This past weekend the Vex World Championships were held at the Dallas Convention Center and I brought my R2D2 there to have fun and inspire some other robot builders from around the world. While I was there I got to meet Grant Imahara who worked on R2D2 in Episode 2 and 3 he also hosts a show on the Discovery Channel called Mythbusters. Here is a picture of me, R2, Grant and the boy scouts. I didn’t get to talk very long but talked to him about my Battlebot called Snuggabot, he had a Battlebot called Deadblow. I also briefly showed him my iPhone controlled sounds and got him to sign my R2 dome.
It’s been a while since my last update because the skins have been going slow. It’s a lot of taking things apart and putting them back together again.
I finally have something worth sharing. I have been thinking of how to make R2′s dome position controlled. Up until now it has been speed controlled. Why bother you ask?
- I have a camera in the dome that I want to be able to aim while I am remotely monitoring it (via iPhone of course)
- To make R2 seem more lifelike by aiming his eyeline in a certain direction
- To make remote controlling it simpler
Here is a quick video I put together:
The position of the dome is monitored through the softpot resistor. I had to make a small custom plate out of 1/16″ lexan that is the outline of the softpot with tabs on the side. The softpot is stuck to lexan and the lexan is screwed to the top COM8 frame ring. I drilled and tapped a hole in the dome plate so the wiper touches the ring part of the softpot.
Here are a couple pictures of the position feedback. In the first picture you can just barely see the wiper white tip touching the softpot.
In this picture you can see the tan softpot ring and wires hanging off the middle of the top frame ring.
The wiring is pretty simple but the software to configure the JRK 12V12 motor controller is pretty extensive.
You may notice the dome seems a bit sluggish. This is due to a few reasons.
- The dome slips when changing directions due to the o-ring slipping on the Rockler bearing.
- I have not optimized the setup of the motor controller yet. I need to tune the system to optimize the performance a bit.
- The motor controller is not turned up to full power yet (450/600). I wanted to play it safe at first and avoid burning it out.
I took my R2 to the Northpark mall and it went great. Everyone took lots of pictures. It was hard to move 2 feet without someone stopping for a picture. I also stopped by the Apple store and showed them the iPhone remote control and viewing and they loved it. Vader was also at the puzzle store so we got a picture.
I finally got some skin on R2. I still need to modify some of the cutouts at the bottom to fit the octagon port, power coupler, as well as trim the back for the pocket vent, and trim the cutouts for the utility arms so they can open, but its looking a lot better already.
This week we brought our R2D2 to several places. The Kidd Kraddick in the morning show, to show Kidd to see if they would be interested in us bringing R2D2 to the send off of the families to Disneyworld. Big Al, JC and Jenna saw it but not Kidd. Too bad. We also took it to my former employer Multicam who let me use some of their machines to make parts for R2D2. Lastly we brought it to Tommy’s school and the kids loved it. One boy was actually rolling on the floor, laughing. You can see his legs when he is on the floor in one of the photos.
This week I have been bench testing iPhone control of my R2′s sound. Last night I did a quick rewire to integrate the new components and tested the whole system at A-Kon (http://a-kon.com/) and it worked out really well. I’ll post a video later of how the system works and what it looks like but here is a quick description for now.
- cool factor – quite a few people noticed that I was controlling it from the iPhone and their reaction was universally “Wow!” and “Cool!”
- very flexible – I can configure the GUI on the iPhone to do whatever I want
- lots of sounds – Currently I have over 100 sounds acessible on the R2 via the iPhone
- the iPhone battery was only able to last a few hours. If you have a longer venue you would need a backpack battery for the iPhone or a spare iPod touch or something similar. My R2s 2 12 amp hour batteries lasted the whole time – around 3-3.5 hrs without needing a swap out.
- there are quite a few components needed in the R2 to support it, some are bulky like the wifi router, although there are smaller ones available.
Surprisingly there were alot of people there interested in the technology of my R2. Maybe around 50% of the people that talked to me wanted to know the tech that went into it. At an anime convention like A-Kon I would expect most people just like the visual aspect of it. I had one group that were filming a documentary do an interview with me and LOTS of people wanted to take pictures, even though its only about 50% complete with no skins and no body greeblies, although the legs and feet are mostly done. The dome is naked right now too. 1 person complained it was too loud and giving them a headache so I turned it down. Noone else complained.
I didn’t use the iPhone to control the drive motors today because I don’t have the deadman switch/failsafe working right yet so it was a hybrid with a Spektrum controlling the foot and dome motors and the iPhone controlling the sounds.
The iPhone sound system consists of the following parts:
- Linkysys wifi router loaded with ddwrt firmware, although any wifi router work work here
- Make controller with application board, not the newer interface board
- VMusic2 module with flash drive loaded with r2 sounds
- 300 watt stereo amp
- 300 watt speakers
The communication worked like this
iPhone –(wifi)–> wifi router –(ethernet)–> Make controller –(serial)–> Vmusic2 –(stero cable)–> stereo amp –(speaker wire)–> speakers
Now I don’t have skins on mine so I didn’t have any issues with the wifi signal getting through AND it was right next to the 2.4 GHz Spektrum and didn’t have any issues. I have a few ideas on where to put the antennas externally and not have them too visible to get a good signal once I get the skins on.
Now the video, excuse the mess. I threw it together in 1 night to get it ready for A-Kon.
Well 24 hours later R2 is taking his first steps. Note that the worlds largest remote control that I am using in the video is an IFI robotics Isaac16 and is kinda flaky and only temporary. Eventually I will use the iPhone or a Spektrum system to remote control it.
I finally was able to get R2 to stand on his own 3 feet and as an added bonus all 3 feet have the wheels and motors in them. It should be very soon that I have him rolling around under his own power!
Well Spain really has nothing to do with it but it rhymes and I’m a bit frustrated with chain on the Senna drive. It’s been a long time since my last post mostly because I haven’t made much progress and just have been aquiring parts. The one thing I would like to make progress on though it getting my R2 moving and recently I got most of the parts I need to do that so I have had a burst of building activity. I just got a Senna drive that Jerry C. ran so I have been putting it together. I put together on drive outside the foot and it went pretty smoothly. The tough part was getting it into the foot. The tolerances are very tight, so tight that the motor casing needs to be ground down to fit it into the battery boxes. Also chain is very fussy when it comes to proper tension and alignment. Too much tension and the chain binds up. Too little tension and it slops around and may even fall off. On the Senna drive the method of adjusting tension is to loosen some bolts and move things around, but the bolts you need to loosen you can’t even reach while the motor is in place so it’s take the motor off, adjust the tension, put the motor on, check tension, take motor off, readjust tension and so on. Really frustrating and annoying.
Chain an I have a history too. I built a battlebot for Season 4 of the TV show Battlebots and it was chain driven. It worked fine when at home, but when I got to Treasure Island my robot was over the weight limit so I had to swap out some metal parts for plastic ones – the shaft collars. Those plastic ones didn’t work worth beans and slid off the first chance they got, causing the shaft to slide over, chain to come off and the whole thing stop working.
Anyhow, now I am back on the chain gang and its deja vu.
This weekend I was able to get the iPhone to control the R2 sounds using a vmusic2 module from Mouser, speakers from Fry’s electronics and a mini amplifier from David Navone engineering. Like the servo control, using the iPhone, this method uses the same microcontroller and the same communication method via wifi with the OSC protocol, running an free app on the iPhone called mrmr. Taking a cue from Chris James, I added buttons that control banks of sounds for different moods or r2 sound types. I went through the sounds I have and sorted them into categories like chatty, sad, happy, whistle, raz, mad, question, processing, holo(leia), dance(cantina music), and a couple others I can’t recall right now. I wrote some code for the microcontroller so that every time you press the sad button on the iPhone, it will play a random clip from the sad set of sounds. I also setup buttons to play all sounds (the “V3A” command on vmusic2 module), stop playing (“VST”) and switch off random mode, skip to next directory (“VSD”), and a slider widget for volume control (“VSV”). I also added a button to go into random mode where r2 will play a random sound at a random interval, so you don’t have to keep pressing buttons to make some noise.
Next up will be controlling the J.E.D.I display with the iPhone and tying that into sound control.
Another cool thing I will work on is feedback from R2 to the iPhone. I should be able to display messages or status on the iPhone display from r2 when needed say like battery level, error messages, what modes are on/off, and the state of various subsystems.