highaltitude.log.20061025

[00:06] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: "Leaving"
[01:37] _kc0wys (n=kc0wys@24-107-152-228.dhcp.stls.mo.charter.com) joined #highaltitude.
[01:37] kc0wys (n=kc0wys@24-107-152-228.dhcp.stls.mo.charter.com) left irc: Read error: 104 (Connection reset by peer)
[05:05] d123 (n=jean@modemcable121.179-37-24.mc.videotron.ca) joined #highaltitude.
[05:06] Action: icez beeps
[05:06] <d123> morning
[05:11] <icez> not yet here (:
[05:11] <d123> in UK you mean?
[05:12] <icez> nah
[05:12] <icez> in the western US
[05:12] <d123> :)
[05:12] <icez> we don't really have cool groups of HAB amateurs like this one in the US :)
[05:13] <d123> nor in canada
[05:13] <d123> :)
[05:13] <icez> you're in canada?
[05:14] <d123> yes, quebec
[05:14] <d123> Montreal
[05:14] <icez> mmm
[05:14] <icez> it's morning there already?
[05:14] <d123> nope it's 0:14
[05:14] <icez> aww
[05:14] <d123> but in uk it's like 5 AM ;)
[05:14] <icez> tu parle francais?:)
[05:14] <d123> oui
[05:14] Action: icez vien du quebec
[05:14] <d123> :)
[05:14] <d123> no way
[05:14] <d123> where from?
[05:15] <icez> montreal:)
[05:15] <d123> sweet
[05:15] <d123> what made you move to the US?
[05:15] <d123> better job?
[05:16] <icez> parents divorced and my dad moved here (had to follow:P)
[05:16] <d123> if I'm not stepping on any toes with my question
[05:16] <d123> I see
[05:17] <d123> any skydivers in here?
[05:17] <icez> so you're interested in balloons?
[05:17] <icez> never tried
[05:17] <d123> mostly canopy
[05:17] <d123> but balloons are fun too
[05:19] <d123> are you lanching balloons?
[05:19] <icez> nope
[05:19] <icez> i'm a rocket person living in a place where rockets are pretty much illegal
[05:19] <icez> :/
[05:19] <d123> :(
[05:20] <d123> have you launched any rockets?
[05:28] <icez> did before
[05:29] <icez> first two were "pre-made"
[05:29] <icez> then i made one but the top was too heavy
[05:29] <icez> i made 2 tiny ones launch simultaneously but they both blew up in pieces :P
[05:32] <d123> What's the altitude peak for all your experiments?
[05:40] <icez> mmm
[05:40] <icez> (sorry was doing a 'digicam 101' for my stepmom :P)
[05:40] <icez> well...i'm not sure
[05:40] <icez> didn
[05:40] <icez> didn't have sensors on them
[05:49] <d123> I see, anyhow was very nice meeting you and caliss come and visit quebec again. We got good poutine ostie. I got to catch some sleep but I'll be back tomorrow tabarnak. Hope you still remember the quebec slangs :) Have a nice one dude.
[05:52] <icez> poutine
[05:52] <icez> i miss that stuff so much:(
[05:52] <d123> :D
[05:52] <icez> a demain;)
[05:52] <icez> sti.
[05:52] <icez> :P
[05:52] <d123> :D
[05:52] <d123> Joual
[07:20] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: Remote closed the connection
[08:51] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) joined #highaltitude.
[14:03] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[15:31] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: Remote closed the connection
[18:15] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[18:34] rocketboy (n=steve@217.47.75.184) joined #highaltitude.
[18:40] <jcoxon> hey rocketboy
[19:21] <rocketboy> hi jcoxon - hows it going
[19:23] <jcoxon> hey, its going well
[19:23] <jcoxon> how about you?
[19:23] <rocketboy> yeah - not so bad
[19:23] <rocketboy> I havn't made much progress with a HAB yet :-(
[19:24] <jcoxon> know the feeling
[19:24] <rocketboy> having decided to go down the PIC micro route I have been waiting for a In Circuit De-bugger
[19:24] <jcoxon> pegasus is hibinating right now
[19:24] <rocketboy> ah - I wondered
[19:25] <jcoxon> i'm sort of lacking inspiration
[19:25] <jcoxon> and a time
[19:25] <rocketboy> I see - what was your next flight going to do?
[19:25] <jcoxon> (though i found out how to use the 4 adcs on my gumstix today)
[19:26] <jcoxon> basically a better camera and some sensors
[19:26] <rocketboy> ah thats way cool - lots of things to plug in to those - what resolution are they?
[19:27] <jcoxon> 10-bit
[19:27] <jcoxon> i also know how to run servos as well (thanks to nomad)
[19:27] <rocketboy> - fair enough for almost all applications - what sensors? temp/volt/pressure/magnetic?
[19:28] <jcoxon> not sure!
[19:28] <jcoxon> i also have an i2c compass running
[19:28] <jcoxon> so actually i've made some progress
[19:28] <rocketboy> How didd the servos go - I got one myself
[19:28] <rocketboy> just for experimenatation
[19:29] <rocketboy> seem simple enought to drive - just PWM
[19:29] <jcoxon> did you see my Nomad autonomous buggy?
[19:29] <jcoxon> http://www.pegasushabproject.org.uk/nomad/
[19:29] <jcoxon> yeah but i can now generate through linux on any gpio
[19:29] <rocketboy> yeah - did you get it to work?
[19:29] <jcoxon> yes/no
[19:29] <jcoxon> it worked fine
[19:29] <jcoxon> but hte pathfinding wasn't very good :-D
[19:29] <jcoxon> just based on gps which isn't enough
[19:30] <jcoxon> i'm helping out with nova at the mo
[19:30] <rocketboy> yeah I gessed that for a buggy - but I think it would be OK for a HAB glider
[19:31] <rocketboy> - how they doing - carl phoned up last week to say the launch was put back a couple of weeks
[19:31] <jcoxon> yeah its seems to be going okay
[19:31] <jcoxon> the plan is for nov 4th
[19:32] <jcoxon> got quite a large team now
[19:32] <jcoxon> they are planning to run some battery experiments
[19:32] <jcoxon> definite direction is towards Henry's rockoon
[19:32] <rocketboy> excellent - I guess all the press coverage has helped
[19:33] <rocketboy> well its going to be difficult - but they are smart guys
[19:33] <jcoxon> yeah
[19:34] <jcoxon> i also think the summer has made them become v. realistic timing etc
[19:34] <rocketboy> I still think the stabilization at that altitude will be the problem
[19:34] <jcoxon> there should be an "about" in there
[19:34] <jcoxon> realistic about timing
[19:34] <jcoxon> yeah something about high velocity spinning
[19:34] <rocketboy> yeah its a big project
[19:35] <rocketboy> I did some cacualtions on spinnging a year or so ago - you need quite a speed
[19:36] <rocketboy> the rifeling on artillary shells gives some idea
[19:36] <rocketboy> I think i calcualted 15,000 RPM
[19:36] <jcoxon> wow
[19:37] <rocketboy> I might be wrong - but the small diameters drive a fast speed
[19:37] <jcoxon> right
[19:38] <rocketboy> also I think you need somthing to spin "against" otherwise the launch table will just spin - somthing like a reaction wheel
[19:39] <jcoxon> there are some designs on their wiki
[19:39] <rocketboy> like they use in satellites for positioning (rotating) them
[19:39] <rocketboy> I didn't know they had a wiki
[19:40] <jcoxon> hmmm i think its a closed wiki
[19:40] <jcoxon> yup it needs a password
[19:41] <jcoxon> next time i see carl - i'll get him to add you to the list
[19:41] <jcoxon> if you want
[19:41] <rocketboy> please
[19:42] <rocketboy> personally I'd be going for vectoring the motor - or gas jets
[19:42] <rocketboy> or javatar
[19:43] <jcoxon> a javatar?
[19:44] <jcoxon> (i think you've explained one to me before but i can't remember)
[19:44] <rocketboy> its like a small tube that fits round the exit of the rocket motor - and then you angle it to
[19:44] <rocketboy> vector the thrust
[19:45] <jcoxon> oh okay
[19:45] <rocketboy> one of my rocket mates has produced a working system useing a vectored rocket motor - and RC servos
[19:45] <jcoxon> would this be for hte rocket itself or the launch platform?
[19:45] <rocketboy> - he has had it hovering a few times - way cool
[19:46] <rocketboy> for the rocket
[19:46] <jcoxon> oh wow
[19:46] Action: jcoxon is beginning to think of ideas for servos and high altitudes
[19:46] <rocketboy> I think I have a video somewhere
[19:48] <rocketboy> there is also a rocket design with servos an canard fins (small fins about half way up the rocket) - these are driven from RC servos - I think the guy managed to get it to sun-seek
[19:49] <rocketboy> not any good for altitude - but demonstartes RC servos are fast enough
[19:50] <jcoxon> yeah
[19:53] ehj20 (n=ed@ehjones.plus.com) joined #highaltitude.
[19:54] <jcoxon> hey ehj20
[19:54] <jcoxon> hey d123, welcome to #highaltitude
[19:56] <jcoxon> might use a servo to rotate the camera
[19:56] <jcoxon> either in contrast to the spin of the payload (from the i2c dig compass)
[19:57] <jcoxon> so that the image is stable
[19:57] <jcoxon> or using the sensors to direct at something
[19:58] <rocketboy> have you thought about reaction wheels to stabilize?
[19:58] <jcoxon> not really
[19:58] <jcoxon> (literally just thought about it)
[20:00] <d123> hey guys thanks for the welcome and it's good to be here
[20:00] <rocketboy> - You could probably convert a old disk drive - I should think they have bearings good enough
[20:01] <jcoxon> rocketboy, so basically by spinning it up i can control the angle of hte payload?
[20:01] <jcoxon> d123, you planning any highaltitude projects?
[20:01] <rocketboy> - you need 2
[20:01] <rocketboy> to get 2 dimensional control
[20:01] <ehj20> hiya
[20:02] <rocketboy> hi guys
[20:03] <rocketboy> - as you spin them up the payload trists the other way
[20:03] <rocketboy> twists
[20:04] <jcoxon> so could you use one to counter the spin of hte payload
[20:04] <jcoxon> if it could spin either way
[20:04] <jcoxon> or do they need to spinning at constantly?
[20:05] <rocketboy> they normally spin constantly - and you accelerate/decelerate them to get the twist
[20:06] <rocketboy> and then bring them back to a stable speed
[20:06] <jcoxon> right
[20:07] <rocketboy> its all about the reaction of changing speed
[20:07] <rocketboy> (hence "reaction wheels")
[20:07] <jcoxon> so some simple software using the i2c compass to detect spin (it it works) could then vary the speed of the wheel to counter the natural spin :-)
[20:07] <rocketboy> yep
[20:08] <rocketboy> that is how they stabilize satellites
[20:08] <rocketboy> well one of the ways
[20:08] <jcoxon> hehe, i love the way that sounds easy
[20:09] <rocketboy> yeah - should be easy - just need a reference (compass) and a feedback loop to motor speed
[20:09] <rocketboy> weel - i'm sure its a lot more complicated really
[20:09] <jcoxon> hehe
[20:10] Action: jcoxon is beginning to feel inspired again
[20:10] <rocketboy> excellent
[20:10] Action: jcoxon hasn't got time till christmas :-(
[20:10] <rocketboy> uni I guess?
[20:11] <jcoxon> yeah - got to do some work as i graduate this year
[20:11] <jcoxon> i didn't bring my balloon stuff on purpose
[20:11] <rocketboy> * sounds like a ggood idea
[20:11] <jcoxon> however i can still plan
[20:11] <rocketboy> yeah
[20:12] <rocketboy> scheme and plot - thats my motto
[20:12] <jcoxon> indeed
[20:12] <rocketboy> - back in a few mins - i need to load the dishwasher
[20:22] <ehj20> I can see how a reaction wheel works well in a satellite, but not sure it'd be effective in a balloon. A satellite is under near-zero rotational forces, so only small reactionary forces are required. A balloon (probably?) suffers greater, and more unpredictable forces. In addition a reactionary wheels probably wouldn't be able to cope with a constant external rotational force?
[20:23] <ehj20> Whoops, sorry for the poor grammar. It's been a long day!
[20:24] <jcoxon> i sort of feel thats its worth a try
[20:24] <jcoxon> though we should be getting some spin data back from nova 2 in less then 2 weeks
[20:25] <ehj20> I don't mean it's not worth trying, just playing devil's advocate
[20:25] <jcoxon> oh i know :-p
[20:26] <jcoxon> i get the feeling that the ultimate situation would be a stabalised platform
[20:26] <jcoxon> for launching rockets etc
[20:27] <jcoxon> in the jet stream it would certainly have issues but once in the stratosphere if its calm it would be interesting
[20:27] <jcoxon> especially at less then 1% atmos
[20:27] <ehj20> Also I can imagine that the forces on a balloon aren't all that great all of the time, but once a cyclical (sp?) roation gets set up it carries on for a long time. In that case a reactionary wheel might damp the osscilations quite well.
[20:27] <d123> jcoxon: I'm more into skydiving right now but I'm considering doing some balloons launch with some friends. It's more of a far away in time project.
[20:27] <rocketboy> Well if the forces come and go the motors will just speed up and slow down the real issue is a constant spin force - like that from the twine to the payload
[20:29] <rocketboy> that just causes the motors to spin faster and faster
[20:29] <ehj20> Do you think the rotations oscillate, or does the whole lot, including balloon spin?
[20:29] <jcoxon> d123, cool - well the channel is often quiet but do get involved in hte converstation - skydiving knowledge would be a great assest
[20:30] <jcoxon> ehj20, the balloon certainly rotates at low altitudes - i've seen it happen
[20:30] <d123> thanks again, mate :)
[20:30] <rocketboy> I don't know for sure - But I imagine its an oscillaton - possibly with the exception of a twisting twine
[20:31] <jcoxon> rocketboy, is the reaction wheel positioned offcentre?
[20:31] <ehj20> I can imagine a twisting balloon with an oscillating payload beneath it. a pretty complex system to dampen :-)
[20:31] <rocketboy> - I imagine you need to place them at the centre of gravetty
[20:31] <jcoxon> oh and reactionwheels have been used at 80,000ft before for balloon borne telescopes
[20:32] <rocketboy> ah - a pretty good indication they work
[20:33] <jcoxon> i guess peg IV would be a smaller payload as well (not sure what difference that makes!)
[20:34] <ehj20> The smaller and lighter payload mass the better I'd have thought?
[20:36] <rocketboy> I was thinking disk drives - like an old 2.5" laptop drive
[20:42] <jcoxon> brb
[20:50] <jcoxon> hmmmm
[20:51] <rocketboy> jcoxon - I sent you an email with a video of that stabilized rocket in it
[20:51] <rocketboy> about 1.5mbytes
[20:52] <jcoxon> yeah just watched it
[20:52] <jcoxon> v. v. cool
[20:52] <rocketboy> yeah - I was there - amazing
[20:53] <jcoxon> i'm sure henry would be interested
[20:53] <rocketboy> sure - i'll drop him a line
[21:27] <jcoxon> night all
[21:27] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: "Leaving"
[21:40] rocketboy (n=steve@217.47.75.184) left irc: "Leaving"
[22:12] ehj20 (n=ed@ehjones.plus.com) left irc: "Leaving"
[23:47] _kc0wys (n=kc0wys@24-107-152-228.dhcp.stls.mo.charter.com) left irc:
[00:00] --- Thu Oct 26 2006