Here’s another video from The Force Unleashed launch party in San Francisco featuring my droid.

[Link]

Related:

• Force Unleashed Launch Party

Last Thursday Steve and I where at a the Mini Maker Faire at the Intel Developer Forum in San Francisco.  There were probably close to 30 makers in attendance, ranging from robots and electronics projects to Steampunk musicians.

It was the last night of the show and the party was packed. We got to mingle with some cool people and show off Artoo and a bunch of parts and explain what goes into making your very own droid.

I’m in the computer industry so it was strange to be there as an outsider providing entertainment for the evening. It did allow me to make some obscure jokes about Intel chips that nobody would normally get.

This guy was upset because I didn’t have my transmitter in a bag to hide it from onlookers 🙂

We did a couple of interviews and TV spots, including this one with Wil Harris from ChannelFlip. I’ve been listening to him for years on Twit and it was fun to finally meet him.

Big thanks to the Make team for inviting us to this event – they really do know how to organize a great show.

More photos in the gallery.

I’ve been tardy posting updates this last week – been busy trying to get stuff back together for the new Clone Wars movie.

I finally got my periscope installed and functioning. Here’s a short video of it in action

There’s still some small quirks I need to iron out, but I’m pretty close to being done with it (for now). One of the big issues is that everything has to be align perfectly, and taking the dome on and off isn’t as simple as it used to be. What I’ve quickly realized is that with every gadget I add maintenance goes up exponentially.

I repainted the periscope housing after tweaking the curve at the top to match my dome. While I was at it I clean up some spot that I wasn’t happy with

Right now the dome pie panel velcro’s on top of the periscope, but it’s hard to get it to sit flush with so much spring in the velcro. It also very hard to align things perfectly and to get it to stay put. I’m probably going to use magnets instead or even use the small side screws I added. Right now they’re just for show to mimic the ROTJ periscope.

I’m not convinced that the clear lenses look correct either, it’s hard to tell but I suspect the original had a slight frosting to it.

I really need to document the wiring and micro-controller setup for this, but here’s a few overview shots of the periscope installed and there are more in the gallery.

Right now, up/down is manually controlled by the Futaba transmitter, at some point I’ll probably automate this. I also have a small 08M Picaxe micro-controller dedicated to automatically rotating the periscope when it’s fully extended. In addition I have to route 12VDC from the main dome power board back down to the periscope light circuit. The Picaxe and the small mini-servo that rotates everything runs on 5VDC and just taps off of the power for the lift servo.

There are two small micro switches, the first trigger the micro-controller to start randomly turning the periscope when it reaches the top

The second turns on/off the lights when the periscope is raised/lowered

Related:

• More Periscope Work
• Lift Mech Support Bracket
• New Periscope Lift Mech Prototype
• Periscope Port Detail
• Periscope LEDs and RoboteQ

Spent the last few evenings working on the dome pie panels, and after some tweaking I think I have a setup I’m happy with.

I ended up keeping the extra plate on the inside of the pie panel. It adds some detail and I like the sound the panels makes because of the extra weight. I left the hinges in the default configuration with no tweaks apart from drilling some holes to attach the servos.

I glued the hinges in place using CA glue, which sounds like it may not work so well, but I used the same glue on the hinges on the body and they’ve held up well.

Notice how the hinges are angled slightly to follow the curve of the dome.

I could have just glue the hinges directly to the dome, but I wanted to make the panels removable, so I created a small plate that glues to the dome and then then the hinges are screwed to it.

For the front Holo projector I’d purchased some push rod assemblies to attach the servos, but they were pretty expensive for something so simple, and I thought I could do better – this is what I ended up with.

It’s made up of some very cheap and readily available parts you’ll find at any hardware store. It basically some #4-40 and #6-32 screws in varying lengths, and short length of aluminum tubing that I cut up to make some linkages. I think it cost me less than $4 to make four push rod assemblies.

The long push rod is a #6-32 screw which attaches to the hinges via a piece of the aluminum tube that’s tapped at one end for the screw.

A long #4-40 screw passes through it horizontally to fix it to the hinges.

On the servo end I tap a small section of the tube on each side, and drilled a hole in the middle that allows the long screw to freely pass thru until I lock it on the side.

The servo is currently attached to the dome with some heavy-duty Velcro, which works fine right now, but I know it will eventually fail so I’ll be making a mounting brackets next.

Here’s a short video showing the setup in action

The next step is to wire all 4 servos into a PICAXE processor and tie it all together with some software to trigger sequences from the RF remote.

See Also:

• Dome Pie Panel Control
• Dome Pie Panel Hinge Experiments
• Discussion of my Pie Panel setup on Astromech.net – some really cool suggestions.

I’m really not sure where to start with my RoboGames coverage – the weekend was jammed packed full of interesting people and cool things – like talking with the machinist who worked on the NPC motors many of us use in our droids, to hanging out with the Orb Swarm folks or Grant Imahara from Mythbusters, or getting some inside info from the engineer who maintains the machines that spin our aluminum domes. Artoo even got in on some battle bot action in the arena and lived to tell the tail.

The event is held at Fort Mason in San Francisco each year and attracts thousands of people from all over the world. I was in attendance all 3 days with support from my friend Richard, and Gerard was there on Saturday with his R2.

The games themselves cover everything from the traditional battle bot arena tournaments, to robot soccer and sumo fighting. There are also special categories for art and bar tending robots. Maybe next year I’ll enter Artoo into the latter. In total there were 70 different competitive categories.

Artoo was a big crowd pleaser as usual, and many photos were taken with his admiring fans. My favorite was this one I found on Flickr by inkyhack.

Read the rest of this entry »

Well, I’ve fixed the caster problem after a bit of detective work.

A few of you wrote to ask if the 3″ casters were touching the side of the foot shell, they weren’t but clearance is tight.

To simplify troubleshooting I took the center ankle/foot assemble off Artoo and was able to duplicate the locking wheel on the workbench. It even did it with the foot shell removed.

Turns out it was as simple as some crud in the casters bearing. They’d been siting in my workshop for quite some time, so who knows what had gotten in there. And no matter how careful I was, there’s a good chance I got something in there while I was trimming the caster base plate.

The symptom was when the caster did a quick turn it would freeze and drag, slow turns were fine – but anything rapid would cause the lock.

I got some degreaser and soaked the bearing. I then blasted it with air to try and knock out whatever was causing the problem. Once I was happy the bearing was turning fine I re-applied some bearing grease using a small syringe.

And here’s a short video demonstrating the new casters in action

Only time will tell if the new wheel casters perform better in the field compared to the ominballs.

I made a bit of progress tonight getting the center foot ball casters replaced with regular wheel casters.

One of the issues with using wheel casters is finding one’s that will fit. Many builders opt to use smaller 2″ or sometimes 2.5″ casters, but I really wanted to maximize the size to help with difficult terrain. I was lucky to get some of the magical 3″ casters from the Ace Hardware store down in So Cal with the help of a friend.

At first I thought they weren’t going to fit, so I double checked with Victor to confirm that he and Mike really are using 3 inchers. He assured me that they were and sent me some current photos to prove it, along with a few suggestions and tweaks they used to get them to work.

My plan is that any mods I make will not interfere with me going back and installing the original ball casters – just in case the new one’s do not work. e.g. I’ll be using the same mounting plate but will drill some new mounting holes.

I knew I had to remove some of the lip on the front and back of the JAG center foot shell – which I did with the Dremel and a file.

I also had to remove some of the casters mounting plate to allow it to sit closer to the edge of the foot shell.

It wasn’t important to keep the mounting holes as I’d planned on drilling new one’s to match the original mounting plate used with the ball casters.

Here’s the first real test fitting before any holes were drilled

Like an idiot I forgot to take photos of the new casters bolted into place, but I did shoot this short video showing them in action

As I show in the video, ground clearance is now 1.5″ as opposed to the 1″ I had with the ball casters. But this maybe a good thing as I plan on adding an extra “skirt” at the bottom of the foot shell to mimic the center foot as seen some of the movies.

It was getting late, but I did get the foot mounted and a quick test run highlighted a problem with the rear caster not spinning fully. I’m really not sure why it’s not keeping up with the front. It spins freely when I move it by hand but when I run the droid it seems to stick to one side and drag. If I spin him enough it’ll rights itself and sometimes it does keep up.

Here’s quick shot of it sticking – I was trying to do a right turn when this happened.

I suspect it might be something to do with the fixed angle in the outer feet/legs, using wedges, which should be an easy test to see if it’s the problem.

I also need to add some wedges to the front foot to stop it tipping. With the three original ball casters located in the extreme corners of the foot this rarely happened – but now with the casters closer to the center it tips/drags very easily.

Here’s a collection of video of us at Maker Faire

Skip forward to the 2 minute mark for the interview

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