Tag : spacebridge-beta

Time flies like an arrow; fruit flies like a banana. 2010-03-27 10:48:00

10am: the designated meeting time. Noisebridge is empty. Camera battery on table with a plaintive note requesting someone to find a charger. I find the charger in the adjacent box.

10.27am: Chris arrives with a tiny video camera that arrived overnight for the launch. Nils and Ariel have also showed up in the meantime.

10.47am: donut run. Everybody is here. Assembly and final checks begin. Progress hampered by Saturday morning cartoons playing on the projector and PyCon preparations going on around.

11.27am: vox mode on ham radio working; we think both beacons should be visible. Setting up radio end-to-end test. In parallel, payload has been stencilled, trial assembly under way for final weighing. Cast up to 9 people, with at least three more to join on location.

11.47am: my updates are coming with creepy regularity. Still at Noisebridge; assembly of the multipart, multiplane payload is proving more challenging than expected. No APRS beacons have made it out yet, though this may be due to the poor radio permeability of the building.

12.00pm: the PyCon attendees are being very tolerant of our bellowing back and forth across the room while they’re trying to run talks. I’m alternating between shushing people and hiding behind the nearest pillar. Final weight comes in at 4 lbs 5 oz; sadly the stabilizing arms can’t take the weight without bowing alarmingly. Rapid replanning of support structure ensues. Still haven’t tested the radio gear.

12.21pm: packing up for departure. Drift trajectory estimate looks reasonable for our Alpha launch site.

12.56pm: all three cars on the road, connecting inverters and chargers in the car to top up batteries en route.

1.26pm: stuck in traffic near Livermore. So glamorous.

2pm: arrived at the California Qanat Aqueduct site, waiting for traffic-scattered posse. Made a foursquare location.

2.29pm: wind is blowing in an unfortunate direction. Condoms Meteorological

2.45pm: checking skyvector.com confirms that all the local airfields are reporting winds blowing north or north-east. Ozzy uses his pilot contacts to confirm that high-level winds are still blowing towards the east, so we only need to worry about the lowest 15,000 feet of ascent and descent. We decide to get another 10-15 miles east/south-east before launching.

2.59pm: confusion ensues due to phones redirecting to voicemail and partially meshed radio contact between vehicles – cavalcade count now up to 5, and uncertainty if all heads found seats.

3.02pm – interlude: we’re running very late, once again, and although none of the reasons are exactly the same as they were last time, the general problem is that too many individual tasks are still being tweaked, refined (or in some cases started) in the few days before launch. We’re deadline driven, but not very good at planning back from the deadline.

4pm: we spot an airstrip on our way south, and decide to try our luck. After a long and frustrating wait while attempts to contact the airstrip owner via friends of friends are made, the BATF (Bar of Alcohol, Tobacco and Firearms) point out that since they have permission to shoot automatic weapons at the airstrip, they feel entitled to grant us permission to launch a balloon. It’s on.

4.20pm: …or is it? The helium cylinder turns out to have been less than half-full. Perhaps a leaky valve that vented gas over the past month? We have the balloon at approximately neutral buoyancy. So… if we remove the skirt from the balloon, we might be able to cobble together a light enough payload to lift, by duct-taping together a G1, radio and camera. Drama!

4.48pm: Snatching victory from the jaws of defeat, Blake returns from a foraging expedition with a 73 cu ft cylinder of helium, acquired from a local party balloon filling place. The balloon has lift – next we assemble the entire payload string and see how much excess lift we have. If not enough, we’ll have to shave the payload down.

5.09pm: And I thought we launched late last time :P Balloon is filled with all the helium we can get. Electronics are all on, text messages with GPS co-ordinates are coming in; both APRS beacons are being received. Last zip-ties being attached now.

5.24pm: Not enough lift. Luckily, the heaviest camera doesn’t work with the lithium batteries that we bought anyway, so we can remove that. The balloon skirt is also being removed. In worse news, after the first few SMSes, the Android fell silent.

5.57pm: Heartache and angst as people’s favourite projects are ruthlessly culled to reduce weight. Stand-by Android with old SMS code resurrected in the hope that it will send reliably.

6.53pm: not enough lift to clear the trees with even the most minimal payload. We scrub, clean up, and retire to the nearest hotel for food and consolatory champagne.

Categories: Spacebridge, Syndicated

Time flies like an arrow; fruit flies like a banana. 2010-03-26 22:32:00

Friday night before launch, and once again we start from having no working radio beacons. But unlike last time, we have some seriously impressive looking Sputnik-like payload. One of the major worries from the previous launch was the internal temperature, reported at -21C at one point.

This time, we have a solid block of styrofoam with voids carved into it for individual pieces of equipment, some of which are further wrapped in aluminized mylar for additional insulation; some of which have active heating internally in the form of a power resistor across a 9V battery.

We’re optimistic.

Similarly exciting, although we’re flying the same APRS tracker as last time, we also have new APRS softmodem code for the Android, meaning that it will alternate transmitting position updates from its internal GPS with the known-working tracker.

That’s assuming that we can make it work together sensibly by 10am tomorrow, of course.

Other than that, we have extra cameras, including an IR experiment, and random updated bits and pieces. We may even manage to charge the batteries this time.

Categories: Spacebridge, Syndicated