Quick Motor Controller Update

The motor controller is now being controlled by the Arduino and power is running safely through the new power/relay board. Woot! I'm working on the Safety piece of the throttle control (to keep unlicensed chair drivers from flipping it over or accelerating too harshly). Should have that completed by tomorrow.

The relay board has a booboo in it. The 12V Accessory is supposed to only work when the 24V system is energized. Sadly, I wired it after the main (24V) power switch. The electricity is taking the easiest way to ground, which is NOT through the 12V relay coil. Stupid electrons. @Phillysteak527 I might need some of your professional electronics design expertise to do this the right way. I'm bumping up against the limits of me hobbyist knowledge here.

I'll have to come up with another solution for that part of the power board, but, in the meantime, the stuff that matters is working perfectly!

Almost ready to drive!!

August Heat Means Stickers Don't Stick

OK, so, it turns out the vinyl stickers don't appreciate the Arizona heat as it relates to the interior of my truck. :( Several of the vinyl decals are peeled away from the surface of the control panel and that makes me sad.

I'm looking to actually silkscreen the graphics onto the panel, now. I've always wanted to learn how to do it. I don't want to mess up this beautiful panel, so I'm seeking experts in the field. There's a company in Tempe (good resource alert) called Phoenix Interface Technologies and it looks like they might be a good source to do this properly. I've emailed them some info on the project, so hopefully I can get a solution in place quickly.

In the meantime, I may just rig up what I have and bring the "vehicle" (I use that term very loosely) down to LM without all the fancy effects up and running. The Office Chairiot is still a hoot to drive even if it doesn't have weapons or sounds.

Also, as kind of a fun little historical note, I found the original napkin (literally) design I did for the panel, complete with coffee mug AND bourbon stains:

Control Panel 98% Complete!

Everything on the panel is now in place except for LED indicators and the LCD:

I need to 3D print a bezel for the LCD to mount it nicely. The voltage meters... Sorry, the fuel gauges are a little loose, as well. Probably have to use some strategic adhesive placement for settle those into the panel nicely.

The wiring is pretty clean so far (but not organized into neat bundles, yet):

Every switch and button has a nice two-pin female 0.1" spaced header for easy connection to the "Inputs" shift register daughter board. The C++ class that manages inputs simply shifts the states of all the switches and buttons into a few bytes in the MCU and handles all of the debouncing and everything. The Input object then calls delegate objects when there are actual registered presses. It's very clean and efficient and offloads a lot of work away from the MCU.

Silkscreening the panel would have been ideal, after all is said and done, but the vinyl decals were cheaper and actually look really nice.

The glossy decals against the matte powder coat is actually a cool effect, so I'm quite happy with it.

But, of course the best part of the whole panel is having a Weapons quadrant:

Yes!!! The best offense is a good defense.

It's getting close to being operational again. Can't wait to bring it down to the Labs. She's nearly ready to take spins around the LM grounds!

I'd really like to make the chassis reusable, as in, the chair is only an accessory to the chassis. The chassis will have some kind of receptacle thing or set of points into which attachments can go. The chair, maybe a "wagon" box or even a variation of a chairs can be put onto the chassis.

When the wagon box is on the chassis, the user can control the chassis as an office "mule" with an smartphone or even a simple control box. They could walk along with it while it does the carrying. I've designed the control to be handled simply through a UART in the chassis, so the ridiculous control panel on the Ikea chair is only a device that talks to the chassis over a UART and is not really necessary for control.

The simple serial protocol makes it easy to adapt the control to wireless or to a new and cooler control panel with TWICE the switches and buttons or whatever. The base concept, though, is that this chassis is highly adaptable to whatever the own needs it to do. Today, the silly thing can be easily configured to use just a joystick and ZERO smarts, if you want to keep it simple.

After watching the latest ideas that have been move into the process, I'm actually most interested in taking that Rally Fighter chair and putting it on the chassis. Then we'd have the Rally Fighter Office Chairiot Mark II! Sweet.

So many possibilities.

Home Made Printed Circuit Board Quality

Hey @phillysteak527 (over at Local Motors Projects website), I use the positive photoresist method to make my PCBs and I can get tolerances finer than that photo above without any issues at all. It's super easy. I often run traces between the legs on .1" headers and even on QFN and QSOP packages. Between the silly-sharp quality of my cheap little Samsung B&W laser printer and the photoresist process, the accuracy is amazing. Take a look:

I draw everything in Illustrator, mostly for the enjoyment of hand-routing the traces and also for the ability to make the boards more artsy, otherwise there's no practicality to it. ;) I tend to make the signal traces 0.5 pt wide (a hair more than 6 mil; 0.5 pt is a quick selection in the Path toolbox in Illustrator). I prototype this way because I can draw rapidly in Illustrator, print on paper and dry-fit the parts to make sure they fit, then print on transparency, expose and etch in minutes. No waiting, especially if there are mistakes.

But, if I ever got to the point where a project was viable enough to make multiple boards, I'd most definitely go the OSHPark route. Take this project, for instance... Once this bad boy is back up and running and the boards are doing their jobs well, I'd like to sit down with you and work out the most efficient way to lay all this circuitry out for modularity and, of course, fire and electrical safety. ;) I have a complete system map laid out to make visualizing the modules easier.