Just a short video testing out the newly mounted slip ring. No power is being routed yet, but I wanted to see how it worked in place and if there was any pulling on the cable.

I really am building honest and Artoo is back on the workbench.

I’ve revised my battery charging system and in the process of making a new harness for the larger batteries. I’m also reworking my fuse system, so basically everything had to come out. This may look like a mess, but I know where everything goes back honest!

The new battery harness is designed it in such a way that I can mix my old 7ah batteries  and the newer 18ah. I added a little arm that folds out and holds the smaller battery when needed.

Here it is with mixed 18ah and 7ah batteries in place

Arm out of the way and two 18ah batteries this time

Tonite I’m hoping to finish up the re-wiring.

I cut the hole for the slip ring tonight.

Started off by marking the center lines and then using a hole cutter to score the 7/8″ outline where the slip ring body would sit.

I then marked off and drilled holes where the slot would go for the cable plug to pass through

I used a Dremel and a hand saw to join the holes up

You can still just see the outline of the circle I’d marked

I then took a file and made the small circle notches either side of the slot to accommodate the slip ring

Testing that ring slip ring fit and that the plug will pass through

Top view of the slip ring secured in place

Now to solder up the connectors

I started work on my test slip ring tonight and hope to get it installed in the next few days and report back on a new group order.

The sample slip ring has eighteen 2A circuits and I plan on grouping together 6 or 8 for the +/- 12VDC uplink to the dome, leaving ten circuits for PWM/servo signals. To save on circuits I’m not planning on routing the +/- 5VDC from each of the PWM pairs through the slip ring. As a result each RC channel will require just one wire allocated on the slip ring. I’ll just tap of the 12VDC in the dome and re-create a separate 5VDC supply for the servos.

Out of the box the slip ring wires are loose and really needed protecting.

I bought some braided expandable nylon wire wrap from a local surplus electronics store for less than a dollar.

I wrapped the ends in electrical tape to hold things in place.

Now that I have the wire wrap in place I can start soldering the wires to the connectors.

Here’s an overview video on how I plan to implement the wiring

We finally got some t-shirts made for the local builders

It’s funny, I’ve been working on the new astromech.net website and DroidWiki all week and today used it myself for the first time to look something up.

Sadly I came up blank, but I don’t think it’s the fault of the wiki, but our part naming standards. I don’t think the blue surround that goes around the front vent surrounds has an official name. It’s kinda weird calling it the surrounds surround, but that’s what it is 🙂

My droids skins are removable, and the vents are attached to the inner-frame somewhat permanently. Getting the skins on and off with the blue surround permanently attached to the skins would be tricky, so I decided to kept the blue piece separate and use some magnets to hold it in place. I’m sure I saw the idea on someone else’s website, so I can’t take credit for it.

I carefully marked the optimum spot and glued the magnets on with epoxy

Using some tin snips I put some thin steel and made little tabs that would attached to the skins and allow the magnets to hold on

I attached them to the skins using CA glue

Here you can see the tabs just poking around the vent

And the blue surround in place

It’s not a perfect solution, and I’m a little worried it may pull off to easy. The tabs are also made from pretty thin steel, so the magnets don’t have a lot to attract to. At some point I’ll probably go back and add some thicker steel behind each to help the magnets grip better.

I could trim the surround a little and glue it permanently to the skins, but getting the skins on is hard enough and I’m not sure I want to take too remove that much material and like the tight fit.

Summary of work and posts for March 2008

• Leg/Ankle Screw Update
• Attaching Battery Harnesses
• Slip Rings
• Attaching Battery Boxes – Here’s a quick run down on how I attached the battery boxes to the feet.
• RoboGames 2007
• Mounting the Side Vents
• Side Panels – It’s funny, the side panels are one of the few things you’ll not see discussed. Here’s my method of mounting side panels to my aluminum frame and skins.
• Mega RSS Feed for Builders Blog
• Easter Get Together
• Revised Battery System
• Charging Jack Photos
• Interior Light
• Circuit Building 101
• Battery Power Issue Resolved
• WonderCon Photo

I wanted to report that the new method of attaching the JAG legs and ankles worked. I didn’t have any problem with screws working loose while at WonderCon, unlike at C4, where I had to constantly tighten them up – and had two screws sheer on me.

Back in December of last year I’d decided to use pan head screws with a combination of fender and lock washers , instead of the recommended countersunk machine screws.

They’re do stand out a little but, but once I’d painted them up nobody really noticed them.

Related Posts:

• Finishing Battery Boxes and Feet