ROBOTMAK3RS Blog

First, I'm sad to say that the recently posted (& fantastic!) image of balloon shards falling to earth was not from my payload Gypsy, but from Eric Wang's SLR payload. It seems that for some reason (Gremlins? Bionicles? Jack Stone?), Gypsy's SD card is empty - the payload took an initial picture upon start-up (as it's supposed to, to show it was working), but for some reason it didn't work after that. I've no idea what went wrong, and it's very troubling (& you can BET I'm going to try to figure it out)... but that's some of the risks & mysteries of this sort of thing. To be honest, overall I'm still amazed at how well it went. The team took a big gamble on having Lil' Joe free-fall - it was risky (for their equipment), and required them to do three retrievals when usually they have to do just one. Yet Lil' Joe worked. Well, close anyway... I'll put up some data graphs soon, but Lil' Joe had a rough ride, slamming i...

8:16 AM EDT, 5:16 AM PDT: Today is the launch day, and it looks like the team has gotten things started (it's 8:07 AM here, but 5:07 AM at the launch site). Unfortunately it looks the public view page for the SPOT units isn't working at the moment, but I'll try to keep you in the loop via edits to this blog post, and the ham radio links at KD7UCE-11 and KE7BQV-11 should be up soon. The launch site sits at roughly 4,700', and the team camped at it last night - the first SPOT tracking data of the morning just came on-line about 5:07 local time at the launch site, so things are starting to happen. 9:52 EDT, 6:52 PDT: LAUNCH! Balloon #2, carrying an SLR camera payload, FLL Team 90's payload, the LEGO Mindstorms Team's payload, Gypsy, Lil' Joe, and the "NXT" communications payload just launched from the Nevada desert! Everything looks good at launch, although conditions have gotten slightly windier... but it's going up! Next launch in perhaps 30 ...

While Lil’ Joe sports a fairly simple program, Gypsy ended up as one of the more complex programs I’ve written in NXT-G. The program (still named “Nadar”) really needed to handle several different tasks at once. Primarily a photographic platform, it had to be able to operate the camera in both still & video modes, and take interesting pictures while controlling the platform. As a secondary goal, it needed to datalog the numerous environmental sensors hooked up, as well as “engineering data” (like battery voltage, platform angle, motor noise, etc.). On top of this, it needed to monitor and control the payload temperature, critical to keeping the payload alive. And to complicate all of this, the program needed to be as small as possible, leaving as much memory as possible for datalogging. In order to handle the photographic challenge, the program uses the same approach as the original Nadar: following a script . It reads a series of timed commands from a text file (think of it as a “...

There's been some new information posted at the HALE website that I thought might make for a fun heads-up on the mission. First, the payload allocations for the two balloons has been put up. Each balloon will be carrying a ham radio that will transmit GPS information down, as well as a SPOT transmitter that will be doing the same thing. The first balloon will carry: LUXPAK, Brix-Catcher, Peeps-in-Space, a separate student payload (no name), the "Energizer" communications payload Reel-E, & a video camera payload (a.k.a National Instruments) designed to "look up" through the mission to try to get video of the dynamics at cut down (OK... what it looks like to have your balloon pop 100,000' above the ground). The second balloon will lift several more payloads: a SLR camera payload that has flown before, FLL Team 90, the LEGO Mindstorms Teams submission, Gypsy, Lil' Joe, & a "Giant NXT" communications payload. The communication payloads are...

Gypsy is the second of my two payloads on the HALE mission , and while somewhat less risky, it’s far more complex. It’s based on an earlier prototype I built called “Nadar” , (named after the first person to do aerial photography). The idea was simple: I wanted to make a payload that would control an otherwise unmodified (no cutting & soldering) camera to take both pictures and video. That required not only a small camera, but one the NXT could be used to switch between modes on, from still to video & back again. I ended up with a Nikon COOLPIX L11, which uses a slider switch on the back to switch between modes. With some difficulty, I came up with a LEGO lead screw assembly that would reliably move the switch, and a second motor that could press both the power and the shutter button. That left the third motor to control where the camera was pointed. I played with the idea of a rotating mirror, but the mount for the mirror and the mirror itself represented a significant weight...

I recently returned from a wonderful week-long vacation in the Rocky Mountains here in the US, and of course took along the NXT. I mentioned before that I was trying to get the NXT to function as a pedometer to record footsteps for a project I was working on. Well, I didn't get the pedometer working, but I certainly had fun on the project... The HALE mission is rapidly approaching, and one of the things I wanted to do on my payload was fly a good pressure sensor. A really good one, with possible vertical resolution in the range of a meter or better. After some discussion with the folks over at Hitechnic, they were able to put together a prototype for me to fly with very high resolution. But how to test it? First, I made a small vacuum chamber from a Tupperware bowl, aquarium supplies, and a large-bore syringe, testing it out under hot sun & in my freezer (my wife did look at me a little funny...). It worked rather well, but I wanted more. Since ultimately the HALE pressure da...

Event will take place July 28-August 2 in Reno, Nevada.