Related Posts:

• WonderCon 2008 Show Report

I’ve been busy most evenings this month getting ready for WonderCon, but thought I’d stop and post this new addition which I’ve been working on and off for a while now.

I’ve expanded my battery charging port to include some LEDs. The flashing pattern is based on the scene in ESB where Luke and Artoo meet Yoda for the first time.

The whole thing is driven by a 18X Picaxe board with some custom code. I’d originally planned on using some simple timer IC’s, but thought this would be a good project to experiment with Picaxe.

I’ve tried to capture the LED sequence the best I could, but it’s only shown straight on for 10 seconds, and even then it’s obscured by the door some of the time.

To get to this point I had to create a new acrylic mounting plate. I still need to wire in the new charging circuit Bob helped me redesign, but this was the first step in the process.

I went through several iterations and prototypes to get it to fit and work around the Robart hinges. Hence the slots on the left hand side.

I’m hoping to fix it to the 12V charging socket and use it to mount to the metal bracket I made a few weeks ago as part of the original charging circuit.

It’s also been a steep learning curve the as I’ve not really done any major thinking about complicated electronics in a very long time.

I’ll try and post more details in a few weeks, but here’s the completed circuit after a few late nights. I may switch to a smaller Picaxe, like the 08M, as the 18X is a little bit of an overkill for this project. But the price is negotiable in the grand scheme of building a droid. I’d have to guess the whole circuit costs less $35, but in the process I had to buy a bunch of stuff to figure out how to get it to work.

Here’s a a close up of the LED matrix connected to the PICAXE board.

I also had to create a voltage regulator circuit to power everything directly from the batteries as the main power distribution board will be isolated/turned off when the batteries are charging – and the whole point is for R2 to show some bling while he’s charging right?

I ended up using a LM7805 which will step down the 12V supply to the require 5V.

When I get a chance, the plan is to eventually make the LED’s display the current battery voltage when I press a button as the Picaxe 18X has a built in voltage reader.

This is short video of Gary Weaver’s aluminum R2 that inspired so many of to start building. Someone posted the videos on the Builders Group today, and I thought I’d pulled together this little montage.

It may not seem that impressive today as droids are a dim a dozen, but this was built many years ago and he helped pioneered the way for all us aluminum junkies. I can clearly remember Gary posting regular updates on the Replica Prop Forum and thinking to myself that I’d never have the patients, the skils or the money to pull something like that off 🙂

Here’s a great video by Mike Senna on how to pick and fit castors for your center foot.

I’m currently using omni-balls, but I may switch them out soon.

See also

• Proctor Glove Wheel Casters

I vaguley remember doing a few interviews at C4, but never thought I’d see any of them. But today I found one on Youtube.

Here’s my latest short video tutorial, this time it’s on cutting your inner dome holes.

This was one of the first things I worked on a year ago, and I’ve finally mastered video editing enough to put something like this together.

Enjoy.

Related Posts:

• First Dome Hole Cut

Last week I made a new aluminum dome drive mech to replace the Daren Murrer’s HDPE version I’d been using. There wasn’t much wrong with the one I had to start with, but I gotten it in my head I wanted to try making one myself from aluminum to go with my new dome motor.

The one I created is a combination of Daren’s and the original Atomic Pickle design design. Here’s a photo of my original HDPE mechanism on my aluminum frame.

I used some 1/4″ scrap aluminum that already had a few holes in it, so I had to work around them using the original bracket as the template.

I don’t have a mill at home so everything would have to be either cut on the band saw, Dremeled, drilled or worked by hand tools like a file.

I rough cut the piece on the band saw and drilled the initial holes

The long hole in the center was greater from three smaller holes I’d drilled and filed away to create one big hole.

One issue I knew I would have was making the center hole/cut-out large enough to accommodate the approximate 1″ wide lip/step on on the motor. Also note how the drive shaft is off center due to the gear box.

At first I thought I could file away enough material but it would be slow going. I could also have bought a $40 1″ drill bit but I had another idea. My Dremel has a router attachment that could create a lip on the long slot that I’d created.

I forgot to take photos of the next few steps, but the rest of the mechanism that bolts to the frame is pretty simple, and just two blocks with a few holes in them. I made the main support piece a litte wider than on the Atomic Pickle design as I wanted to add extra support to the main bracket that holds the motor.

Here it is installed in the frame. Note, in some of these photos the motor is flipped the wrong way and the shaft should be toward the center of the frame.

At the pivot point I drilled and installed a bearing like the original Atomic Pickle design, but on hindsight I probably could have just stuck with Daren’s idea of just having a regular hole with a bolt through it.

Here’s the motor position correctly in the bracket

Overall I’m happy with how it came out and given a template and basic tools anyone could make one at home.

Here’s a short video of the new mechanism in action

Happy New Year everyone. Slow day today. Doing some research for my door panels and servos needed.

Been chatting back and forth with Chris Grootjans in Belgium on how he went about it. Here’s a cool video of his setup using micro servos directly attached to the Robart Hinges. I really like the solution because it doesn’t need any extra push rods etc and everything is more self contained.

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Full details of Chris’ setup can be found here.

Right now I’m toying with the idea of just ordering a few mini servos from ebay. Typical cost is $20 shipped for 4 vs buying them domestically where one would cost at least that much. Size is around 22mm x 27mm x 11mm, but I’ve seen them as small as 20x17x9.

Update: I never did receive my servos from china, so buyer beware, the good news PayPal refunded my money.