Search found 66 matches

by Rris
Fri 17 Dec 17 2010 8:10 am
Forum: Space Balloon Project
Topic: Barometric altitude computation
Replies: 3
Views: 3877

Re: Barometric altitude computation

I asked Jonathan Fulford who was recently featured on the SFE news page about what pressure sensor he used. Sure. I used the Intersema MS5534C. I bought it from the DigiKey web site. It's the only sensor that I could find that would provide pressure data all the way from ground level to 100K feet. I...
by Rris
Thu 16 Dec 16 2010 4:54 pm
Forum: Space Balloon Project
Topic: Cygnus Module development
Replies: 20
Views: 10669

Re: Cygnus Module development

I dont think we need a balloon release mechanism. It will just pop when it gets high enough. Personally, i don't believe we need pan on the camera, tilt could be interesting though so you can get a down facing shot of the ground and a shot of the horizon. The only question is, how will servos (speci...
by Rris
Mon 13 Dec 13 2010 10:56 am
Forum: Space Balloon Project
Topic: Scorpion Controller Board
Replies: 19
Views: 11985

Re: Scorpion Controller Board

As a reminder, i need to change the USB host to a vertical port rather than horizontal, this will save some space.
by Rris
Fri 10 Dec 10 2010 8:11 pm
Forum: Space Balloon Project
Topic: Cygnus Module development
Replies: 20
Views: 10669

Re: Cygnus Module development

I think 3hrs would be the max flight time. Balloon calcs reckon 2:45 or so. I'm working on a 3.5hr budget.
by Rris
Thu 09 Dec 09 2010 8:59 pm
Forum: Space Balloon Project
Topic: Scorpion Controller Board
Replies: 19
Views: 11985

Re: Scorpion Controller Board

Made footprints for the 4020 Inductor footprint, and LM60 temp sensor. So the GPS and MCU now have isolated supplies with an inductor and large capacitance. The MCU gets C11 which was before an extra cap for the right hand side of the board (since 3.3v was on the left before). The GPS gets an extra ...
by Rris
Thu 09 Dec 09 2010 6:15 pm
Forum: Space Balloon Project
Topic: Scorpion Controller Board
Replies: 19
Views: 11985

Re: Scorpion Controller Board

The only RF shield high enough to take an inductor is BMI-S-207-F. This is 1.747" (44.37mm) x 1.747" (44.37mm) x 0.384" (9.75mm) which is pretty big. Fotofab also make some, but you need to bend them yourself it appears - they look like just flat stamped out or laser cut then embossed tin. Very expe...
by Rris
Thu 09 Dec 09 2010 1:20 pm
Forum: Space Balloon Project
Topic: Scorpion Software
Replies: 3
Views: 3836

Scorpion Software

Thesea re my initial thoughts on a protocol for sending data down. It runs at 432bps at 1hz. At 2400bps comms rate, i'm using just 18% of it's capacity. General Packet Structure (12 bytes/96 bits) 16 0x23,0x23 Sync 8 [byte] Packet type (sequential enum value) 8 [byte] Packet ID (sequentially numbere...
by Rris
Thu 09 Dec 09 2010 11:48 am
Forum: Space Balloon Project
Topic: Batteries
Replies: 2
Views: 2930

Batteries

We need to test batteries which we might want to use onboard. I think at this point the options we have for batteries are: A123 cells Standard LiPo cells (Flightmax for eg) Newer LiPo cells (Turnigy Nanotech) NiMH cells Li-ion cells (like phone batteries) I require 13013mW of power including the reg...
by Rris
Thu 09 Dec 09 2010 12:11 am
Forum: Space Balloon Project
Topic: Scorpion Controller Board
Replies: 19
Views: 11985

Re: Scorpion Controller Board

Still need to add: * inductor from the micropsu to the GPS input supply. Perhaps a couple of the bigger MLCC caps i have reels of as well. * Inductor for the aerocomm (ultra low resistance) and another bigass cap (another 470uf/6.3v tantal?) * Aerocomm connector on bottom * Aerocomm txd/rxd leds * i...
by Rris
Wed 08 Dec 08 2010 11:43 pm
Forum: Space Balloon Project
Topic: Scorpion Controller Board
Replies: 19
Views: 11985

Re: Scorpion Controller Board

It all squishes down to a 86x68mm PCB. If i didnt have 3A power supplies on board, it could be smaller (81x43mm). Size doesnt really matter at this point - a 2.4ghz panel antenna we want to have as the base of the enclosure is fairly large! ScorpionPCBDay3.1.jpg I still need another voltage divider ...