Finally have all of the connections wired and (more or less) tested. I’ve added LEDs to the running lights and servos (not shown) to control the couplers. Just need to add about 11oz or so to the fuel tank and put it all back together for final testing. I’ve attached a programming cable to the microcontroller board so I can download new builds or tweak the s/w if required. Phew. This has been quite a bit of development. The control widget itself went through many interations (see controlwidgets.com) as did the power board. I’ve settled on the Pololu 18v7 programmed to only give forward motion with a relay switching between forward and backward. Anyhow, soon we will be doing some real world testing.
Got my Aristo RS-3 wired up for an Xbee widget. More computing power in my tiny locomotive than went to the moon. Ha.
Widgets are my own Atmel micro-controller design, more here: controlwidgets.com
Here is my latest stand-alone hand-held-throttle design. It’s based on my control widget thing and I (finally) have it all working.
All the circuits and keyboard are mounted on a 3D printed faceplate with a 3D printed back enclosure. It still needs some structural work, screws to hold the face plate on and I need to mount the power switch too, not sure where that should go.
There is some hard-coded stuff in the handheld software but it does work quite well. I also have a slight design gotcha on my USB interface into this thing but I’ll get that solved soon.
I’m really enjoying my widget PCB design. Simple, cheap, easy bake oven for SOIC, program in C, add an Xbee for wireless real-time control, how cool is that? Here I have one hooked up to a parallax IR motion sensor. With a bit of C code it controls the servo based on the input from the motion sensor. Think railroad crossing signals- that crossing arm that comes dowm and blocks the traffic, right?
Anyhow, great fun and a good project to post over to controlwidgets.com
I’m looking at a $9 retail for board and components. Software will be free and open source. Of course
Getting a bit more physical here, I finally got a nice 3D print of the faceplate that works, this is number three I think. Mechanical design is much more difficult than I thought. Even with a 3D printer, some things just don’t go together like you think they should.
But so far, with some minor tweaks, it all fits.
My 3D printed friend looks over a batch of brains going into the oven this afternoon. A completed one is at his feet and below that is the original prototype. For perspective, he’s 6 ft tall in 1:29 scale.
More info: controlwidgets.com
Boards have arrived, here is the first one fresh out of the toaster oven!
More info on these can be found here:
A more informative diagram: