R2 makes his big debut on the EMMC Pediatrics Floor

Today, after much planning and work, R2 got to go to the Pediatrics floor and entertain the kids!

Due to privacy requirements, I didn't take any pictures of R2 with the kids. Plus, I was too busy driving R2 around!

The kids, parents and staff were all amazed to see a real life R2-D2 in person!



On the technical side of things, I have several things on R2 that I am going to try to improve.

R2 seems to have one NPC motor that is much stronger than the other. I used the RoboteQ software to test and monitor the motors on the laptop. The left motor is much more powerful than the right, so I reduced power to the left one. It still requires a lot of left input to drive straight. Upon tear down and inspection next week, I'll check the foot drives and belt tension on each foot.

The center foot has a shimmy. R2 struggles to straighten the caster wheels inside the center foot. It could be as simple as an axle too tight. We'll have to see and test some more.

Electronically, everything worked very well. The dome lights lost power when the power cable got yanked out. The cable fell between the dome and body while the dome was moving. A better way to route power to the dome , such as using a slip ring, will have to be considered in the future.

Battery power was fine, no issues there. The XBOX Windows gamepad system worked fabulously. It was fun to hand the kids the gamepad and let them trigger R2's sounds.

I had an awesome time bringing smiles to the kids, parents and staff. I had a LOT of great help from a lot of people getting to this point! Thank you all!

R2-D2 maintenance! Locking the ankles and checking the shoulder mounts out

One thing I knew I would have to do at some point was to figure out a way to lock the ankles into place. With the high-torque NPC-2212 motors and the stop and go movement of R2-D2, I was seeing a lot to rocking and swaying between the ankle and feet.

As others have suggested in their build blogs, they have made wedges and drill/tapped/bolted the wedge into place.

I went with the suggestion of Mike Senna and Victor Franco made: cut up some pieces from a plastic cutting board. Its thick, has a bit of flex to it and inexpensive. I found a $2.99 cutting board at Lowe's and as ironic as it sounds, cut it up.

Using some scrap paper, I made some simple templates to roughly cut out of the plastic.



Now cutting plastic with a Dremel is...well...a real messy experience. However, its the most effective way to zip it piece out, check for fit, file down a bit, check for fit and repear til you are please with the fit.

They aren't perfect but they do the job. After installing these and driving R2 around, there is a huge difference. After doing the test drive, I wanted to check so see how the shoulder assembly was holding up. I was curious how loose the nylon-insert nuts had become from all the rocking around.

Thus it was take-apart time to check the shoulders. I did find that they were a bit loose and while not dangerously so, I opted to replace the nylon-insert nuts and also added a flat washer for good measure. With the dome plate removed and the dome off, I checked for anything else that might require some snugging up. Everything looked alright, so now the batteries are all topping off their charges for this week's events.

R2's sound system

Getting R2's sound sysem rolling has been an interesting process.

Initially I wanted to do what many other builders have done, using a programmable sound device with an FM remote that could play specific sounds. The problem I had with this was the cost of the hardware and the limited number of sounds it could play.

To get by on Halloween, I borrowed my friend's Netbook for sounds. A Netbook is a mini-version of a laptop, with a 10" inch screen. It has wireless networking so I was able to command sounds to play from my laptop on Halloween.

I ran some ideas by my friend Randy since he is a talented, hobby programmer (he would ask I emphasize HOBBY). We've had some great brainstorming sessions and came up with a computer program that uses a wireless conrol pad, in this case a Windows wireless XBOX controller, to play sounds. As we go along, we keep adding and refining things (it may be completely different after I publish this entry!).

At this point, we have divided the sounds into 3 buttons. "Happy", "Chatty" and "Sad/Scared" which each have their own folders and sounds in each. When one of the buttons is hit, it randomly plays one from that sound category. But then we added a STOP button to cease the sounds. Then, we made an "Idle" mode, so that sounds in the "Idle" category would play a random sound every 45 seconds.

I have an 18 minute high-quality sound clip of all of the original R2 sounds. After hunting around Download.Com for a few hours, I finally found a utility that would allow me to cut up the sound file based on pauses so many seconds long. After setting the program to look for pauses that were less than a second, I suddenly had a lot of sound files to work with!

Originally, from the various downloads offered, I had about 30 R2-D2 sounds of good quality. Now I have over 240 in superb quality! (It took a LONG time to categorize those sounds!)

The setup has a few cons...the netbook has a small hard drive, only 4gb. Despite all efforts, this thign is always low on space thanks to Windows Update! I have had to do a lot of system tweaking and it seems like a daily battle to optimize the system setup. We have some ideas to address the issues...but its just a test setup anyways. The 1.5 watt speakers are "ok" but something more powerful, with a modest power requirement, would be better.

Here's how the test setup looks...



....close up...

More soon!

R2-D2 is moving around nicely!

Here's an new video clip showing R2 moving around with lights, head movement and such. Next up is getting the sound working, which my friend Randy Hunt is working on.....more on that another time!

The grand reveal...R2-D2 amazes the kids for Halloween

The big night arrived...Halloween! The day I worked towards to have R2-D2 functional and ready to show off to the Trick Or Treaters.

Earlier in the day I was able to borrow a co-worker's minivan. I really didn't want to have to remove R2's legs to get him out of the house, so I was able to get some help from my friend Roger to lug him out. Minus the dome, R2 fit perfectly inside.

Once I had R2 at my parent's place, which gets a TON more trick or treaters than my house does, I put everything back together.

For sounds I borrowed my friend's Netbook, which is essentially a mini-laptop. I wrote a batch file that would randomly play an R2 sound and used VNC to connect to that Netbook from my laptop. Due to the limited resources of the Netbook, I eventually resorted to launching sounds manually....i.e. the good ole double-click...and it worked great! I sat several feet away from the action with the Spektrum transmitter and laptop while R2-D2 beeped, turned his head and greeted the kids.


....and the kids...

...loved R2-D2 !

We ran out of candy at 7:45pm and lost track of how many times we jammed traffic on the street! R2 was covered in fingerprints but held up fine! Here's me and R2 after a thorough wipe down/cleaning...