Quote from: Robotbeat on 08/29/2016 05:13 pmQuote from: SWGlassPit on 08/29/2016 04:11 pmQuote from: Robotbeat on 08/29/2016 03:28 pmDragon already contains strain gauges. Getting shot by a bullet should be detectable without 500lbs of wiring.Sure, if you hit really close to a strain gauge and do a lot of damage. Otherwise, they're useless for this....If a huge MMOD hit Dragon, enough to fatally damage it, it would ring like a bell, like getting shot be a gun. You would hear it, and sound waves can be (and are) picked up by strain gauges. It may not be precise, but knowing that it happened would be useful info.If a huge MMOD (hint: what does the first M stand for?)
Quote from: SWGlassPit on 08/29/2016 04:11 pmQuote from: Robotbeat on 08/29/2016 03:28 pmDragon already contains strain gauges. Getting shot by a bullet should be detectable without 500lbs of wiring.Sure, if you hit really close to a strain gauge and do a lot of damage. Otherwise, they're useless for this....If a huge MMOD hit Dragon, enough to fatally damage it, it would ring like a bell, like getting shot be a gun. You would hear it, and sound waves can be (and are) picked up by strain gauges. It may not be precise, but knowing that it happened would be useful info.
Quote from: Robotbeat on 08/29/2016 03:28 pmDragon already contains strain gauges. Getting shot by a bullet should be detectable without 500lbs of wiring.Sure, if you hit really close to a strain gauge and do a lot of damage. Otherwise, they're useless for this....
Dragon already contains strain gauges. Getting shot by a bullet should be detectable without 500lbs of wiring.
That was used for ascent purposes and was designed [...]
your mass budget is much better spent making the vehicle itself less vulnerable to damage than it is trying to pinpoint where it did get hit.
Quote from: SWGlassPit on 08/29/2016 04:11 pmDid you read the minutes? NASA wants the requirement to be met without requiring inspection.I got that. Are you saying, NASA won't agree to inspections when they know, there is something wrong? Just insisting it is the sole problem of the contractor? Seriously?
Did you read the minutes? NASA wants the requirement to be met without requiring inspection.
Quote from: guckyfan on 08/29/2016 05:31 pmQuote from: SWGlassPit on 08/29/2016 04:11 pmDid you read the minutes? NASA wants the requirement to be met without requiring inspection.I got that. Are you saying, NASA won't agree to inspections when they know, there is something wrong? Just insisting it is the sole problem of the contractor? Seriously?I'm almost positive that they'll do inspections anyway. The inspections, however, can't be part of the path to meeting requirements. The vehicles have to do that by themselves.
Quote from: SWGlassPit on 08/29/2016 05:11 pmThat was used for ascent purposes and was designed [...]That's a lot of words rather than just admitting you're wrong. That doesn't mean it was perfect or even worthwhile, but a spacecraft has indeed used such a system.
Quote from: SWGlassPit on 08/29/2016 05:34 pmQuote from: guckyfan on 08/29/2016 05:31 pmQuote from: SWGlassPit on 08/29/2016 04:11 pmDid you read the minutes? NASA wants the requirement to be met without requiring inspection.I got that. Are you saying, NASA won't agree to inspections when they know, there is something wrong? Just insisting it is the sole problem of the contractor? Seriously?I'm almost positive that they'll do inspections anyway. The inspections, however, can't be part of the path to meeting requirements. The vehicles have to do that by themselves.So in other words, compound conservatism. Sounds like a good recipe to increase overall costs.
Quote from: Robotbeat on 08/29/2016 05:13 pmQuote from: SWGlassPit on 08/29/2016 04:11 pmQuote from: Robotbeat on 08/29/2016 03:28 pmDragon already contains strain gauges. Getting shot by a bullet should be detectable without 500lbs of wiring.Sure, if you hit really close to a strain gauge and do a lot of damage. Otherwise, they're useless for this....If a huge MMOD hit Dragon, enough to fatally damage it, it would ring like a bell, like getting shot be a gun. You would hear it, and sound waves can be (and are) picked up by strain gauges. It may not be precise, but knowing that it happened would be useful info.ISTR astronauts saying they could hear MMOD strikes on the ISS. That suggests non-fatal hits can be picked up by microphones. Spread a few along the main structures and triangulate to find the source, that should take far less than 500 lbs.
Then what?
Quote from: SWGlassPit on 08/29/2016 06:32 pmThen what?Look for it.
What's next after that?
Quote from: guckyfan on 08/29/2016 06:42 pmQuote from: SWGlassPit on 08/29/2016 06:32 pmThen what?Look for it.What's next after that?
So in other words, compound conservatism. Sounds like a good recipe to increase overall costs.
It's not the same system. It wasn't designed to be used to detect MMOD strikes, and -- surprise -- it didn't do a good job of doing so. No human spacecraft has flown with an MMOD strike detection system.
If that even works (signal-to-noise ratio issues abound here), what would that accomplish? You look at it and go, "yep, that's a strike." Then what?
Quote from: SWGlassPit on 08/29/2016 06:32 pmIf that even works (signal-to-noise ratio issues abound here), what would that accomplish? You look at it and go, "yep, that's a strike." Then what?If pieced into the main room duck tape a patch across the hole to stop the air escaping. Pipes can be sealed with a plaster. Broken windows can be covered.Damage to outside parts of the spacecraft may have to be repaired by a robot or EVA. Such a repair was performed to the ISS solar panels on January 30, 2007. There may be a way to glue or weld heat shield material across a hole the size of Columbia's.