[amsat-bb] Re: Path to HEO

2013-09-05 Thread Samudra Haque
Hello, Perhaps my recent work may stimulate discussion in this thread, though it has not been proven in Space yet, but ... my George Washington University MAE dept. micropropulsion subsystems for small spacecraft was highlighted in the September 3 issue of the School of Engineering and Applied Sci

[amsat-bb] Re: Path to HEO

2013-09-05 Thread Robert McGwier
What is the specific Impulse? On Thursday, September 5, 2013, Samudra Haque wrote: > Hello, > Perhaps my recent work may stimulate discussion in this thread, though it > has not been proven in Space yet, but ... > > my George Washington University MAE dept. micropropulsion subsystems for > small

[amsat-bb] Re: Path to HEO

2013-05-03 Thread M5AKA
Can't remember if the links on the work of N1BCD were posted earlier: Video of presentation at http://www.ustream.tv/recorded/22959312/highlight/267762 Slides http://icubesat.files.wordpress.com/2012/06/icubesat-org-2012-c-1-1-_presentation_brandon_201205231623.pdf IARU Coordination http://ww

[amsat-bb] Re: Path to HEO

2013-05-02 Thread Patrick Strasser
schrieb Ken Ernandes on 2013-04-30 09:49: > I note the disclaimer at the bottom, so I'll help with the incorrect > assumptions. > > 1. g = 9.81 m/sec only applies to one Earth radius (i.e., the Earth's > surface). Gravitational acceleration drops of as an inverse square of the > radius. > 2.

[amsat-bb] Re: Path to HEO

2013-05-01 Thread Bryce Salmi
I'll throw this one out there though I'm sure some of you already know about it. "Rocket Propulsion Elements" is a pretty good book on the basics of rocket propulsion. I've dabbled in it a few times but do plan on a more comprehensive study (I'm an EE and actual coursework takes precedence over thi

[amsat-bb] Re: Path to HEO

2013-05-01 Thread JoAnne Maenpaa
> Then fire to the rear forcing the little satellite faster Yeah, but the control, er safety, folks won't give us enough "mass out the ass" to propel us forward ... can't have a clip with 30 pretty soon! -- 73 de JoAnne K9JKM ___ Sent via AMSAT-BB@ams

[amsat-bb] Re: Path to HEO

2013-05-01 Thread Bob- W7LRD
- Original Message - From: g0...@aol.com To: n...@mwt.net, glasbren...@mindspring.com, amsat-bb@amsat.org Sent: Tuesday, April 30, 2013 1:35:08 PM Subject: [amsat-bb] Re: Path to HEO Hi all. Deployable gain antennas are possible, but unfortunately attitude control is a real issue. If the orbit

[amsat-bb] Re: Path to HEO

2013-05-01 Thread Joe Leikhim
Thinking way outside the box, what about some sort of phased array using dipoles, which has the boresight synthesized to point at earth. In other words, don't use fuel to reorient the bird, electronically steer the phase of the antennas so that earth is in focus. -- Joe Leikhim Leikhim and A

[amsat-bb] Re: Path to HEO

2013-05-01 Thread M5AKA
--- On Tue, 30/4/13, Nick Pugh wrote: > Both Pumpkin and ISSIS say they have flight heritage on > 50 watt panels. EaLanta has rides to 600 KM 50 watts on a CubeSat ? That surprises me, I don't know of any that have flown so far that have generated more than about 6 watts of Solar Power. When y

[amsat-bb] Re: Path to HEO

2013-05-01 Thread M5AKA
--- On Tue, 30/4/13, g0...@aol.com wrote: > A compromise could be 4 Watts (ish) from MEO.  > Here's an oldie but goodie. http://www.g0mrf.com/MEOSAT.htm Yes MEO would be good. It should be possible to improve the signal levels while keeping omni-directional antennas on the satellite by us

[amsat-bb] Re: Path to HEO

2013-04-30 Thread Nick Pugh
If the solar panels are on 1 end that could be the back side of a patch antenna or reflectors for a Yagi. A 3U gives us about 12 inches in one plane. We will have reaction wheels to do pointing. Both Pumpkin and ISSIS say they have flight heritage on > 50 watt panels. EaLanta has rides to 600 KM an

[amsat-bb] Re: Path to HEO

2013-04-30 Thread g0mrf
0 Apr 2013 17:18 Subject: [amsat-bb] Re: Path to HEO On the Outside? :-) just like 90% of the earlier birds they are rolled or folded up until after deployment. IIRC: one of the first actually did use a rolled up tame measure for the elements. Joe WB9SBD Sig The Original Rolling Ball Clock Idle

[amsat-bb] Re: Path to HEO

2013-04-30 Thread Joe
On the Outside? :-) just like 90% of the earlier birds they are rolled or folded up until after deployment. IIRC: one of the first actually did use a rolled up tame measure for the elements. Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 4/3

[amsat-bb] Re: Path to HEO

2013-04-30 Thread M5AKA
--- On Tue, 30/4/13, Nick Pugh wrote: > From the comments HEO is challenging but doable. So let's > get started. But Nick it is already started, several groups have already developed CubeSat ion motors. The fact that, as far as I'm aware, none of the groups that have developed Ion Powered Cu

[amsat-bb] Re: Path to HEO

2013-04-30 Thread Andrew Glasbrenner
Where do the gain antennas go on a 10x10x30cm HEO? 73, Drew KO4MA Sent from my iPhone On Apr 30, 2013, at 9:01 AM, N0JY wrote: > I wonder about the amount of time spent in the Van Allen belts on the way up > there. We're concerned about radiation at a 650 km orbit, it might take some > heav

[amsat-bb] Re: Path to HEO

2013-04-30 Thread N0JY
I wonder about the amount of time spent in the Van Allen belts on the way up there. We're concerned about radiation at a 650 km orbit, it might take some heavy duty ($$) radiation tolerant components to survive a few years trip through the radiation belts as well as the final high orbit? Jer

[amsat-bb] Re: Path to HEO

2013-04-30 Thread M5AKA
--- On Tue, 30/4/13, Stefan Wagener wrote: > I like simple math. A 3U Cubesat can have deployable solar > cells which will give you between 45 and 70 watts of power. I made it at best a theoretical 15-20 watts from a 3U with deployable panels but having less solar power only extends the time it

[amsat-bb] Re: Path to HEO

2013-04-30 Thread Nick Pugh
-Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Patrick Strasser Sent: Monday, April 29, 2013 2:50 PM To: Amsat-bb@amsat.org Subject: [amsat-bb] Re: Path to HEO : In the end, it seems that changing from LEO to GEO or HEO is possible

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Stefan Wagener
Thanks, I like simple math. A 3U Cubesat can have deployable solar cells which will give you between 45 and 70 watts of power. That should drive an ion engine. Will need an active attitude control system and should start at the right orbit. Getting +-3kg to GTO is a $100.000? Don't know what the s

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Gus
On 04/29/2013 03:50 PM, Patrick Strasser wrote: Speed from radius and time for one orbit (1 day=84600 sec)... Uh, 86400 sec... But the difference isn't particularly significant. -- 73, de Gus 8P6SM Barbados, the easternmost isle. ___ Sent via AMSAT

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Patrick Strasser
schrieb Stefan Wagener on 2013-04-29 01:29: > LEO (low earth orbit) from 400 to 2000km or something like that > HEO (high earth orbit) >2km > > Going from 310 to 700km in a year is not doing us anything. We need a > highly elliptical orbit (Apogee ~6km, Perigee 900km) similar to AO-40 > t

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Joe Leikhim
Even if the technique required 5 years to advance to HEO it would be a positive step since the amateur launch opportunities directly to HEO are measured in decades and the cost in 10's millions of dollars. This reminds me of a commercial payload that failed to make GEO. The folks at AGI (STK S

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Burns Fisher
One thing that would seem to be a concern to me is how to keep the attitude steady while the ion engine is firing. Yes, not much thrust, but to make the most of it, you want it pointing in as close to the ideal direction as possible. I don't know how the various probes like Hayabusa and Dawn do i

[amsat-bb] Re: Path to HEO

2013-04-29 Thread M5AKA
--- On Mon, 29/4/13, Stefan Wagener wrote: > Thanks Bob, > That's why it is important to read the complete conversation. > This is NOT about Cubesats, staying in orbit, etc. It is about getting > into an HEO beyond 2km. It's the same thing, what gets you from 310 to 700 km can also get you t

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Robert Bruninga
> Going from 310 to 700km in a year is not doing us anything. Im not following this closely, but that statement misses the most important reason for doing this... *to*stay*in*orbit! The lifetime of a cubesat at 310km is only a few weeks at most. The life time at 700km is tens of years. The min

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Stefan Wagener
Thanks Bob, That's why it is important to read the complete conversation. This is NOT about Cubesats, staying in orbit, etc. It is about getting into an HEO beyond 2km. On Mon, Apr 29, 2013 at 1:34 PM, Robert Bruninga wrote: > > Going from 310 to 700km in a year is not doing us anything.

[amsat-bb] Re: Path to HEO

2013-04-29 Thread M5AKA
--- On Mon, 29/4/13, Stefan Wagener wrote: > maybe I didn't make myself clear: > LEO (low earth orbit) from 400 to 2000km or something like that > HEO (high earth orbit) >2km > Going from 310 to 700km in a year is not doing us anything. Romit-1 and the other CubeSats testing ion engines wil

[amsat-bb] Re: Path to HEO

2013-04-29 Thread Nick Pugh
fey [mailto:jamesduf...@comcast.net] Sent: Sunday, April 28, 2013 10:35 PM To: Franklin Antonio Cc: James Duffey; Nick Pugh; Amsat-bb@amsat.org Subject: Re: [amsat-bb] Re: Path to HEO Well I did a rough back of the envelope calculation for the time required to accumulate the energy necessary to get from LEO to

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Daniel Schultz
>In addition, doesn't the process getting from GTO to HEO require some form >of rapid acceleration? If yes, ion engines and solar sails are out. The main requirement for escaping from LEO is that the engine thrust must exceed the atmospheric drag force. The time required to reach a HEO orbit mainl

[amsat-bb] Re: Path to HEO

2013-04-28 Thread James Duffey
Well I did a rough back of the envelope calculation for the time required to accumulate the energy necessary to get from LEO to HEO, but there are a lot of details that still need to be calculated. And the devil is in the details. But this will get things started The difference in orbital energ

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Luc Leblanc
> Thanks, > > maybe I didn't make myself clear: > > LEO (low earth orbit) from 400 to 2000km or something like that > HEO (high earth orbit) >2km > > Going from 310 to 700km in a year is not doing us anything. We need a > highly elliptical orbit (Apogee ~6km, Perigee 900km) similar to

[amsat-bb] Re: Path to HEO

2013-04-28 Thread g0mrf
r the long passage through the radiation belts. Of course apogee 12000km and perigee 500km is a neat compromise. 73 David -Original Message- From: Stefan Wagener To: George and Cheryl Abbott CC: AMSAT BB Sent: Sun, 28 Apr 2013 21:16 Subject: [amsat-bb] Re: Path to HEO I always thoug

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Stefan Wagener
Thanks, maybe I didn't make myself clear: LEO (low earth orbit) from 400 to 2000km or something like that HEO (high earth orbit) >2km Going from 310 to 700km in a year is not doing us anything. We need a highly elliptical orbit (Apogee ~6km, Perigee 900km) similar to AO-40 to allow for c

[amsat-bb] Re: Path to HEO

2013-04-28 Thread M5AKA
--- On Sun, 28/4/13, Stefan Wagener wrote: > I always thought that to get to a suitable HEO you need to start at a > suitable GTO and not LEO. There's no reason why you couldn't go from a 310 km LEO orbit, it just takes time. Romit-1 is a 2U CubeSat developed by Euroluna volunteers. It has an i

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Franklin Antonio
At 11:14 AM 4/28/2013, Nick Pugh wrote: I have just returned from a satellite conference and I think new technology will now give us a path to HEO. I've thought for a long time that ion engines (small thrust pushing for a long time, powered by electricity) could be of great value to us. Has

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Stefan Wagener
ge, W1GMA.QTH about 20 south west of the Roger > Williams Park Zoo. > > -Original Message- From: Lizeth Norman > Sent: Sunday, April 28, 2013 2:35 PM > To: Nick Pugh > Cc: Amsat-bb@amsat.org > Subject: [amsat-bb] Re: Path to HEO > > > Sign me up. Sounds like the ne

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Joe Leikhim
Ditto; here, sounds like an promising direction. -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida jleik...@leikhim.com 407-982-0446 WWW.LEIKHIM.COM ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of

[amsat-bb] Re: Path to HEO

2013-04-28 Thread George and Cheryl Abbott
Great Job!73 to all. George, W1GMA.QTH about 20 south west of the Roger Williams Park Zoo. -Original Message- From: Lizeth Norman Sent: Sunday, April 28, 2013 2:35 PM To: Nick Pugh Cc: Amsat-bb@amsat.org Subject: [amsat-bb] Re: Path to HEO Sign me up. Sounds like the next big thing

[amsat-bb] Re: Path to HEO

2013-04-28 Thread Lizeth Norman
Sign me up. Sounds like the next big thing. 73 de Norm n3ykf On Sun, Apr 28, 2013 at 2:14 PM, Nick Pugh wrote: > I have just returned from a satellite conference and I think new technology > will now give us a path to HEO. Challenging of course but for the clever > doable. Please take a look at