well at least it didnt blow up. ¯\_(ツ)_/¯
SpaceX Dragon CRS-6 Launch Webcast
111–120 of 151 posts
Re: SpaceX Dragon CRS-6 Launch Webcast
#112T+17m: Not a successful landing today. That sucks. Source: http://www.reddit.com/r/spacex/comments/32jnyd/rspacex_crs6_... Edit: "Looks like Falcon landed fine, but excess lateral velocity caused it to tip over post landing" @elonmusk
There is an opportunity here for some clever control system design. If the mobile platform is brought into the control system loop, it can move to adjust for excess lateral velocity.
Won't be easy, but if anyone can do it, it's SpaceX.
Re: SpaceX Dragon CRS-6 Launch Webcast
#113Earlier quoted context omitted.
the original, yes. now they've got experience and say they've got 80% odds for landing one first stage by the end of the year.
How can that make sense? Until they actually get a successful landing they can't be sure they don't have a problem that causes a failure 100% of the time.
That's why it's a probability. Do you not understand how estimate work?
Re: SpaceX Dragon CRS-6 Launch Webcast
#114"Stage 1 has been saved"!!! Edit: Apparently it's not what I hoped, http://www.reddit.com/r/spacex/comments/2swnth/how_well_does... 'saved' and 'safed' are pretty similar on stream...
I don't think they said anything after "landing burn started". They like to milk news like that a bit.
It's about managing expectations. The landings are part of an experimental R&D program, they don't necessarily need constant coverage all the time, though it is exciting to follow the progress.
Re: SpaceX Dragon CRS-6 Launch Webcast
#115Earlier quoted context omitted.
Scott Manley did precisely this in KSP the other day, trying to replicate the barge landing: https://www.youtube.com/watch?v=C9I55o8hQgs Admittedly, he also replicated all the other possible failure modes too. Turns out landing on barges is hard.
I wonder how much of the rocket is steel? Perhaps a barge full of Tesla batteries and electromagnets could grab and hold it as it comes in?
It's almost entirely aluminum.
Re: SpaceX Dragon CRS-6 Launch Webcast
#116Earlier quoted context omitted.
How can that make sense? Until they actually get a successful landing they can't be sure they don't have a problem that causes a failure 100% of the time.
Musk is a mastermind/strategic/INTJ personality. Much of someone skill of someone like this it often from making assumptions based on hunches. It could just be a hunch. And that's totally fine.
As an INTJ, I'm curious why you mentioned that trait in such a sentence. Also, remember: everything you see around you, what you call the world, was built be people no smarter than you.
Re: SpaceX Dragon CRS-6 Launch Webcast
#117Earlier quoted context omitted.
Pretty standard Kerbal landing - vertical ok, but too much lateral.
Just have to put those legs on struts sticking out the sides to give it a wider base!
Just how bad is salt water for the engines? Cut a hole in the landing barge and hit that, with struts mounted 2/3 of the way up to catch on the sides of the hole.
Actually -- make the hole a steel cavity projecting below the waterline, with smooth sloped sides. Thus a miss hits the cavity side and the rocket slides down. Put thrusters at the top of the rocket to push against the pitch torque when the thing contacts the cavity. Drop your struts from the top of the rocket on to the barge.
Now you've got a lower center of mass and wider "legs". You will for sure bang up the side of the rocket, but so what, it is the engines that you really want to recover. (Hmm, actually it will be the rocket exhaust that hits the well first anyway, does pressure in the well from the rocket exhaust help at all? Might slow down the descent, might increase the pitch torque.)
Re: SpaceX Dragon CRS-6 Launch Webcast
#118T+17m: Not a successful landing today. That sucks. Source: http://www.reddit.com/r/spacex/comments/32jnyd/rspacex_crs6_... Edit: "Looks like Falcon landed fine, but excess lateral velocity caused it to tip over post landing" @elonmusk
There is an opportunity here for some clever control system design. If the mobile platform is brought into the control system loop, it can move to adjust for excess lateral velocity. Won't be easy, but if anyone can do it, it's SpaceX.
[deleted]
Re: SpaceX Dragon CRS-6 Launch Webcast
#119T+17m: Not a successful landing today. That sucks. Source: http://www.reddit.com/r/spacex/comments/32jnyd/rspacex_crs6_... Edit: "Looks like Falcon landed fine, but excess lateral velocity caused it to tip over post landing" @elonmusk
There is an opportunity here for some clever control system design. If the mobile platform is brought into the control system loop, it can move to adjust for excess lateral velocity. Won't be easy, but if anyone can do it, it's SpaceX.
This barge is in a turbulent ocean, so it's already doing a lot of work just to stay somewhat still. Plus the vision tracking on the rocket is already accounting for the movement of the barge.
Re: SpaceX Dragon CRS-6 Launch Webcast
#120Earlier quoted context omitted.
Still... you can't assign a probability to something that is, by definition, unknown. "This is just a complete guess..."
But you shouldn't also pretend you have zero information. They hit the barge last time, engineering principles are sound, so those two things alone give you an estimate of "quite likely". Yes, 80% is kind of arbitrary, but it tells you the same story as "quite likely" with an added benefit of being able to plug it into some math that will yield you better results than going with just words. See "If It’s Worth Doing,…
As a counterargument:
http://lesswrong.com/lw/sg/when_not_to_use_probabilities/
(Note that I think that starting with a good 50/50 coinflip and revising it based on evidence in this case is reasonable, I just think it's nice to have a reasoned opposing opinion sometimes.)