RC India

General Topics => Chatter Zone => Topic started by: nchandra on May 18, 2014, 12:46:17 PM



Title: FPV from space ?
Post by: nchandra on May 18, 2014, 12:46:17 PM
https://www.youtube.com/watch?v=rpBnurznFio (http://www.youtube.com/watch?v=rpBnurznFio#ws)

This guys claim for FPV from edge of space. every thing is believable he use helium and float it to edge and glide it down back.

BUT he was also having live feed from craft and video quality was amazing maybe HD (he is using go pro). i can believe he had two camera one for feed and another go pro for just recording. But looking into the video it show he had lost feed which only prove showed video is the video feed moreover in comments somewhere its mentioned he had actually lost the craft as it was untraceable.

So can this be real? Can we really get that much range of 33km and HD quality using 1.2 GHz 1 watt video link using booster+yagi rec.? Cannot be sure that is 33km altitude also i think shown altitude is even higher. Moreover the craft will not drift kilometers from that height ? it had just drifted to another side of lake.

just want to know and believe this is possible and i will try some day.  (:|~


Title: Re: FPV from space, can this video be real ?
Post by: dhruvafreak on May 18, 2014, 03:16:16 PM
I saw this video and I guess its possible . I had doubts earlier but detailed explanation was given on a show on DISCOVERY CHANNEL.
So its Real :)


Title: Re: FPV from space ?
Post by: maahinberi on May 18, 2014, 03:43:59 PM
http://www.youtube.com/watch?v=uGeYNaCl6Go#ws (http://www.youtube.com/watch?v=uGeYNaCl6Go#ws)


Title: Re: FPV from space ?
Post by: maahinberi on May 18, 2014, 03:44:35 PM
http://www.youtube.com/watch?v=DQMi6Jk38g0#ws (http://www.youtube.com/watch?v=DQMi6Jk38g0#ws)


Title: Re: FPV from space ?
Post by: maahinberi on May 18, 2014, 03:45:02 PM
http://www.youtube.com/watch?v=emN3pxqkl68#ws (http://www.youtube.com/watch?v=emN3pxqkl68#ws)


Title: Re: FPV from space ?
Post by: SideWinder on May 18, 2014, 04:35:02 PM
People are able to get 20+ kms of range on 5.8ghz, 200mw Tx/Rx with custom antennas, so I think 33kms on 1.2ghz @ 1W with a Yagi antenna is possible. But since antennas would be highly directional, its important to point them correctly according to the position of your craft otherwise you will loose link.

Similarly using a 433mhz Radio Tx with high gain antenna will also give you control of your craft, but again you need to keep it pointed in the right direction. You can use a antenna tracker tho, however I wonder if GPS will work at such heights because most of them are programmed to work till 20kms of attitude.

Drift will depend on weather conditions, so its impossible to predict exactly where will your craft end up but you can till some extent. It can end right at the place you started but that would be a big coincidence and all factors working in favor for you  :)

Yes, its doable, but would require meticulous research and planning, and deeper pockets.





Title: Re: FPV from space ?
Post by: AnjanBabu on May 18, 2014, 05:25:58 PM
I actually proposed a similar idea at NASA's SpaceApps challenge for large scale missions to the ISS by balooning a rocket powered, low payload spacecraft to the edge of space and then propelling it into space, in an attempt to cut mission costs and mission deployment time. Some guys there told me it works against the purpose and is much more expensive then conventional liquid fuel rockets.

I decided to give it a try myself by dropping a rocket glider from my quad, to start with. ;D


Title: Re: FPV from space ?
Post by: utkarshg13 on May 18, 2014, 07:39:33 PM
In video it is told that some wire/connection broke on ground due to which he lost his reception. Further at a point when balloon was released it damaged the antenna. This video is a recording which is recorded through a Go pro most probably since video is of almost HD quality.
I tried to study on this. yes it is possible to get 33km range with the setup he is using.
Wonderful video.


Title: Re: FPV from space ?
Post by: roshan.dixit on May 18, 2014, 11:10:33 PM
Guys guys go pro records full hd 1080p even 4 k but hay its output through RCA cable is 320-480p you can not get a 1080p live feed as it would require really broad bandwidth frequency!!  You may be knowing that even Satellite Tv companies transmit 720p at most not at 1080p thats for sure!!


Title: Re: FPV from space ?
Post by: ujjwaana on May 19, 2014, 12:56:43 AM
A comprehensive  long range (Altitude and ground distance) records are maintained here :
http://fpvlab.com/forums/showthread.php?20039-Personal-Bests-V5-(LEARDERBOARDS) (http://fpvlab.com/forums/showthread.php?20039-Personal-Bests-V5-(LEARDERBOARDS))

it is not like Guinnies record and there could be better 'Amateur' records, but the list gives a fair idea what people can do with comodity off the shelf equipment. Imagine what Govt Agencies and Corporate can do with 100 to 100,000 times more budget. Its like School 'Jurassic Park' Home Video and Steven Spielberg's real epic flick.

I totally agree with Roshan on possibility of live transmission of HD content in such videos. Transmitting "Uncompressed" Video (as Roshan compared DTH 720p transmission, which is highly compressed using X.264 encoding) needs huge amount of Bandwidth. A typical VGA 640x480 "TV" quality transmission we use in FPV needs almost 5MHz for Video alone. 720p or 1080p would easily need 10 times more bandwidth than VGA.  Now designing that "Wide band" Video amplifier and pumping so much power to reach so far is a catch 22 situation: They cannot be compact and lower power consuming and powerful at the same time like our VGA Video Tx.
To prove my point, our Radio Controllers to control the planes use just 10mW to control same plane which is using more than 500mW-2watt to send video back. There are indeed HD Video Tx-Rx in the market, but they are too costly ($1500+) and very short range (200-300m) doe to Bandwidht and Power regulation on ISM/Free bands. Sports broadcasters use such system (like Spider Cam etc in IPL) but their gear are Multi-million dollar (The long Camera you see they take video of the Batsman in the crease cost more than 12 Crore each)


Such  FPV videos posted on Your tube are recorded  "On Board" on a SD card sitting inside HD Camera, while the Pilot flies with aid of VGA signal either fed from live VGA out of HeroHD/Mobious/Keychain/other Cam , or a separate CCD camera (more preferred) dedicated for FPV). The HD content is retrieved only when the plane lands and NOT live telecast.

I know there would be many budding FPV pilots in our RC community, but my humble request is that PLEASE AVOID flying FPV in sensitive area like Army installation, VIP area, Airports Railway station etc. Even a Nitro or gasser plane without any payload - Camera,Dropping (flower, but it could be explosive too) could easily proved as a hobby as non intrusive. But the moment you put a Camera, it becomes a Spying device.

There is a thin, VERY THIN line between having fun on weekend and become a news for others for a weekend. The entire RC hobby has got into bad press in the US in just these 4-5 years of Drone/FPV that it did not get in the last 60 years. The recent Quadrotor crash in Manhattan has created a furor. Imagine, they have a very functional and Potent AMA to fight for them with their own lawers. With bodies like AMAI (whose charter disowns any drone or FPV), we would be a great threat to the entire hobby in the country.

Be safe and fly safer.


Title: Re: FPV from space ?
Post by: essaargee on May 19, 2014, 08:13:37 AM
 :) I entirely concur with Ujjwaana. As they say, all is well that ends well >:D but once something goes wrong, the goose is cooked :o. Then it may be very difficult to undo the damage done, to a fragile and unorganized / loosely organized Bodies like ours in India, with no muscle and/or money. Tasting and enjoying the soup is an entirely different proposition than to get in to soup. Even within my very limited exposure and experience in the hobby, I have seen quite a few tricky situations (not necessarily my own) which COULD have turned ugly, but thank God, they did not.
One may argue : "How can we progress unless we are a little adventurous or zealous in the hobby?". But please, at the same time keep the interests of Self/ the Organization / Hobby in your perspective and be responsible. Can we afford the risk / adventure individually or as a Body :Rs: :Rs: :help: :help: :-\ :-\ :headscratch:?
This reminds me of an incident that took place recently. One of our relations - a lady with parents, in-laws, hubby, two kids and a job - came here (now I am in Brisbane for sometime) to do scuba diving and sky diving 8-). In-laws and hubby were with her. When the adventure proposal was put forward :P, the in-laws were vehemently opposed to it. The argument went to the extent that the lady was accused of behaving irresponsibly and what would happen if something goes wrong >:(. In the end, the lady won over the debate, finished her divings (both scuba and sky) uneventfully  :bow: and returned home India. All happy and content :thumbsup:.
The points now raised here in our hobby lobby reminded me of the debate that took place here about the adventure - how very valid, indeed!!! But now that nothing bad happened, all good and happy !!!
THAT is the thin line, the VERY THIN LINE noted by Ujjwaana, that is to be kept in mind. Sorry I veered away from the technical aspect. 
Pardon me if I have raised some ones hackles...


Title: Re: FPV from space ?
Post by: roshan.dixit on May 19, 2014, 12:42:25 PM
Thank you Ujjwaana  for supporting my views .. I would also like to tell you that- Why did David wanted his GOPRO back because he wanted the HD FOOTAGE!! We are talking about people who destroy go - proz which is of around 300-400$ so use your common sense!! To transmit live HD feed just about 100 meters the transmitter costs 20000 to be exact which is used by people who use  wire free led tvs!! 


Title: Re: FPV from space ?
Post by: SideWinder on May 19, 2014, 02:48:55 PM
Yes, HD/Full HD is not possible on standard fpv systems, I missed that part of OP's question. 

There are kits available in public domain such as DJI Lightbridge with claims 5kms of range with 14dbi patch antenna @1399$ . Building more directional antennas should help to increase range but dont think its gonna get anywhere near what we can with our FPV systems. And again it would be highly compressed with latency.
http://www.getfpv.com/dji-lightbridge-2-4ghz-full-hd-video-downlink.html (http://www.getfpv.com/dji-lightbridge-2-4ghz-full-hd-video-downlink.html)

And Tata Sky does broadcast video at 1080i and I believe many other broadcasters do, otherwise many of them are cheating customers, atleast Tata Sky would be.


Title: Re: FPV from space ?
Post by: roshan.dixit on May 19, 2014, 07:49:12 PM
All Satellite Tv companies transmit 720p!!


Title: Re: FPV from space ?
Post by: SideWinder on May 19, 2014, 09:34:45 PM
Its clearly stated on Tata Sky's website that they transmit in 1080i(different than 1080p). And I know that because Im using the service on on a full HD Tv and I can say that its full HD at low bitrate i.e huge amount of compression at play but resolution is 1080i.

http://www.tatasky.com/wps/portal/tatasky/tataskyhd/whatishd (http://www.tatasky.com/wps/portal/tatasky/tataskyhd/whatishd)

If you can prove otherwise, we can or atleast I will follow that up with them.


Title: Re: FPV from space ?
Post by: roshan.dixit on May 20, 2014, 09:23:15 AM
Hahaha 1080i Is HD READY NOT FULL HD 1080P IS FULLHD I also use Tata sky HD along with Dish Tv hd both output is 720p or 1080i HD READY not full hd!!


Title: Re: FPV from space ?
Post by: topalle on May 20, 2014, 09:55:17 AM
Yesterday afternoon it was shown on Discovery channel at 1 PM


Title: Re: FPV from space ?
Post by: SideWinder on May 20, 2014, 01:26:12 PM
Hahaha 1080i Is HD READY NOT FULL HD 1080P IS FULLHD I also use Tata sky HD along with Dish Tv hd both output is 720p or 1080i HD READY not full hd!!
You got me there, I should have said HD.Yet comparatively 1080i has higher pixel count and provides higher resolution than 720p at slower frame rates. Similarly 1080i as well as 1080p have same pixel count(can read more about the calculations below) and from the perspective of a viewer , he wont find a big difference between them.
Furthermore 720p,1080i and 1080p are classified under "HD". And HD READY is a term used for screens which are capable of displaying "HD". But different manufacturers to differentiate there products use the term "full HD" or "HD READY 1080p" for 1080p to use it as a selling point against 720p screens.

http://www.cnet.com/how-to/1080i-and-1080p-are-the-same-resolution/ (http://www.cnet.com/how-to/1080i-and-1080p-are-the-same-resolution/)
http://en.wikipedia.org/wiki/HD_ready (http://en.wikipedia.org/wiki/HD_ready)
http://en.wikipedia.org/wiki/High-definition_television (http://en.wikipedia.org/wiki/High-definition_television)

All Satellite Tv companies transmit 720p!!
And satellite companies do transmit in 1080i which you didn't seem to agree earlier??

And I will let you have the last word ,which Im sure you would like to. Cant be bothered  8-)