From 10 km to 10 m... oh dear. This is three orders of magnitude.
With the grid fins, they believe they can take care of the 10 km, and then it's back to GH land.So it's not like some mechanism has to improve by x1000
Quote from: meekGee on 12/17/2014 03:39 pmWith the grid fins, they believe they can take care of the 10 km, and then it's back to GH land.So it's not like some mechanism has to improve by x1000I fully agree. But it would not be surprising or a problem if they need to take lessons from the first try to succeed on second try. We can certainly hope for success this time but have no reason to worry if it does not work.
Hey - can anyone here identify the comm equipment visible in the SpaceFlightNow images?I spot a few domes that look to me like housing for radar equipment (they are also on the tubs), and one gimballed dish, (maybe 3' across?) that looks to be on the Go Quest.Actually, the barge has two of the domes, one of each end. Could this be related to the GPS system? A dGPS base station? I wonder if we can find such a dome at McGregor.
A dGPS base station?
From spaceflightnow.com photograph. We can see one of the thrusters ?
Quote from: meekGee on 12/17/2014 04:00 pmHey - can anyone here identify the comm equipment visible in the SpaceFlightNow images?I spot a few domes that look to me like housing for radar equipment (they are also on the tubs), and one gimballed dish, (maybe 3' across?) that looks to be on the Go Quest.Actually, the barge has two of the domes, one of each end. Could this be related to the GPS system? A dGPS base station? I wonder if we can find such a dome at McGregor.Yes, this is one of the domes on the deck of Go Quest:http://www.cobham.com/media/967931/sailor_900_vsat_product_sheet.pdfIt's a stabilized VSAT (very small sperture terminal) antenna for Ku-band satellite broadband, with integrated GPS.http://en.m.wikipedia.org/wiki/Very-small-aperture_terminalAnd this appears to be one of the domes on the ASDS:http://www.kvh.com/Commercial-and-OEM/Maritime-Systems/Communications/mini-VSAT-Broadband/TracPhone-V11IP.aspxhttp://www.marinelink.com/news/transmit-weather-data370307.aspxYou can see the KVH VSAT dome in the SFN photo of the Elsbeth III pushing the ASDS. The dome is atop the tan container, just to the left of the Elsbeth III.
I spot a few domes that look to me like housing for radar equipment (they are also on the tubs), and one gimballed dish, (maybe 3' across?) that looks to be on the Go Quest.
Actually, the barge has two of the domes, one of each end.
Maybe that's directionality related? If there's no high point and you want to watch the forward direction of travel maybe you have 2?
But can it be used to get a precise determination of the relative distance vector to the moving base station? So it won't help you know where you are in an absolute coordinate system, but will give you a good reading of where you are in the barge's coordinate system?
..bit-rate wise, I think even 0.25 MBps can do wonders if you're willing to encode the file and not stream it (thus incurring a 20-30 second delay). For that matter, drop the frame rate, drop the resolution, until it goes through. I'm not expecting 3D HD TV in real time. Make it B&W. I'll still tune in...
..., and since the barge was purpose-built it seems likely that they'd use two of the same model.Those will both likely be streaming video from the onboard cameras back to Hawthorne.
Quote from: meekGee on 12/17/2014 05:45 pmBut can it be used to get a precise determination of the relative distance vector to the moving base station? So it won't help you know where you are in an absolute coordinate system, but will give you a good reading of where you are in the barge's coordinate system? No, because GPS is absolute and dGPS is just a refinement of the absolute location. The location of the dGPS transmitter is known and so it broadcasts the difference between its known position and what the GPS constellation says it is. This is then used to reduce the absolute error.
Quote from: meekGee on 12/17/2014 06:10 pm..bit-rate wise, I think even 0.25 MBps can do wonders if you're willing to encode the file and not stream it (thus incurring a 20-30 second delay). For that matter, drop the frame rate, drop the resolution, until it goes through. I'm not expecting 3D HD TV in real time. Make it B&W. I'll still tune in...Quote from: Kabloona on 12/17/2014 06:12 pm..., and since the barge was purpose-built it seems likely that they'd use two of the same model.Those will both likely be streaming video from the onboard cameras back to Hawthorne. I would love to watch this event real-time or near realtime. But I doubt they are counting on getting the maximum possible throughput from their uplinks as that would be a bad assumption. I would dedicate redundant resources to the telemetry, not the video. Frankly, I wouldn't dedicate anything to the video. I'd store it on multiple SSDs on the barge.But that's me and hopefully I'm wrong.
Quote from: mme on 12/17/2014 08:17 pm...I would love to watch this event real-time or near realtime. But I doubt they are counting on getting the maximum possible throughput from their uplinks as that would be a bad assumption. I would dedicate redundant resources to the telemetry, not the video. Frankly, I wouldn't dedicate anything to the video. I'd store it on multiple SSDs on the barge.But that's me and hopefully I'm wrong.That's true for getting data off the rocket, but unless you worry about the barge sinking, everything can be stored on the barge (including high rez video) and downloaded 5 minutes later.Rocket-originated video, I agree. Get the telemetry first. But that's a direct link at close range, no satellites involved.
...I would love to watch this event real-time or near realtime. But I doubt they are counting on getting the maximum possible throughput from their uplinks as that would be a bad assumption. I would dedicate redundant resources to the telemetry, not the video. Frankly, I wouldn't dedicate anything to the video. I'd store it on multiple SSDs on the barge.But that's me and hopefully I'm wrong.