Not only that, we can measure it. Here’s a plot of two axes of accelerometer data. This was generated by the Inertial Measurement Unit, talking to the daughterboard, passed through the SPU, then captured by the new logging feature of the mothernode dashboard application.
(Did you know Python has a csv module for saving exactly this kind of data? I just found that and it sure made it easy. Three lines of code, people!)
This data shows me gently turning the IMU from side to side, then waving it around.
Full-court press (or should that be “roll”) this weekend for orb test in the desert next week. Come on down and help! We’ll be at the boxshop getting in the way of the Flaming Lotus Girls.
Well, the boards came yesterday and passed the smoke test (you plug it in and if it doesn’t smoke, it passes). Today I got everything working together: Here’s the daughterboard motor controller, sitting happily on top of mom SPU.
Both are running fine and chatting happily together. That’s a warm fuzzy feeling, right? It sure is for me.
Technical details: the daughterboard contains an Atmega-8 microcontroller and mates with a TS-7260 embedded Linux board from Technologic Systems. The Linux board is the Swarm Processsing Unit, or the SPU as we like to call it. It’s the brains of the system. The daughterboard microcontroller generates motor control signals and reads analog signals from the inertial navigation unit. Petey the Programmer made the prototype version this is based on: thanks Pete!
(local copy)
We came, we rolled (local copy). We blew a fuse, replaced it. We lost a chain. We fixed it. We encountered significant deviations from the spherical, when we jumped the track at the Power Tool Drag Races . (We lost, but to a puny human on a scooter.) Watch out, humans, when we get our new 0.125″ aluminum shell.
We also met very very many cool people, far too many to list. Thanks to everyone who came out to help!
OK, so it’s not exactly our party, but as dedicated camp followers of the Flaming Lotus Girls we are going to crash theirs.
Details at the Squid List: Flaming Lotus Girls Mellow Toga Party.
Yes, it’s a Toga Party. Yes, you are expected to wear a toga. Come and mingle with the SWARMers and Loti. Wearing togas.
I have a reasonable suspicion that there may be alcohol involved.
Too many posts without a picture. Here’s our logo: share & enjoy!
So Mike spent the weekend upgrading the shell and last night we drove it around some more. It’s getting there! Much smoother rolling and more robust. It was good to see how well it would stop and start. The drivetrain is working really well, though the steering has some issues. We took the Orb to the parking lot: it has no problem rolling up minor hills, but steering is tricky, and we also took it to the park so it could play on grass for the first time in its young life.
Still some issues: we found that the steering motor gearhead was jumping teeth, so we’ll need one with metal gears instead of plastic. Once we get that going then we can start to tune the steering motor control. Lots more things to do: mount the prototype circuit boards, lots of software development. Anyone interested, please get in touch: info@orbswarm.com
We also hung a door on our little elevated space at the Box Shop. Now I’m afraid I can’t call it anything but the “SWARM Dorm.”
So we “open-dorked” [informally presented] the SWARM project at last night’s Dorkbot. Though we had some tough acts to follow, like author Rudy Rucker and Mark Powell’s ant-flavored gumdrops, a small cheer went up when we put up the first SWARM slide. (I suspect ringers in the audience.)
The presentation went over well, and I think we have some excellent new recruits. More pictures here.
Thanks Lisa for the video. Got it streaming raht cheer:
Good news everyone! We have a rolling orb as of last night. It doesn’t steer yet and the drivetrain needs some work, but she rolls under her own power. Videos up Real Soon Now.
This came together impressively quickly: I am consistently awed by this team. A big thanks to everyone — you know who you are.
