Quote from: Lars_J on 08/22/2011 04:09 amThe great irony in all of this is of course that in the vehicle that NASA has the most docking experience in - Shuttle - the person who pilots the docking is *not* looking out the window - he/she is looking at computer monitors, where the center-line video feed also is displayed. (unless I am mistaken)Dockings just aren't performed with the unaided Mark 0 eyeball.You're not mistaken, but you are missing the point that if the camera fails, the pilot can fly a backout using the window view.
The great irony in all of this is of course that in the vehicle that NASA has the most docking experience in - Shuttle - the person who pilots the docking is *not* looking out the window - he/she is looking at computer monitors, where the center-line video feed also is displayed. (unless I am mistaken)Dockings just aren't performed with the unaided Mark 0 eyeball.
You're not mistaken, but you are missing the point that if the camera fails, the pilot can fly a backout using the window view.
That's why you install redundant cameras on independent circuits.
Quote from: Jorge on 08/22/2011 04:24 amQuote from: Lars_J on 08/22/2011 04:09 amThe great irony in all of this is of course that in the vehicle that NASA has the most docking experience in - Shuttle - the person who pilots the docking is *not* looking out the window - he/she is looking at computer monitors, where the center-line video feed also is displayed. (unless I am mistaken)Dockings just aren't performed with the unaided Mark 0 eyeball.You're not mistaken, but you are missing the point that if the camera fails, the pilot can fly a backout using the window view.What does Shuttle do if the fly-by-wire system fails? Trick question, it doesn't. Shuttle has redundancies built into the fly-by-wire system so that never happens.I wonder if NASA could be flexible enough to allow a similar level of redundancy in the camera system so that a window isn't an absolute requirement but can be replaced with a system of comparable reliability (somehow).In your understanding, Jorge, would a periscope satisfy the CCP window requirement?
Quote from: docmordrid on 08/22/2011 04:30 amThat's why you install redundant cameras on independent circuits. How are you going to fit multiple cameras in front of the hatch window?
Why would you put them at hatch window?Put them at the top where it angles from the side walls to the adapter, with the view in line with the docking interface.
Quote from: docmordrid on 08/22/2011 04:37 amWhy would you put them at hatch window?Put them at the top where it angles from the side walls to the adapter, with the view in line with the docking interface.To line up with the bulls-eye on the PMA hatch:
How are you going to fit multiple cameras in front of the hatch window?
Quote from: Ronsmytheiii on 08/22/2011 04:33 amHow are you going to fit multiple cameras in front of the hatch window?Use beam splitting optics.
QuoteQuote from: apace on 08/21/2011 11:58 pmAt the end, Boeing, SNC and SpaceX can go to NASA and tell them, change your rules or you will have no crewed vehicles from us...Something of a prisoner's dilemma there. Only takes one to say "yes" and if the requirement stands as-is, CST-100 (or Orion) would appear to have the advantage.Especially when one, and possibly two, of them have a technical solution in-hand.
Quote from: apace on 08/21/2011 11:58 pmAt the end, Boeing, SNC and SpaceX can go to NASA and tell them, change your rules or you will have no crewed vehicles from us...Something of a prisoner's dilemma there. Only takes one to say "yes" and if the requirement stands as-is, CST-100 (or Orion) would appear to have the advantage.
At the end, Boeing, SNC and SpaceX can go to NASA and tell them, change your rules or you will have no crewed vehicles from us...
Quote from: cosmicvoid on 08/22/2011 05:37 amQuote from: Ronsmytheiii on 08/22/2011 04:33 amHow are you going to fit multiple cameras in front of the hatch window?Use beam splitting optics.Very simple but clever answer. And so obvious once it is brought up!
Quote from: Robotbeat on 08/22/2011 06:05 amQuote from: cosmicvoid on 08/22/2011 05:37 amQuote from: Ronsmytheiii on 08/22/2011 04:33 amHow are you going to fit multiple cameras in front of the hatch window?Use beam splitting optics.Very simple but clever answer. And so obvious once it is brought up!IIRC someone named Richard Speck on this forum discussed his <1g space qualified camera. You can fit a dozen around the edge of that window and still look out the center, or mount them outside as suggested.I learned from NSF that the Saturn V used fiber optics to bring images of its F1 engines to cameras. These aren't even new clever ideas.But these are not "Mark 0 eyeballs" on the target.
The "problem" is easy to resolve.You use a hand-held controller and float over to the window that is in the forward facing hatch. Soyuz already has a small hand-held controller. (I couldn't find an on-line photo, but essentially we're talking about a wired device the size of a paperback book.)
Happy digging. Let us know what you find.
Quote from: Ronsmytheiii on 08/22/2011 03:46 amQuote from: Robotbeat on 08/22/2011 03:29 amIn my opinion, there must be push-back from the people actually directly designing and building (etc) the vehicle, or it won't be cost-effective. If the negotiating position is too strong for one of the parties, a considerably-non-optimal solution results.Have you ever heard the rule of commerce, that the customer is always right? Indeed NASA has every right to request a requirement that they deem necessary, as they have had a decade of ISS experience plus more with Mir. If you deem that overly conservative, think of how expensive ISS is and how much of a stake NASA has in the program. So if a couple of vehicles cannot meet the requirement, then NASA has every right to exclude them to protect its investment. However, it will be interesting to see whether or not a periscope could be defined as a "window" since it is basically light reflected from a window. Seems like an easy solution. Have you ever worked with over-demanding customers with stupid requirements which come only from their preferred solution and are not really needed for their given application? I have. Multiple times.They usually end up with something that is multiple times more expensive but no more superior than the alternatives (and often times inferior in areas which really matter). I know, I know, it's anecdote, but that's reality. The customer has every legal right to shoot themselves in the foot if they want to.EDIT:For clarification: I'm still seeking confirmation or denial about whether or not this window thing is an actually important requirement. My statement above is in the case that it is a burdensome but unnecessary requirement.
Quote from: Robotbeat on 08/22/2011 03:29 amIn my opinion, there must be push-back from the people actually directly designing and building (etc) the vehicle, or it won't be cost-effective. If the negotiating position is too strong for one of the parties, a considerably-non-optimal solution results.Have you ever heard the rule of commerce, that the customer is always right? Indeed NASA has every right to request a requirement that they deem necessary, as they have had a decade of ISS experience plus more with Mir. If you deem that overly conservative, think of how expensive ISS is and how much of a stake NASA has in the program. So if a couple of vehicles cannot meet the requirement, then NASA has every right to exclude them to protect its investment. However, it will be interesting to see whether or not a periscope could be defined as a "window" since it is basically light reflected from a window. Seems like an easy solution.
In my opinion, there must be push-back from the people actually directly designing and building (etc) the vehicle, or it won't be cost-effective. If the negotiating position is too strong for one of the parties, a considerably-non-optimal solution results.
BTW, was this the same draft document that Wayne Hale described as "mind-numbing" in his blog? Because I'm starting to feel a little numb.
This will be a big problem.On an engineering effort for a system that would have ridden in Orion, part of the requirements was JSC-62550, Strength Design and Verification Criteria for Glass, Ceramics and Windows in Human Space Flight Applications (I just found this through a Google Search.) It goes on and on, including paragraphs telling you how to apply the document when the document does not apply. This is based on their extensive track record of having designed a successful manned spaceflight vehicle in the 1970's.
Quote from: Robotbeat on 08/22/2011 04:00 amHave you ever worked with over-demanding customers with stupid requirements which come only from their preferred solution and are not really needed for their given application? I have. Multiple times.They usually end up with something that is multiple times more expensive but no more superior than the alternatives (and often times inferior in areas which really matter). I know, I know, it's anecdote, but that's reality. The customer has every legal right to shoot themselves in the foot if they want toHow many of these companies have experience with docking? Answer is none with the exception of Boeing, who is including windows. The logic of the window seems to be the use of a HHL like shuttle, which requires a two man crew (ie HHL operator and the person manning the stick) and would imagine the hatch window will be used as the centerline camera. Both are just like shuttle operation, and therefore the requirements are just like shuttle.Soyuz uses the autonomous Kurs system, as well as the manual mode through the periscope and forward docking camera as well as laser range finder. Seems just like the commercial requirements. Commercial also had input, but dont dismiss the experience of NASA as "frivolous"
Have you ever worked with over-demanding customers with stupid requirements which come only from their preferred solution and are not really needed for their given application? I have. Multiple times.They usually end up with something that is multiple times more expensive but no more superior than the alternatives (and often times inferior in areas which really matter). I know, I know, it's anecdote, but that's reality. The customer has every legal right to shoot themselves in the foot if they want to
Quote from: Ronsmytheiii on 08/22/2011 04:19 amQuote from: Robotbeat on 08/22/2011 04:00 amHave you ever worked with over-demanding customers with stupid requirements which come only from their preferred solution and are not really needed for their given application? I have. Multiple times.They usually end up with something that is multiple times more expensive but no more superior than the alternatives (and often times inferior in areas which really matter). I know, I know, it's anecdote, but that's reality. The customer has every legal right to shoot themselves in the foot if they want toHow many of these companies have experience with docking? Answer is none with the exception of Boeing, who is including windows. The logic of the window seems to be the use of a HHL like shuttle, which requires a two man crew (ie HHL operator and the person manning the stick) and would imagine the hatch window will be used as the centerline camera. Both are just like shuttle operation, and therefore the requirements are just like shuttle.Soyuz uses the autonomous Kurs system, as well as the manual mode through the periscope and forward docking camera as well as laser range finder. Seems just like the commercial requirements. Commercial also had input, but dont dismiss the experience of NASA as "frivolous" Actually, several thoughts here. First, these are only draft requirements and NASA is listening to input from the commercial companies. If no one complains or takes issue with the window requirement nothing will definitely change. Second, many if not all the companies are planning automated rendezvous. If you want manual, you can do it just as fine with cameras or other devices. So it is a valid debate on teh use of a window. This is clearly an emotional item from pilots even though these vehicles will be far more like a video game then a jet. Third, let's face it - there will be no company that will satisfy ever single requirement. Some wil have to be waived by NASA. Some the company will say "ok, this is what the model comes with, if you want tail fins, that costs extra - are you happy to pay X million more?" As far as I can tell this requirement is not a big deal for the companies, but we will see. Hopefully that is true because it does drive costs/design.