This is interesting.
APAS is a pretty obsolete system, but it would be nice to have a docking standard for everyone, for safety and rescue reasons, and flexibility. I’m sure that Frank Wolf would have a hissy fit, though, if we were to share the NDS with the Chinese. The question is, would the station share an orbit with the ISS, or be in a different one? One of my dreams is seeing an actual community and infrastructure develop in one place, which again, would promote safety, and eliminate the idiotic (in my opinion, as I describe in my book) requirement for a “lifeboat” to evacuate everyone in the ISS all the way back to earth.
I think your dream is inescapable at this point and will inspire more dreams as well.
I’d be in favour of a lifeboat that could take the entire crew to the moon! It would have to be fueled in orbit, which would be great for increasing the size of the launch services market.
I agree on the need for a universal docking standard, akin to a PCI or USB standard. Having one would greatly enable a multiplicity of solutions that can plug-n-play with one another – spacecraft, Bigelow modules, universal docking nodes, propulsion modules, and so forth. One can only hope…
Then you get RobotGuy’s Legos which I still consider prophetic.
Ken Murphy wrote:
Your comparison is apt but for reasons you likely didn’t intend.
PCI and USB co-exist quite nicely on PCs because they fulfill the very different requirements for permanent and temporary connection of peripherals. You wouldn’t want a removable drive to use PCI because it would be a hassle to install/remove. Likewise, you wouldn’t want a video card to use USB because the performance would suck.
CBM and NDS are analogous to PCI and USB for space stations. As I noted elsewhere, it’s a historical accident that CBM wound up being used for free-flying cargo spacecraft. Apart from that anomaly, CBM is consistently used for permanent connections, and docking mechanisms like NDS are used for temporary connections.
I can’t tell from the article–is IBDM different from CBM? What’s NDS? Why so many systems (in particular, why, I wonder, did the Chinese not adopt APAS directly, and is their system incompatible with the original version? At first glance, this seems foolhardy. You think it’s bad carrying a lot of keys around on your key chain, but imagine what it’s like if your space ship has four separate ports. Oh brother.
NDS is the new NASA Docking System (which looks like it’s going to be Boeing’s iLIDS). The problem with CBM is that it requires berthing, and someone on both sides of it, with power. I.e., it doesn’t meet the requirements for an emergency evacuation.
Thus the universal docking adapter with six ports of three different types. h/t to RobotGuy.
Ok, I read up a little more, and I understand what IBDM and NDS are, although I fail to understand what the point of them is. Ignore my previous comment: why not, other than politics, adopt CBM as a universal system? To me, the large opening makes a lot more sense than the little things APAS and other derived/similar systems use, including NDS and IBDM?
We’re going to be stuck with both CBM and NDS for a long time. The latter is much more flexible, (e.g., allowing docking to an unmanned facility), but the former will stick around for its ability to transfer large objects.
Thanks for the answers, btw. This raises a couple more questions but I’ll ask in the new thread.
Note that Dragon can’t serve as a lifeboat currently, because it has to have someone in the station, with power, to unberth from the CBM, even though it’s functionally capable of doing so with a rudimentary life support system. One of the key changes for commercial crew will be adoption of the NDS. One more reason that we should be accelerating that capability, because a Dragon lifeboat would allow the addition of another crew member, doubling or maybe even quadrupling the science that could be performed at the station.
Agreed. The berthing process is too cumbersome. Perhaps something Bigelow could test on one of his space station tests? He shouldn’t have the problems the Chinese have licensing US tech. Although one would hope that the US Government would be gracious enough to make something like a civilian docking system public knowledge and an open standard.