  The carrier board also only implements binary servo positions up, and down.  The new protocol will give the ability to send data through the link, so I can control how far up/down the pen is.  With this I'll be able to use brush tip markers, and vary the line thickness drawn by the 'bot.

Two boards built

I've gotten two of the four boards for the drawbot built and sort-of working.  The top one is the controller for the pen carrier.  It will receive commands over the RS-485 bus (through the big black jack) and drive a servo through the 3-pin header.  The six pin header at the top is for in circuit programming the pic16f1823 micro, and the two pin header is for power.

The bottom board is the usb to RS-485 bridge I prototyped.  This version just has some indicator LEDs.  One for power and two more for data reception and transmission.

Now it's time to work on the software to get the two boards to talk back and forth. Oh happy happy joy joy!!

Green Boards Comin Outa Ma Ears

All my Drawbot boards arrived from the fabricator today.  Time to go by a bigger magnifier and get to building!

This is the communications board that converts USB to RS-485.

This is the board for the pen carrier.  It takes RS-485 in, and drives a servo to accomplish the pen up/down.

And this is the winch board.  It takes RS-485 in, and drives a 2 phase bi-polar stepper motor.

Yet Another Particle-Bot Prototype

Here's another Particle-Bot prototype.  This one is a lot closer to how I see the final robot.  Using pager motors without a gearbox really cuts down on the unit cost, but to really be able to evaluate the design I need to build a better chassis.  I'm currently thinking 3D printing would be a good choice.

Two Particle-Bots, and two programmers, two nights work.

Another particle-bot prototype

Well, I couldn't wait to get a real chassis for my new Particle-Bot boards, so in about 20 minutes I put together this prototype - made form really cool purple cardboard.  

Here's a really crappy video of the 'bot programmed for light seaking