highaltitude.log.20070409

[00:05] edwardmoore (n=edwardmo@88.212.167.121) left irc: "toodle-pip"
[00:40] flowolf (n=flowolf@host136-203.pool62211.interbusiness.it) left irc: "Leaving"
[00:54] Ebola (n=Ebola@host86-136-130-202.range86-136.btcentralplus.com) left irc: "gone"
[01:43] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[04:31] Professor (n=bobd@x-division.com) joined #highaltitude.
[04:31] <Professor> hello
[04:31] Professor (n=bobd@x-division.com) left irc: Client Quit
[07:14] jcoxon (n=jcoxon@81-178-247-220.dsl.pipex.com) joined #highaltitude.
[07:26] <icez> howdy jcoxon
[07:27] <jcoxon> hey icez
[07:46] <jcoxon> icez, http://wiki.ukhas.org.uk/projects:groundcontrol
[07:46] <jcoxon> :-D
[07:47] <icez> cool:)
[07:47] <icez> you know, you could create a special page using the Google Maps API to get rid of all the extras of the website too
[07:48] <icez> oops
[07:48] <icez> nevermind:)
[07:50] <jcoxon> hehe
[07:50] <jcoxon> didn't actually think that embedding that would work but somehow it did
[07:51] <icez> well, you could still remove the webpage and have only the map on a webpage:p
[07:52] <jcoxon> yeah
[07:52] <jcoxon> thats the plan
[07:52] <icez> oh, I have to build a rocket for my math class (weird, I know)
[07:52] <icez> :p
[07:53] <jcoxon> cool
[07:53] <icez> going to call it Calculus Express :/
[07:54] <jcoxon> hehe
[07:56] <icez> I don't know if we'll get permission from the college to launch it on the football field though :)
[08:06] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: Remote closed the connection
[09:42] flowolf (n=flowolf@62.211.203.136) joined #highaltitude.
[10:12] jcoxon (n=jcoxon@81-178-247-220.dsl.pipex.com) left irc: "Leaving"
[10:35] flowolf (n=flowolf@62.211.203.136) left irc: "Leaving"
[12:04] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[12:15] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[12:17] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[12:34] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[12:38] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[13:02] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[13:35] Ebola (n=Ebola@host86-136-130-202.range86-136.btcentralplus.com) joined #highaltitude.
[14:18] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[14:25] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) joined #highaltitude.
[14:37] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[15:03] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[15:31] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) joined #highaltitude.
[16:22] <edwardmoore> hi jcoxon
[16:53] <jcoxon> hey ed
[16:58] Action: jcoxon is back in cambridge
[17:07] <edwardmoore> sorry back
[17:07] <edwardmoore> nice weather there?
[17:12] <jcoxon> up
[17:12] <jcoxon> yup*
[17:12] <jcoxon> full of tourists
[17:13] <edwardmoore> aye
[17:14] <edwardmoore> it was on Flog It today
[17:14] <edwardmoore> the granny-friendly presenter was being given a punt
[17:17] <jcoxon> hehe
[17:17] <jcoxon> i love flog it
[17:17] <jcoxon> though i was terribly upset with the presenter change of cash in the attic
[17:17] <jcoxon> jennie bond shouldn't be allowed to present it
[17:18] <jcoxon> she is too mean to the poor people
[17:18] <jcoxon> "oh how gastly you house is - it'll never earn ANY money at auction..."
[17:29] <edwardmoore> i hate jennie bond
[17:30] <edwardmoore> she's on great british cook-a-thon or something
[17:30] <edwardmoore> and keeps commenting with really silly banter
[17:30] <edwardmoore> "you tell him, heston"
[17:30] <edwardmoore> "dig that knife in, charles"
[17:36] <jcoxon> haha
[17:37] <jcoxon> when are you planning to get back?
[17:47] flowolf (n=flowolf@62.211.203.136) joined #highaltitude.
[17:48] <edwardmoore> sorry i turned the sound off the irc client and now keep forgetting about it
[17:48] <edwardmoore> i'm not back will the 21st
[17:48] <edwardmoore> till*
[17:50] <jcoxon> its okay - i'm unpacking at the sametime as chatting
[17:50] <jcoxon> right okay cool
[18:13] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[18:28] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[19:03] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[19:25] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[19:34] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[19:39] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[19:45] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[20:23] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) joined #highaltitude.
[20:24] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) left irc: Client Quit
[20:33] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) joined #highaltitude.
[20:34] <mc-> http://www.aeroconsystems.com/electronics/nichrome.htm#hothead
[20:34] <mc-> I was thinking of buying some ematches
[20:36] <mc-> or is it easier to use a low value resistor?
[20:43] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) left irc:
[21:06] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[21:10] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) joined #highaltitude.
[21:11] <mc-> edwardmoore, was it your rocket you launched, or am I mixing you up?
[21:12] <edwardmoore> not I, sir
[21:12] <mc-> must have been henry then
[21:12] <edwardmoore> still building my L1 attempt
[21:12] <edwardmoore> rocket from a balloon?
[21:12] <mc-> yes
[21:12] <edwardmoore> oh yeah that was CUSF
[21:13] <edwardmoore> now found, which is good
[21:13] <mc-> do you need L1 to launch from a balloon?
[21:13] <edwardmoore> but the gps started sending 0.00000, 0.00000 after supposed rocket launch
[21:13] <edwardmoore> no, now amount of coverage will let you launch anything from a balloon ;)
[21:13] <edwardmoore> no amount*
[21:14] <edwardmoore> it's a entirely-at-your-own-risk thing
[21:14] <mc-> ok, that's what I thought, so I was thinking of launching after drifting out to sea
[21:14] <mc-> I've got some GPS modules, which are old, so I don't mind losing them.
[21:15] <edwardmoore> that's a brave man!
[21:15] <edwardmoore> what sort of thing were you considering launching?
[21:15] <edwardmoore> size-wise
[21:15] <mc-> start with an Estes
[21:15] <mc-> and work up from there
[21:16] <edwardmoore> sounds like an awesome project. kinda worth hiring a speed-boat though
[21:17] <mc-> well no, just let it fall in the sea, and lose it.
[21:17] <edwardmoore> you might be able to get it to land on you
[21:17] <mc-> yes, would be great to have a glider
[21:17] <edwardmoore> would this be with a view to a space shot?
[21:17] <mc-> one day
[21:18] <jcoxon> hey all
[21:18] <edwardmoore> hey jimbo
[21:18] <jcoxon> i was thinking today what would happen if we managed to organise say permission to launch a rockoon in say the sahara for next summer
[21:18] <mc-> btw what's SF in CUSF?
[21:18] <jcoxon> spaceflight
[21:19] <edwardmoore> space fugifilm
[21:19] <edwardmoore> i mean flight
[21:19] <mc-> a rockoon in sahara sounds great, but have to pay for flights to get there...
[21:19] <jcoxon> ?40 on easyjet
[21:19] <jcoxon> i did it in december
[21:19] <edwardmoore> quick as a flash
[21:20] <jcoxon> would it be possible
[21:20] <mc-> to morocco?
[21:20] <jcoxon> yup
[21:20] <jcoxon> do we have the expertise?
[21:20] <edwardmoore> we'd have our work cut out
[21:20] <edwardmoore> we'd need fully working active guidance
[21:20] <icez> why the sahara?
[21:21] <jcoxon> cause its easy to get to
[21:21] <jcoxon> and there aren't people - reduces risks
[21:21] <icez> and will they let you go with rocket stuff inside an airplane?:)
[21:21] <jcoxon> things i worry about
[21:21] <jcoxon> ship it out
[21:21] <mc-> you can take a hybrid on a plane
[21:21] <mc-> have to get nitrous out there
[21:22] <jcoxon> you can take weapons on a plane if they are declared
[21:22] <edwardmoore> hybrids on a plane
[21:22] <jcoxon> in the hold
[21:22] <edwardmoore> starring smuel L jackson
[21:22] <jcoxon> is it a mad idea?
[21:22] <jcoxon> perhaps 2 years time
[21:23] <jcoxon> or is that too much commitment
[21:23] <mc-> not sure what it saves on...I like the idea of landing in the sea for the moment, as avionics is cheap.
[21:23] <edwardmoore> it's not
[21:23] <mc-> it's cheap if you make it yourself
[21:23] <edwardmoore> not when you factor active guidance in
[21:24] <icez> make a balloon that launches a rocket which can also float back home?:)
[21:24] <mc-> I build a sun guidance system, the servos were the most expensive thing
[21:25] <edwardmoore> yeah- and they're not all that cheap
[21:25] <edwardmoore> for some really light but torquey digital ones, you have to shell out
[21:25] <edwardmoore> but james i agree it would be good to have something to work towards
[21:25] <mc-> true
[21:26] <jcoxon> but we do have things to work towards
[21:26] <jcoxon> i'd worry that this sort of idea would stagnate
[21:26] <edwardmoore> well, good to have some sort of compulsion
[21:26] <edwardmoore> if it all goes tits up, we could abandon it with 4 months to go i would have thought
[21:26] <jcoxon> it would take some serious organising
[21:27] <mc-> how about getting a guidance system going first, with some lowcost launches?
[21:27] <jcoxon> yeah mc- thats what i think we would do
[21:27] <mc-> then we're not taking huge leaps into the unknown
[21:27] <jcoxon> so do some ditching into the sea
[21:27] <jcoxon> as we wouldn't have long to do the real thing
[21:28] <jcoxon> basically we'd do gradual buildup working towards a final system
[21:28] <edwardmoore> i'm not so keen on ditching into the sea... would the plan be to get the guided return built into the rocket?
[21:28] <jcoxon> which would then be take out to africa and launched
[21:28] <jcoxon> i'm not sure
[21:28] <jcoxon> i don't think it would doable
[21:29] <jcoxon> considering hte path
[21:29] <jcoxon> perhaps for hte launch platform
[21:29] <icez> what kind of rockets are you guys thinking, to be afraid to hurt people?:P
[21:29] <edwardmoore> well i think we don't actually need a launch platform
[21:29] <edwardmoore> i think we should just take up the rocket
[21:29] <jcoxon> have the rocket correct itself?
[21:30] <edwardmoore> yeah- i was talking to steve and we both intuitivelly feel that active guidance will be necessary
[21:30] <edwardmoore> i'm still really not all that convinced by tube launching
[21:30] <jcoxon> hmmmm
[21:31] <jcoxon> the problem i see is the leap to a final model
[21:31] <jcoxon> without test launching in the UK
[21:31] <jcoxon> which i'm not the biggest fan of
[21:31] <edwardmoore> you're right i think
[21:31] <edwardmoore> it'd be a case of getting a working ground-launch rocket
[21:31] <edwardmoore> say a minimum diameter rocket on the biggest thing we can fit in it
[21:32] <edwardmoore> ground testing is advantageous in that it's a bit safer and easier
[21:32] <edwardmoore> then there would be a lead when we just have to take it up
[21:32] <jcoxon> okay
[21:32] <jcoxon> say we did that
[21:32] <edwardmoore> we could do launches from 1000ft from the ears site still
[21:32] <icez> do you guys know of any enormously small integrated GPS thingy (that saves some data on a memory chip, for example) that I could stick inside a small rocket?
[21:33] <edwardmoore> try sparkfun
[21:33] <jcoxon> say we did that
[21:33] <edwardmoore> uhuh
[21:33] <jcoxon> would it need to be done in africa
[21:33] <jcoxon> or would it be fine to do it here
[21:33] <jcoxon> basically is it necessary to go else where
[21:33] <edwardmoore> a launch from high altitude is dodgy in the uk i think
[21:33] <jcoxon> thats how i feel
[21:34] <mc-> unless, it's launched out at sea, then I don't see any risk
[21:34] <edwardmoore> but we can do everything up to that (say, launches from 1000ft) here
[21:34] <edwardmoore> we'd need some money from somewhere
[21:34] <edwardmoore> i reckon the rocket would be a happy £1000 in materials
[21:35] <jcoxon> mc-, yeah true
[21:35] <jcoxon> however we would keep losing hte damn thing
[21:35] <mc-> I don't think it's that much, a hybrid costs around £100
[21:35] <edwardmoore> peanuts in commercial terms, but i don't think with our present unding structure (i.e. us) we could sustain ditching £1000 rockets into the sea. at least, i couldn't
[21:36] <edwardmoore> we can't really use a hybrid
[21:36] <edwardmoore> but a motor casing is around £100, yeah
[21:36] <edwardmoore> carbon fibre rocket
[21:36] <edwardmoore> machining for the actuation bit
[21:37] <mc-> a solid motor is fairly cheap
[21:37] <mc-> I know someone with a design for guidance, it didn't need much machining,
[21:37] <mc-> I'll ask if he has any spare bits for it
[21:37] <edwardmoore> inertial measurement unit would be about £100, other avionics about the same. A gumstix costs that on its own
[21:37] <edwardmoore> that'd be good
[21:38] <edwardmoore> except that we're dealing with the most high tolerance and pushed design we can get away with
[21:38] <mc-> could get samples of everything to get the cost down.
[21:38] <edwardmoore> for pure weight reasons
[21:38] <edwardmoore> they don't sample you gyros and acceleremoters. tried many a time :(
[21:39] <mc-> I've got several accelerometer samples, and have a gyro sample.
[21:39] <edwardmoore> i have no luck getting yummy ones from analogue devices. maybe they don't like me
[21:39] <mc-> I got accelerometer from memsic, and a gyro from AD a long time ago
[21:40] <mc-> probably everyone is trying to get samples, so it's difficult now
[21:40] <jcoxon> bbiab
[21:40] <edwardmoore> well it'd obviously be worth shopping around. but i still think parts would cost a lot
[21:41] <edwardmoore> like a said, mechanically you'd want everything to be carbon fibre or high temp alloys, none of which are peanuts
[21:41] <mc-> I can fund the sensors for the first few flights, I agree the other materials aren't cheap.
[21:41] <edwardmoore> i don't object to dumping cheaper testing rockets into the sea tho
[21:42] <edwardmoore> i guess we have room to experiment
[21:42] <edwardmoore> once i get my L1 I want to build a hybrid for L2 and to test active guidance
[21:42] <icez> I object! but it's not like I can stop you:p
[21:42] flowolf (n=flowolf@62.211.203.136) left irc: "Leaving"
[21:42] <edwardmoore> lol
[21:42] <mc-> how about a hybrid for the test flights, and then switch to solids for sea flights
[21:43] <edwardmoore> launching hybrids at altitude is a no-no
[21:43] <edwardmoore> unless we do some really illegal stuff!
[21:43] <mc-> I meant at ground level for testing guidance
[21:43] <edwardmoore> oh yeah, totally, sorry
[21:43] <edwardmoore> that's my intention
[21:44] <edwardmoore> much cheaper for repeated tests than shelling out on solids
[21:44] <mc-> I've got a rattworks hybrid, gathering dust
[21:44] <edwardmoore> what size?
[21:44] <mc-> I90
[21:44] <mc-> plus some reloads
[21:44] <edwardmoore> cool
[21:45] <mc-> just been thinking, it would be good to get the avionics back from a sea launch.
[21:45] <mc-> maybe the avionics can glide back by itself
[21:46] <mc-> and split up from the motor
[21:46] <edwardmoore> if you can glide stuff back, why bother ditching the motor?
[21:46] <mc-> true, but the avionics is light, so it needs a small wing
[21:47] <edwardmoore> lol but it needs wings :)
[21:47] <edwardmoore> if we can get the parafoil stuff working, there might be potential for getting it into rockets
[21:47] <mc-> I guess a small wing wouldn't add much weight,
[21:48] <mc-> how do you deploy a parafoil from a rocket?
[21:48] <edwardmoore> will tell you when i work it out
[21:48] <edwardmoore> :)
[21:48] <mc-> that's why I thought a small wing is easier.
[21:49] <edwardmoore> would this be a deplotable wing?
[21:49] <edwardmoore> deployable*
[21:49] <mc-> no
[21:49] <mc-> more like a boosted glider
[21:49] <edwardmoore> ok
[21:49] <mc-> if the rocket was launched just over the sea, then the glider
[21:49] <mc-> doesn't have far to get back to land
[21:50] <edwardmoore> the only problem is the legality of gliders
[21:50] <edwardmoore> in that they're not legal.
[21:51] <mc-> didn't know that
[21:51] <edwardmoore> that's why we were looking at parafoils
[21:51] <edwardmoore> the CAA gets very upset
[21:54] <mc-> is a semi-gliding stage followed by a parachute legal?
[21:55] <edwardmoore> a what?
[21:56] <mc-> or a glider followed by a parachute legal?
[21:57] <mc-> it could be done with just a chute, if the sea launch is in a channel.
[21:57] <mc-> If the chute deploys the payloads drifts over to land.
[21:57] <mc-> e.g. bristol channel
[21:59] <mc-> or over the wash, provided the winds are in the right direction
[22:00] <edwardmoore> ok- so such that the winds push the thing back over land?
[22:00] <mc-> yep, btw, what's the problem with launching hybrids from a balloon?
[22:00] <edwardmoore> as it stands, you can't launch pressurised canisters
[22:00] <edwardmoore> so hybrids have needle-holes in them
[22:01] <edwardmoore> which is why they vent whilst waiting to launch
[22:01] <mc-> is it legal, if the vent can be opened/shut by radio control?
[22:01] <edwardmoore> and why at launches they do it all within about 4 seconds of the fill valve closing- to stop it all venting away
[22:01] <edwardmoore> no it's not legal
[22:01] <edwardmoore> however that's not the big problem
[22:02] <edwardmoore> the big promblem is that 900psi of nitrogen
[22:02] <edwardmoore> woops
[22:02] <edwardmoore> is that at -50 degrees celcius, it's go from like 900psi (required) to significantly less
[22:03] <mc-> yes, you'd need a way to heat the nitrous during the ballon flight
[22:03] <mc-> or even just at the end of the flight to raise the pressure
[22:03] <edwardmoore> you'd need a huge amount of heat
[22:04] <mc-> you're right, it probably easier to just use a solid motor.
[22:04] <edwardmoore> i haven't done the maths but i think it would be kilowatts over the few seconds of burn
[22:04] <edwardmoore> also hybrids don't have the power/weight of solids
[22:04] <edwardmoore> and they're harder to ignite
[22:05] <edwardmoore> yeah i think solids would be a bit more reliable for something of this size
[22:06] <mc-> I don't think a large solid is required to get to 100km.
[22:06] <mc-> there's not much drag at 30km.
[22:06] <edwardmoore> it's all about velocity
[22:06] <mc-> or acceleration..
[22:07] <mc-> with a small payload, can get large acceleration
[22:07] <edwardmoore> well, velocity determines your final height
[22:07] <mc-> true
[22:07] <edwardmoore> if you're ignoring drag which you can do
[22:07] <edwardmoore> so basically given the weight of the rocket, we need the motor that'll give us the velocity we need at the end of the burn
[22:08] <mc-> so the problems to be solved are: guidance, recovery, and a test program
[22:08] <edwardmoore> which is why i want to spend ££££ of CF and very accuratelly machined high temp alloy guidance hardware ;0
[22:08] <edwardmoore> yeah
[22:09] <edwardmoore> however, the sahara thing would make the recovery problem less of a problem
[22:09] <mc-> how about a low cost flight to get experience with CF etc, then start to add the bells&whistles
[22:09] <mc-> *without CF
[22:10] <edwardmoore> yeah i mentioned that a bit above
[22:10] <edwardmoore> then build the final thing and ground launch test it very thoroughly
[22:10] <edwardmoore> and maybe at reasonable altitudes
[22:11] <edwardmoore> and hopefully the cheaper high altitude tests should tell us what we need to know about how the elctronics and stuff hold up at 30g and many kilometers
[22:11] <mc-> I've got most of the bits to build avionics+low cost servos.
[22:12] <mc-> That should get us far way into a test program
[22:12] <mc-> *fair
[22:13] <edwardmoore> ok cool
[22:13] <edwardmoore> we need a dogsbody rocket to stick it all in
[22:13] <mc-> I've got GPS modules, + PCBs for PICs
[22:13] <mc-> rocketboy might have a dogsbody rocket to hand
[22:13] <edwardmoore> I've got some DSPics for the attitude measurement
[22:14] <edwardmoore> i was going to make a 4" rocket for my L2 and for active testing
[22:14] <mc-> which 4" rocket?
[22:15] <edwardmoore> a home-build
[22:15] <edwardmoore> gives a bit more room so we can do more prototyping and less space optimising
[22:15] <mc-> sounds good
[22:16] <mc-> I can't start on the guidance for a few weeks, too much work at the moment.
[22:16] <mc-> I'll dig out my sun guidance system though
[22:16] <edwardmoore> same. I kinda have to get exams out the way before i throw myself at this
[22:17] <mc-> sun guidance is good, because the sun isn't overhead
[22:17] <edwardmoore> how accurate to you reckon the sun guidance is? it's a new thing to me
[22:17] <edwardmoore> it probably would be in the sahara :p
[22:17] <mc-> it should be good enough to point roughly towards the sun.
[22:18] <mc-> it's just some LDRs+PIC+servos
[22:18] <edwardmoore> but if the sun isn't overhead, surely that's a bad thing?
[22:18] <mc-> you can see if the guidance is working, when the sun isn't overhead
[22:19] <mc-> must go to sleep, cya
[22:19] <edwardmoore> ok- but that limits you then to noon launches?
[22:19] <mc-> yes, noon for a proper flight
[22:19] <edwardmoore> ok
[22:20] <edwardmoore> well, sleep well
[22:20] mc- (n=mfcastle@cpc2-glfd1-0-0-cust995.glfd.cable.ntl.com) left irc:
[22:41] <jcoxon> long conversation
[22:43] <jcoxon> shall have a think
[22:43] <edwardmoore> whose?
[22:43] <jcoxon> you and mc- while i was away
[22:44] <edwardmoore> oh yeah
[22:44] <jcoxon> i shall have a think about this crazy idea
[22:44] <jcoxon> and also parafoil deployment
[22:45] <edwardmoore> it's a cool crazy idea
[22:45] <edwardmoore> yes it is
[22:48] Laurenceb (n=laurence@host86-136-160-36.range86-136.btcentralplus.com) joined #highaltitude.
[22:48] <Laurenceb> Hi all
[22:48] <jcoxon> hey Laurenceb
[22:48] <jcoxon> sorry to say i'm off to bed
[22:48] <Laurenceb> I've come up with
[22:48] <Laurenceb> a use for the new gumstix
[22:49] <edwardmoore> ?
[22:49] <Laurenceb> if you had a webcam
[22:49] <Laurenceb> and could capture images
[22:49] <Laurenceb> you could use image recognition to find the horizon
[22:49] <Laurenceb> and also turn rates
[22:50] <Laurenceb> should be able to get pitch and roll
[22:50] <Laurenceb> and also a 3 axis rate gyro
[22:51] <Laurenceb> there are loads of libraries around for doing that sort of thing
[22:52] <edwardmoore> uhuh
[22:53] <edwardmoore> that'd be cool, *but*
[22:53] <edwardmoore> surely there are much easier, more accurate and more reliable ways?
[22:53] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: "Leaving"
[22:53] <Laurenceb> yes but not as cool
[22:54] <Laurenceb> you would probably need a high res camera
[22:54] <edwardmoore> lol, i can't argue with you there
[23:01] defy (n=defy@60-234-174-220.bitstream.orcon.net.nz) joined #highaltitude.
[23:02] <Laurenceb> It'd be good on a uav helicopter
[23:02] <defy> hey guys
[23:02] <Laurenceb> hi there
[23:02] <Laurenceb> I was just thinking about the new gumstix
[23:02] <defy> theres a new one?
[23:03] <Laurenceb> you could use image recognition with a usb camera
[23:03] <defy> thats not good..that means ill have to buy it :(
[23:03] <Laurenceb> it has 600mhz and usb host
[23:03] <defy> ...dont tell me they released one with a usb host?
[23:03] <defy> ah! awesome
[23:03] <Laurenceb> yes
[23:03] <defy> *orders*
[23:03] rocketboy (n=steve@host86-140-238-223.range86-140.btcentralplus.com) joined #highaltitude.
[23:03] <Laurenceb> so you can have a usb camera
[23:04] <Laurenceb> and then have some horizon finding code
[23:04] <Laurenceb> and something similar to the technique optical mice use, to get rate gyro data
[23:04] <Laurenceb> -rate gyro type data
[23:05] <defy> I've been waiting a pretty long time for a usb host, but i honestly didnt think they would release it this year
[23:05] <edwardmoore> or..... use a rate gyro
[23:05] <edwardmoore> *ducks*
[23:05] <Laurenceb> problem is getting pitch and roll ect
[23:05] <edwardmoore> hi steve
[23:05] <defy> yea i dunno if i'd trust a webcam to keep something level, thermo's and gyro's do a nice job
[23:06] <defy> but a usb host is definately a good thing
[23:06] <Laurenceb> thermos arnt foolproof though, if the code was good, I'd trust a camera more
[23:07] <defy> whats wrong with thermos exactly? they've worked perfectly for me
[23:07] <defy> in all types of weather etc..
[23:07] <Laurenceb> you can use accelerometer, magnetometer, rate gyro and a kalman filter
[23:07] <Laurenceb> hmm interesting, I havent tried it
[23:07] <defy> a webcam would rely too heavily on your pitch being correct
[23:07] <defy> and a clear day etc etc
[23:08] <Laurenceb> yes... I was just going off some papers on thermo performance I had read, never tried it
[23:08] <defy> i had my plane flying out in the fod with the thermos and they still kept it level...they were a LOT less sensitive but they still worked
[23:08] <defy> err, fod=fog
[23:08] <Laurenceb> cool
[23:08] <defy> yea i'm pretty gutted that the place i got them from doesn't sell them any more
[23:09] <defy> ill have to make my own if i want more :(
[23:09] <Laurenceb> thermos that is?
[23:09] <defy> yeah
[23:09] <defy> well, not the thermopiles themselves
[23:09] <Laurenceb> you could gut an ear thermometer
[23:10] <defy> the sensors themselves are dirt cheap
[23:10] <Laurenceb> well, if you can find the right supplier
[23:10] <defy> for just the stand alone sensors? they're all over the place
[23:10] <defy> its the complete boards i'm not having issues finding
[23:10] <Laurenceb> like??
[23:11] <Laurenceb> I've been looking for ages for a supplier
[23:11] <defy> google thermopile sensors
[23:11] <Laurenceb> we needed some for an experiment at uni, and had to ship them in from a uni in germany
[23:11] <Laurenceb> couldnt get any from anywhere
[23:12] <defy> i found some a few weeks ago
[23:12] <defy> ill try to find the site
[23:13] <defy> http://www.melexis.com/ProdMain.aspx?nID=19
[23:13] <defy> straight from the people who make them :P
[23:13] <Laurenceb> we cooled them down with LN2 and picked up submillimeter radiation
[23:13] <Laurenceb> it was for a millimeter wave fourier spectrometer
[23:15] <Laurenceb> oh cool thanx for the link
[23:15] <defy> np
[23:16] <defy> wow that site is actually quite expensive though
[23:16] <Laurenceb> but.. its cheaper to buy the fma units than those
[23:17] <defy> both of my thermopile boards, which have 4 sensors each on them, were under $50 usd
[23:17] <Laurenceb> yes, fma sell them for$40
[23:17] <defy> I'm sure i've seen them cheaper though
[23:17] <Laurenceb> google fma direct
[23:18] <defy> ahh, those look like the ones that the paparazzi project uses
[23:18] <Laurenceb> yep
[23:19] <defy> looks like its pwm output though
[23:20] <defy> http://www.uavs.net/ has the schematic for the ones i have if you're interested
[23:20] <Laurenceb> really?
[23:20] <Laurenceb> I got the impression it was analogue
[23:20] <defy> ah, maybe it is
[23:20] <Laurenceb> from paparazzi
[23:20] <defy> I'm not sure...I'd prefer analog though
[23:21] <Laurenceb> paparazzi have a pinout, sure its analogue
[23:28] <defy> i think i might actually wait a while to get the new gumstix...the last time i bought one of their newly released boards it had a lot of surprises we had to overcome
[23:33] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: "Leaving"
[23:39] <Laurenceb> cya all
[23:42] rocketboy (n=steve@host86-140-238-223.range86-140.btcentralplus.com) left irc: "Leaving"
[23:42] Laurenceb (n=laurence@host86-136-160-36.range86-136.btcentralplus.com) left irc:
[23:47] Ebola (n=Ebola@host86-136-130-202.range86-136.btcentralplus.com) left irc: "Goned"
[23:50] edwardmoore (n=edwardmo@88.212.167.121) left irc: "toodle-pip"
[00:00] --- Tue Apr 10 2007