highaltitude.log.20090204

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[00:00] <Laurenceb> hello
[00:01] <Laurenceb> jcoxon: what happened to the topic?
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[03:48] <natrium42> lol, the wtf-ness continues
[03:48] <natrium42> http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20090203/students_space_AM_090203/20090203?hub=TopStories
[03:55] <natrium42> :D
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[04:08] <josepharmbruster> natrium42: why do they make this out to be "big news" ?
[04:08] <josepharmbruster> natrium42: FYI: i'm taking my technicians exam tomorrow :-)
[04:14] <natrium42> josepharmbruster: reporters...
[04:14] <natrium42> josepharmbruster: cool, good luck
[04:18] <josepharmbruster> natrium42: ah... man, i'm excited
[04:18] <josepharmbruster> natrium42: in other news, I got my xtend-pkg modules in from digi
[04:20] <natrium42> nice
[04:20] <natrium42> did you play with them yet?
[04:21] <josepharmbruster> just a bit. left the base station at my window an drove down the street to see what type of range I could get
[04:21] <josepharmbruster> running 1W in an urban environment, i pulled about a half mile
[04:22] <natrium42> sounds about what i got too
[04:22] <josepharmbruster> XTend-PKG 900Mhz...
[04:22] <josepharmbruster> did you ever use em in the air?
[04:22] <natrium42> yes
[04:22] <josepharmbruster> tell me your experience with it
[04:22] <josepharmbruster> if you have a moment :-)
[04:24] <natrium42> sure
[04:24] <natrium42> i used a high gain omni antenna on the ground http://natrium42.com/gallery2/v/balloon/setup/main-chase-car.jpg.html?g2_imageViewsIndex=1
[04:24] <natrium42> and a 1/2 wave whip in the air
[04:24] <natrium42> that gave a range of about 6km altitude, 12km downrange
[04:25] <natrium42> after that contact was lost
[04:25] <josepharmbruster> ouch. how high did your balloon go?
[04:25] <josepharmbruster> did you use energizer lithiums?
[04:26] <natrium42> 30 km up
[04:26] <josepharmbruster> nice
[04:27] <josepharmbruster> how did the camera perform for you?
[04:27] <josepharmbruster> http://libjoe.blogspot.com/2009/01/weather-balloon-beginning.html
[04:27] <josepharmbruster> i have balloons :-)
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[04:28] <josepharmbruster> aw crap
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[04:28] <natrium42> wifi dropped
[04:28] <josepharmbruster> ooops
[04:29] <josepharmbruster> http://libjoe.blogspot.com/2009/01/weather-balloon-beginning.html
[04:29] <josepharmbruster> those are my balloons
[04:29] <josepharmbruster> man, so you packed all that hardware into the payload ?!?
[04:29] <josepharmbruster> seems like quite a bit of stuffs
[04:29] <josepharmbruster> let me keep clicking through the images
[04:30] <natrium42> my site is this, btw --> natrium42.com/halo/flight2
[04:30] <natrium42> i think if you use yagi antenna on the ground you will get enough range
[04:30] <natrium42> using omni antenna was stupid on my part
[04:31] <josepharmbruster> see, my situation is tricky
[04:31] <josepharmbruster> where i live, there's tons of water
[04:31] <josepharmbruster> so i have to make a floating payload
[04:32] <josepharmbruster> i still haven't designed it... i figure baby steps... get my radio license, so i can make a nicer aprs or such
[04:32] <natrium42> sure, then you don't need the xtend modules :)
[04:32] <josepharmbruster> man, i have that exact soldering unit
[04:32] <josepharmbruster> well, just one sec :-) hehehe.. i DO need the XTend modules
[04:32] <josepharmbruster> haha
[04:32] <natrium42> which one?
[04:32] <josepharmbruster> just don't have faith in them just yet
[04:32] <josepharmbruster> http://natrium42.com/gallery2/v/balloon/setup/IMG_3225.JPG.html
[04:33] <natrium42> aah, it's nice & cheap
[04:33] <josepharmbruster> so, are there any "recommended" gps modules for high-alt endeavors?
[04:35] <josepharmbruster> from what i've been reading, people seem to have all sorts of issues with them not functioning correctly at (or above) specific altitudes
[04:35] <natrium42> lassen iq is popular
[04:35] <natrium42> or the ublox modules
[04:37] <josepharmbruster> interesting, i'll have to check those out. im watching your video :-)
[04:37] <natrium42> hehe
[04:38] <josepharmbruster> so hey
[04:38] <josepharmbruster> when you lost communications above the 6k
[04:38] <josepharmbruster> how did you know where to drive / etc... ?
[04:41] <natrium42> i didn't have communications for that part of the flight because xtend went out of range :S
[04:41] <natrium42> but once it landed the cellular module sent the position
[04:42] <josepharmbruster> ah, just read that
[04:42] <josepharmbruster> oh man...
[04:42] <josepharmbruster> i can't let that happen :-)
[04:43] <natrium42> yeah, if you expect it to float, HF radio is a good idea
[04:44] <natrium42> or you could go with those globalstar satellite modules that send short messages
[04:44] <josepharmbruster> link?
[04:44] <natrium42> hrm
[04:44] <josepharmbruster> [ googling ]
[04:45] <natrium42> you could also use this http://en.wikipedia.org/wiki/SPOT_Satellite_Messenger
[04:46] <natrium42> they use this same globalstar satellite service afaik
[04:46] <josepharmbruster> man, those videos are great
[04:47] <natrium42> ty :)
[04:49] <josepharmbruster> findmespot.com
[04:51] <josepharmbruster> man, that's not a bad unit
[04:53] <natrium42> yeah, seems to be suited for your purpose
[04:57] <josepharmbruster> well thanks for the chat.. have to hit bed now.
[04:57] <josepharmbruster> work all day, then exam tomorrow 5:30
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[04:58] <natrium42> sure thing
[04:58] <natrium42> good luck on the exam!
[05:21] <natrium42> hmm, i decided to order that SPOT thingy too
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[12:14] <hallam> hello
[12:14] <hallam> fergusnoble: how high does the Yaesu go?
[12:15] <fergusnoble> in frequency?
[12:15] <fergusnoble> at least 438 i think
[12:15] <fergusnoble> its 439.99999
[12:15] <fergusnoble> acording to the manual
[12:16] <fergusnoble> for why?
[12:18] <hallam> listening to the Iranian satellite, I've got freqs
[12:18] <hallam> but it's 465MHz
[12:18] <fergusnoble> oh sucks
[12:18] <fergusnoble> ed's radio will probably do it
[12:18] <hallam> passes directly overhead at 1545h
[12:19] <fergusnoble> guess you cant see it in the day?
[12:19] <hallam> no but you might hear it
[12:20] <fergusnoble> yeah, cool
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[12:21] <fergusnoble> yup, ed's icom can do it
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[12:22] <hallam_> cool, might be interesting
[12:22] <hallam_> but I have lecture then
[12:22] <hallam_> would you like some chicken for lunch?
[12:29] <hallam_> fergusnoble: delicious chicken
[12:29] <fergusnoble> hmm... just had breakfast
[12:30] <fergusnoble> but its tempting
[12:31] <hallam_> I'm going to go try and find some bread
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[12:56] <SpeedEvil> np: Hallam - It's been 3 hours and 15 minutes. (And I still haven't found my bun)
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[13:02] <rjharrison> hi jiffe88
[13:02] <rjharrison> hi josepharmbruster
[13:04] <rjharrison> josepharmbruster: had a look at your wiki. I like the idea of sending up a cell phone
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[15:47] <Laurenceb> hi
[15:50] <SpeedEvil> Hi.
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[16:46] <jcoxon> afternoon all
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[17:35] <natrium42> hi jcoxon
[17:38] <jcoxon> hey natrium42
[17:38] <jcoxon> did you manage to receive any of Bill Brown's flight last weekend?
[17:38] <natrium42> was there another one with HF?
[17:39] <jcoxon> yeah
[17:39] <natrium42> d'oh
[17:39] <jcoxon> it was a sucess so he might now attempt a trans
[17:39] <natrium42> cool
[17:40] <Laurenceb> nice
[17:40] <Laurenceb> what frequency?
[17:41] <jcoxon> 14 something
[17:41] <natrium42> jcoxon: please let me know of a pending launch in case i do not keep track :)
[17:41] <jcoxon> i will
[17:41] <Laurenceb> 14MHz?
[17:42] <jcoxon> you should sign up to the ballooning yahoo group
[17:42] <jcoxon> Laurenceb, 14.077MHz
[17:42] <jcoxon> the something was the stuff after the decimal rather than the magnitude of Hz
[17:43] <Laurenceb> ok
[17:43] <Laurenceb> a bit low for me to receive
[17:45] <natrium42> jcoxon: i ordered the SPOT thingy btw
[17:45] <natrium42> have been thinking about hacking it to add sensor data
[17:45] <natrium42> the idea is to intercept the GPS lines with a microcontroller
[17:46] <natrium42> and send GPS locations which actually represent sensor data
[17:46] <jcoxon> SPOT thingy?
[17:46] <natrium42> findmespot.com
[17:46] <natrium42> it uses globalstar satellites
[17:47] <jcoxon> wow
[17:47] <natrium42> and the service is cheaper (and unlimited) compared to the globalstar short message module we talked about some time ago
[17:47] <natrium42> bbl food
[17:48] <shellevil> well - bandwidth limited surely
[17:50] <jcoxon> i'm intreged to know how they've got it so cheap
[17:51] <shellevil> tx only
[17:52] <jcoxon> i want a tx only sat module :-p
[17:53] <shellevil> I wonder if it's really tx only
[17:54] <shellevil> Or it just doesn't admit to rx too.
[17:55] <Laurenceb> http://www.bluetechnix.com/rainbow2006/site/hardware/core_modules/__tcm-bf537/315/tcm-bf537.aspx
[17:55] <Laurenceb> ~£150
[17:57] <Laurenceb> looks perfect for the CUSF rocket
[18:09] <natrium42> back
[18:10] <natrium42> jcoxon: i think it doesn't show altitude, but i will try to hack it in
[18:12] <shellevil> does it say update freq?
[18:12] <natrium42> 10 mins for the continuous tracking mode
[18:12] <Laurenceb> does it use gps?
[18:13] <natrium42> but you can also send location by pressing a button, so maybe you can do it more frequently
[18:13] <natrium42> Laurenceb: yes
[18:13] <Laurenceb> I see
[18:14] <jcoxon> cool cool
[18:14] <jcoxon> look forward to hearing your hacking successes!
[18:14] <jcoxon> right i'll bbl
[18:14] <natrium42> latr
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[18:18] <natrium42> lol, could even send very low res thumbnails
[18:18] <natrium42> 32x32, 2 bit
[18:18] <natrium42> that's about 32 messages to send
[18:19] <Laurenceb> how much per message?
[18:19] <natrium42> i took 8 bytes out of thin air
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[18:19] <Laurenceb> I mean cost
[18:20] <natrium42> it's unlimited
[18:20] <natrium42> $100 per year
[18:20] <Laurenceb> crazy
[18:20] <Laurenceb> so it just sends position?
[18:20] <natrium42> yes
[18:20] <Laurenceb> nice
[18:20] <Laurenceb> its got to be quite slow
[18:21] <natrium42> so all i need to do is splice in a microcontroller
[18:21] <Laurenceb> yeah
[18:21] <natrium42> and send positions from polar circle or something
[18:21] <natrium42> to represent altitude and sensor data
[18:24] <natrium42> i wonder how many significant figures it has for lat/lon
[18:24] <Laurenceb> must be quite accurate
[18:25] <Laurenceb> but it will send 32 bit floats if tis sensible
[18:25] <Laurenceb> so 8 bytes
[18:25] <Laurenceb> a float32 is a few meters on the surface
[18:26] <shellevil> If it doesn't filter of course
[18:27] <shellevil> Like it won't report locations if successive positions aren't within mach1
[18:27] <Laurenceb> yeah it could use integers relative to the last position
[18:27] <Laurenceb> like 4 bytes total
[18:32] <natrium42> i doubt it
[18:32] <natrium42> there is no guaranteed delivery
[18:32] <natrium42> so it has to send complete position each time
[18:46] <Laurenceb> cya
[18:48] <Laurenceb> http://www.chronos.co.uk/pages/comp/rubidium.php
[18:48] <natrium42> very nice, how much?
[18:48] <Laurenceb> dunno
[18:49] <Laurenceb> have to request a quiote
[18:49] <Laurenceb> better than one part inn 10^-11
[18:49] <Laurenceb> !
[18:50] <Laurenceb> anyway I'm off, cya
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[18:50] <natrium42> kk, later
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[19:23] <Laurenceb> hello again
[19:24] <Laurenceb> fergusnoble: ping
[19:24] <fergusnoble> Laurenceb: hello
[19:25] <Laurenceb> hey, I was wondering if you're using the surveyor board in the rocket
[19:26] <fergusnoble> yeah we probably are
[19:26] <Laurenceb> cool, sounds like a plan
[19:26] <Laurenceb> guess it just fits :P
[19:27] <fergusnoble> yup
[19:27] <Laurenceb> but it'll have to be vertically mounted
[19:27] <Laurenceb> have you made the nose yet?
[19:27] <fergusnoble> i guess it could be made smaller with one of those modules, but it works
[19:27] <fergusnoble> Laurenceb: yeah, we've made a nose
[19:27] <Laurenceb> fibreglass or CF?
[19:27] <fergusnoble> i think we want to mount it vertically anyway for the camera
[19:27] <fergusnoble> CF
[19:28] <Laurenceb> neat
[19:28] <Laurenceb> camera out of the front?
[19:28] <Laurenceb> wont the lens crack with the neat?
[19:29] <Laurenceb> or is there some perspex window or something?
[19:32] <Laurenceb> it makes parachutes a bit tricky
[19:33] <Laurenceb> guess you could have the blackfin and badger board either side of a lipo cell up the middle of the nosecone
[19:33] <Laurenceb> then a chute either side
[19:34] <Laurenceb> but it would require large cutouts for the chutes to deploy through in either side
[19:37] <Laurenceb> fergusnoble: I'd look at polyisocyanurate foam for filling the nose with
[19:37] <fergusnoble> we are having the tube split below the flight computer i think
[19:38] <fergusnoble> so it wont get in the way of the chute
[19:38] <fergusnoble> that foam looks cool
[19:39] <fergusnoble> it shouldnt get too hot hopefully
[19:39] <fergusnoble> the carbon can only do like 200C
[19:39] <fergusnoble> well, its the resin that goes, but yes
[19:39] <Laurenceb> you could get a bit more strengh from it
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[19:40] <Laurenceb> at the expense of having to chisle the tronics out
[19:40] <Laurenceb> so the nose is quite long?
[19:41] <Laurenceb> I have some cylinders of the stuff for making firebreaks in drywalls
[19:41] <Laurenceb> its required by building regs
[19:43] <Laurenceb> - I was just thinking of how to get the mass down as much as possible - also you really want two chutes, a small nylon one first, then a larger polythene one would be really light
[19:47] <Laurenceb> nylon say 15cm slows you to 50mph or something, then a 70cm or something polythene one for landing. Hopefully total mass could be as low as 50grams total for the two chutes
[19:51] <Laurenceb> polyisocyanurate starts to degrade above 177C
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[20:55] <natrium42> hi G8KHW
[20:59] <G8KHW> hiya - looks like I might have a FT817ND on the way to me (I hope)
[20:59] <natrium42> cool
[21:01] <G8KHW> I just ordered one up at the old price (before the £ droped like a stone) - and I got an email confirmation - but you never know until you get it
[21:10] <fergusnoble> Laurenceb: unfortunately the recovery is going to have to be a bit more substantial than that, its quite a worry
[21:11] <Laurenceb> http://www.b3tards.com/u/899d78c16b9bb1676226/iran_first_satellite_sml.jpg
[21:11] <Laurenceb> fergusnoble: yeah
[21:11] <fergusnoble> will be going serious mach when it starts to reenter
[21:11] <Laurenceb> why not wait till you are very low
[21:11] <Laurenceb> that was what I was thinking with that plan
[21:11] <fergusnoble> quick calcs show kN opening forces on any chute
[21:11] <Laurenceb> ~5Km
[21:12] <Laurenceb> 240mph
[21:12] <Laurenceb> if its a small 6 inch job its not a bad
[21:12] <fergusnoble> trouble is, its so pointy that if you dont start doing something quite high you dont really slow down enough
[21:12] <Laurenceb> just to get the speed down to 45mph or something where you can open a nice big flimsy 20um polythene job
[21:13] <Laurenceb> hallam said terminal velocity was 240mph near the ground
[21:14] <fergusnoble> could be, that may be based on his model, iain has the full model of the drag etc
[21:14] <fergusnoble> but sounds reasonable
[21:14] <Laurenceb> yeah he was looking at the model results
[21:14] <Laurenceb> I think its the best plan
[21:14] <fergusnoble> but still, opening any chute is going to be nasty at 240mph
[21:14] <Laurenceb> yeah
[21:15] <fergusnoble> will have to be kevlar or something
[21:15] <Laurenceb> so it wants to be as small as poss
[21:15] <Laurenceb> hopefully nylon would be fine
[21:15] <Laurenceb> but its the mounting thats the issue
[21:15] <Laurenceb> or it will rip off the CF body
[21:16] <Laurenceb> ballute?
[21:17] <fergusnoble> ballute is complex, would be good to avoid it
[21:17] <Laurenceb> yeah
[21:17] <Laurenceb> I thought of a nylong line with lots on mini chutes on
[21:17] <fergusnoble> at 5km you are only 40 seconds away from the ground
[21:17] <Laurenceb> but deploying it is hard
[21:18] <Laurenceb> plenty of time :P
[21:18] <Laurenceb> you'd probably be able to deploy the poythene chute in <10seconds
[21:18] <Laurenceb> from the nyplon one firing
[21:20] <Laurenceb> bu ti just dont know if two chutes is enough
[21:20] <Laurenceb> theres certainly no redundancy :P
[21:21] <Laurenceb> polythene chute at 240mph will be shredded and landing on the little nylon chute would leave things very smashed
[21:22] <shellevil> On that.
[21:23] <Laurenceb> ?
[21:23] <shellevil> I was designing for my UAV a computer board foamed inside a CF egg
[21:23] <Laurenceb> neat
[21:23] <shellevil> Inside a foamed outer structure
[21:24] <Laurenceb> fergusnoble: have you worked out where to put the antenna yet?
[21:24] <shellevil> s/CF/kevlar/
[21:25] <fergusnoble> Laurenceb: not completely, in the nosecone or by the side of the body with some kind of kevlar apature
[21:25] <Laurenceb> sounds very neat
[21:25] <Laurenceb> have you considered on the fins?
[21:26] <Laurenceb> i.e. a trailing ant
[21:26] <fergusnoble> Laurenceb: dont want to run a cable down there as the tube has to split
[21:26] <fergusnoble> and the flight computer needs to be up the nose end for stability
[21:26] <Laurenceb> for the chute?
[21:26] <fergusnoble> yeah, splits for the chute
[21:26] <Laurenceb> ok
[21:27] <Laurenceb> hmm I dont like the sound of that
[21:27] <Laurenceb> splitting at 240mph
[21:27] <fergusnoble> we can make part of the nose out of kevlar
[21:27] <Laurenceb> yeah
[21:27] <fergusnoble> Laurenceb: the current thinking is to have a supersonic retarder of some kind
[21:27] <Laurenceb> sounds heavy
[21:27] <fergusnoble> like solid flaps that deploy
[21:27] <Laurenceb> yeah sure
[21:28] <fergusnoble> yeah, nothing is fixed, but would be nice to have is slow down a bit more gently
[21:28] <Laurenceb> I'll try an do a quick sketch of what I was thinking
[21:29] <fergusnoble> I've come up with two designs for a retarder that should be quite light
[21:29] <Laurenceb> hows it deployed?
[21:29] <fergusnoble> one is flaps in the fins that once opened lock out without any complex mechanism
[21:29] <Laurenceb> neat
[21:29] <fergusnoble> deployed at apogee when there arent any forces on them
[21:30] <fergusnoble> and the pressure makes them more rigid once open
[21:30] <fergusnoble> the disadvantage there is that its more weight at the wrong end and if the gps antenna is near the nose it goes down gps antenna down
[21:31] <fergusnoble> also when deploying the chute the body gets yanked around through 180 degrees
[21:31] <Laurenceb> you could make an ant that'd still get some sats in that position
[21:33] <fergusnoble> the other design splits the nosecone and so you would fly down tail first, and also the parachute can come out backwards from the nose opening so the body isnt yanked when it opens
[21:33] <fergusnoble> but its hard to make that design so strong
[21:34] <fergusnoble> and there is a chance you dont have enough area in the nose to bring the CoP back enough so you actually do go down tail first
[21:35] Action: Laurenceb wishes the was a quick and easy way to draw graphics
[21:36] <shellevil> i've got a nice solution for that.
[21:36] <shellevil> Stack of post-it-notes, and a duct-taped webcam at optimal position to just take a pic of one.
[21:36] <shellevil> :/
[21:36] <Laurenceb> yeah
[21:37] <Laurenceb> infinately faster and better
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[21:41] <G8KHW> there aught to be a quick way of sharing files on here - like somthing you can drag and drop files on a web server and it gives you the URL to paste in
[21:42] <Laurenceb> http://imagebin.org/37560
[21:42] <G8KHW> drag and drop
[21:42] <G8KHW> ?
[21:42] <Laurenceb> ok the two red bits pop off the sides
[21:42] <Laurenceb> theres a nylon chute one side and polythene the other
[21:43] <Laurenceb> then theres some space for the blackfin ect down the middle
[21:43] <Laurenceb> there would need to be a thin plastic vacuum formed liner for the chutes to fit in
[21:43] <G8KHW> I have used imagebin befire - its not drag and drop though
[21:44] <Laurenceb> then maybe fill the tronics compartment with cyanoacrylate foam for extra strenght
[21:44] <G8KHW> ?
[21:44] <Laurenceb> no
[21:44] <Laurenceb> I'm not sure drag and drop is possible with a browser
[21:44] <Laurenceb> unless its using ftp
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[21:45] <shellevil> or flash
[21:45] <Laurenceb> you could make the red pop offs from something rf transparent
[21:45] <G8KHW> Laurenceb: I'm sure drag and drop is possible somehow - might need a windows app
[21:46] <Laurenceb> yeah
[21:46] <shellevil> or an integrated browser/desktop thingy
[21:46] <shellevil> konq?
[21:46] <Laurenceb> then your pop off section could help solve the radio downlink problem maybe
[21:47] <jcoxon> hey all
[21:47] <Laurenceb> hi
[21:49] <shellevil> hey
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[21:51] <jcoxon> managed to get some sort of resemblance to rtty yesterday with pwm on the arduino and a low pass filter
[21:51] <Laurenceb> jcoxon: I have code on the wiki
[21:52] <jcoxon> Laurenceb, yeah i saw
[21:52] <Laurenceb> you probably want a second order low pass filter
[21:52] <Laurenceb> bu tI'm moving to MFSK64 now
[21:52] <jcoxon> am going to play with some interrupt/pwm code
[21:53] <Laurenceb> anyone any good with python?
[21:54] <jcoxon> a little
[21:54] Action: shellevil once read a little bit of a tutorial :/
[21:54] <G8KHW> I know most of the sketches off by heart
[21:54] <Laurenceb> how do I turn a string into an int?
[21:54] <Laurenceb> e.g. "123"
[21:54] <Laurenceb> I tried just int(str)
[21:55] <Laurenceb> but its giving weird reults
[21:55] Action: shellevil needs to finish that. And VHDL. And insulation of house. And waterproofing of house. And launch of HAB. And UAV, and ...
[21:56] <fergusnoble> G8KHW: we could make a UKHAS dropbox
[21:56] <jcoxon> hmmm i int(x) should work
[21:56] <jcoxon> thought*
[21:57] <jcoxon> G8KHW, :-D
[21:57] <fergusnoble> G8KHW: i think it just come up like a folder and its synced to everyone who's conneced to it
[21:59] <fergusnoble> Laurenceb: i can do some python, what you trying to do?
[21:59] <fergusnoble> ill run your idea past iain, but it looks good to me
[22:00] <Laurenceb> make a load of hex for my MFSK generator
[22:00] <Laurenceb> fergus: the foam is so the pyros dont crush the thin liner in onto the tronics
[22:00] <fergusnoble> would need careful design if you want to pyro deploy the chutes
[22:00] <Laurenceb> yeah
[22:00] <fergusnoble> ok, cool
[22:00] <fergusnoble> just a load of random data?
[22:00] <Laurenceb> you could stick a lipo cell down the middle between the blackfin and badger say
[22:01] <fergusnoble> or specific HEX?
[22:01] <Laurenceb> kind of
[22:01] <Laurenceb> its to take something I ripped out of the docs and generate hex to load into my avr
[22:01] <G8KHW> fergusnoble: that would be just what I want - under windows?
[22:02] <Laurenceb> print "%04x\n" % acc shouldnt that print 4 characters?
[22:02] <fergusnoble> G8KHW: for windows, mac and linux
[22:02] <G8KHW> fergusnoble: that get my vote then
[22:03] <Laurenceb> http://pastebin.com/d3d03f121
[22:03] <fergusnoble> Laurenceb: that should do it
[22:04] <fergusnoble> although ive only used %x under C and not python
[22:04] <Laurenceb> its giving me 6 characters
[22:05] <Laurenceb> http://pastebin.com/d1553ac0d
[22:05] <Laurenceb> thats what I'm running iton
[22:06] <fergusnoble> just tried it here and i get 4 chars
[22:06] <Laurenceb> ok thanks
[22:06] <Laurenceb> this is pretty weird
[22:07] <fergusnoble> it gives me more chars if you give it a number thats more than 4 chars long in hex
[22:07] <Laurenceb> ah
[22:07] <Laurenceb> hmm I'll have to take a lok then
[22:09] <Laurenceb> oh accu=0
[22:09] <Laurenceb> nvm
[22:10] <Laurenceb> basically I have 256 two byte words in flash
[22:11] <Laurenceb> each one is a varicoded ascii char, the 4 msb are the number of valid bits in the varicode
[22:13] <fergusnoble> what do you mean by valid bits?
[22:14] <Laurenceb> as in are there 4 varicode bits, 6 , 8?
[22:14] <Laurenceb> how many bits are there in the varicode character
[22:24] <Laurenceb> hmm if (foundstring and m=='"'): isnt working
[22:24] <Laurenceb> its always false
[22:33] <jcoxon> scrap pwm, i've gone back to resistors on 2 pins for rtty
[22:35] <Laurenceb> hehe
[22:35] <Laurenceb> bbl
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[23:43] <Laurenceb> hi edmoore
[23:43] <edmoore> hi
[23:43] <Laurenceb> I'm liking the sound of the rocket
[23:43] <Laurenceb> need pics :P
[23:43] <edmoore> lol
[23:44] <edmoore> i think the autoclave will have to be fixed first
[23:44] <edmoore> thankfully someone in the department is stumping up the cash
[23:44] <Laurenceb> you avent finished the CF yet?
[23:44] <edmoore> it's quite iterative, CF
[23:44] <Laurenceb> ok
[23:45] <edmoore> you just keep doing it again and again, hopefully with better results each time after progressive tweaks in the technique
[23:45] <Laurenceb> ah you are trying several attempts?
[23:45] <SpeedEvil> where're you getting the prepreg?
[23:45] <edmoore> hexcel
[23:46] <Laurenceb> thats cool as you'll have lots left over to chuck off a cliff and test recovery with
[23:46] <SpeedEvil> Does it have to be kept frozen, or can it be shipped at room temp?
[23:46] <Laurenceb> :D
[23:46] <edmoore> Laurenceb: yes. Whilst I'm not the expert on CF working in the group by any means, I think I'm on firm ground when I say that each rocket gets a little better every try, and at some point we will have one we're happy to fly
[23:46] <edmoore> SpeedEvil: there's a big freezer
[23:46] <edmoore> and that's in an air-conditioned layup room
[23:47] <Laurenceb> its preimpregnated with resin?
[23:47] <SpeedEvil> yes
[23:47] <edmoore> rather than human embryos, yes
[23:47] <Laurenceb> oh I was thinking just polymer
[23:47] <Laurenceb> that melts
[23:48] <SpeedEvil> it's thermoset epoxy
[23:48] <SpeedEvil> (typically)
[23:48] <Laurenceb> neat
[23:49] <Laurenceb> is the dept paying for all this?
[23:56] <edmoore> sponsored
[23:56] <edmoore> ask people nicely. it works
[23:56] <SpeedEvil> you're in the right place too, which helps.
[23:57] <edmoore> yep, it's a 5 minute drive to hexcel
[23:57] <edmoore> they leave a roll of stuff by reception
[23:57] <SpeedEvil> I suppose they have some stuff that's almost out of date fairly often.
[23:57] <SpeedEvil> Or ends.
[23:59] <edmoore> i think it's mainly getting to the end of its shelf life. they're quite big rolls
[23:59] <edmoore> and nice stuff too - space rated often
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[00:00] --- Thu Feb 5 2009