LSAM and an unmanned CEV in lunar orbit?

wrote:

Then how about sending a guy over with a wire and pull the vehicle in ?
Much as Arthur C Clarke wrote way back when ?

The vehicle does rendez-vous to 100 meter distance, and the astronaut
maneuvres it in.


Although they never did it, the Soviets had a plan to dock two Voskhods
together by having one extend a loop of wire that the second one would
clamp onto via a hook. Then the wire would be reeled in until the two
spacecraft came into contact.

Pat

"Pat Flannery" wrote in message
...


wrote:

Then how about sending a guy over with a wire and pull the vehicle in ?
Much as Arthur C Clarke wrote way back when ?

The vehicle does rendez-vous to 100 meter distance, and the astronaut
maneuvres it in.


Although they never did it, the Soviets had a plan to dock two Voskhods
together by having one extend a loop of wire that the second one would
clamp onto via a hook. Then the wire would be reeled in until the two
spacecraft came into contact.

Given the experience that early astronauts and cosmonauts had with tethered
EVA's, specifically trying to pull on the tether to maneuver in space, I
think such an approach would be disastrous.

Besides, as Henry points out, it's proven to be fairly easy to use robotic
arms to capture and berth large modules (like Hubble was done for servicing
missions). The way that the shuttle arm's end effector grapples a grapple
fixture allows for a bit of "slop" in the operation. Once you've got a good
solid grapple, the arm's movements with the grappled module can be very
precise for the berthing operation.

Jeff
--
Remove icky phrase from email address to get a valid address.

Jeff Findley wrote:

Given the experience that early astronauts and cosmonauts had with tethered
EVA's, specifically trying to pull on the tether to maneuver in space, I
think such an approach would be disastrous.



You can picture the two spacecraft slamming together pretty violently;
maybe the plan was to get the two rotating on opposite ends of the
wire, and then reel them together against the centrifugal force; they
had some plan to do that with a couple of their spacecraft also (the
spinning part) but I can't remember if it was supposed to be with
Voskhods our Soyuz.
The strangest idea was....are you ready for this? A EVA from a Voskhod
prior to Leonov's ...by a dog!

Besides, as Henry points out, it's proven to be fairly easy to use robotic
arms to capture and berth large modules (like Hubble was done for servicing
missions). The way that the shuttle arm's end effector grapples a grapple
fixture allows for a bit of "slop" in the operation. Once you've got a good
solid grapple, the arm's movements with the grappled module can be very
precise for the berthing operation.



I still think it's a lot easier just to dock them, ala the Mir modules
(which then got moved to their appropriate ports via a automatic robotic
arm fixture that plugged into a receptacle on the Mir docking module.)
Our conception of using the mechanical arms limits one to manned
operations; given the bone loss problem in zero G, that ability to
assemble the whole Mars ship automatically over a period of months, then
put the crew on board when it's pretty much finished would seem to be a
advantage in this regard.
NASA seems (or at least seemed- I don't know how Constellation is going
to work.) dead set that people are going to be doing all of this
manually, as anything else is a threat to manned spaceflight- and I
think that is limiting our space abilities by shoehorning us into doing
things manually that could be done by uncrewed vehicles.

Pat

In article ,
Pat Flannery wrote:
Besides, as Henry points out, it's proven to be fairly easy to use robotic
arms to capture and berth large modules (like Hubble was done for servicing
missions)...

I still think it's a lot easier just to dock them...

No, actually it's harder. It makes the approach trickier, because you
*intend* to slam into the target spacecraft and have to get the location
just right, and it calls for more structural strength in both. Berthing
is slower, gentler, and better controlled, at the cost of needing a bit
more infrastructure.

Our conception of using the mechanical arms limits one to manned
operations...

Not necessarily. There is no fundamental technical difficulty in running
even the current station arm from the ground. (JSC does not like the
idea, and last I heard -- that was a while back -- hadn't okayed it, but
the hardware can do it.) Because berthing is a slow, controlled process,
you can deal with modest communications lags just by taking your time.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |