-
#140 by HappyMartian on 29 Sep, 2013 16:31
-
Here is an image of an astronaut carrying a battery ORU at HST. Although the astronaut's feet are attached to the arm, there is no reason why the same operation could not be performed with the astronaut's feet attached to handrails.
There are many reasons that are intuitively obvious.
How does the battery get from the storage location to the astronaut who is fixed on the handrails. The battery is too heavy to be "dragged" to be walked into place. How is the foot restraint on the hand rails placed there? What says a foot restraint on the handrail can be placed in the right position? What says the handrail can take the loads? Where is the foot restrain carried?
The issue on the table is whether an astronaut can translate from Orion to the battery bay on HST while carrying a battery ORU.
As mention before, the battery ORU is something like 36 inches x 32 inches x 11 inches, and weighs some 400 pounds.
While I am at it, I should ask if anyone questions whether astronauts can change out the rate sensor units (gyros) using Orion.
1. Battery energy storage efficiency is changing. Could the replacement batteries be lighter or smaller than the current batteries?
2. Could each battery pack be broken into four, or even eight, smaller units that could be 'snapped together' just prior to their installation?
If using a Delta IV Heavy is doable for an Orion mission to service the Hubble, that would be nifty. Having the Delta IV Heavy tested in LEO as a secondary or backup launcher for various Orion missions could be quite useful.
However, the SLS also needs to be tested with the Orion and crew in LEO. The SLS could offer some useful extra launch and delta-v capability along with some mission risk reducing options, such as an inflatable servicing/airlock/docking/mission module with an arm or possibly even two arms.
3. Would it be reasonable to use the ESA Service Module to reboost the Hubble only after the ESA Service Module has done the deorbit burn for the Orion and then independently made a rendezvous and docking with the Hubble?
4. In that mission scenario, would it be reasonable to keep the ESA Service Module docked long-term to the Hubble for possible backup electrical power, 3 axis control, and future reboost or deorbit options?
-
#141 by Jim on 29 Sep, 2013 19:08
-
No, an astronaut can not translate with a 400lb object. No corroborating data is needed, it is intuitively obvious.
-
#142 by Danderman on 29 Sep, 2013 21:27
-
1. Battery energy storage efficiency is changing. Could the replacement batteries be lighter or smaller than thecurrent batteries?
2. Could each battery pack be broken into four, or even eight, smaller units that could be 'snapped together' just prior to their installation?
There some possibility that the three battery ORU could be assembled on-orbit, allowing astronauts to carry one third of a battery ORU at a time. This is still over 100 lbs per load, however.
IF there were a hard requirement to replace the Hubble batteries, and the only option were to service using Orion, then alternatives such as reducing the mass of the batteries or developing some sort of translation tool would be considered.
-
#143 by veblen on 29 Sep, 2013 21:33
-
yeah lets not discuss risk or how freakin expensive this is going to be or what we get out of it in terms of science, or some practical alternatives, let's just focus on what you think you know about robotic arms
I am happy to talk about the risks of using Orion for Hubble Servicing.
I am happy talk about HST servicing requirements that require an arm.
I am not happy to talk about how it is stupid to service HST. That requires its own thread.
"Stupid" your word not mine. And I followed the last repair mission to HST very closely. The planning and effort involved rivalled an Apollo mission. Hubble is child of Shuttle. Shuttle has gone away. Better to manage Hubble conservatively into very old age from the ground, as its excellent minders are currently doing.
-
#144 by deltaV on 17 Oct, 2013 21:01
-
It's obvious that one cannot walk around carrying a 400 lb object here on Earth but why can't that be done in space? If you limit acceleration to say 0.25 m/s/s you only have to push with 10 lbf. Keep speeds low to avoid accidents. Note that people pushing heavy boats around is an analogous situation here on Earth.
-
#145 by Jim on 17 Oct, 2013 21:13
-
It's obvious that one cannot walk around carrying a 400 lb object here on Earth but why can't that be done in space? If you limit acceleration to say 0.25 m/s/s you only have to push with 10 lbf. Keep speeds low to avoid accidents. Note that people pushing heavy boats around is an analogous situation here on Earth.
Because there is no way to control the mass and translate at the same time while EVA. And it would be an analogous situation on Earth wrt heavy boats only if the person pushing was in separate boat and using only one hand.
As for limiting acceleration to 0.25 m/s/s, how would you ensure that? Are you going to put a inertial reference system on the battery to measure the acceleration or are you going to calibrate the astronauts arms to ensure that they don't push too hard? -
#146 by HappyMartian on 17 Oct, 2013 23:49
-
1. Battery energy storage efficiency is changing. Could the replacement batteries be lighter or smaller than thecurrent batteries?
2. Could each battery pack be broken into four, or even eight, smaller units that could be 'snapped together' just prior to their installation?
There some possibility that the three battery ORU could be assembled on-orbit, allowing astronauts to carry one third of a battery ORU at a time. This is still over 100 lbs per load, however.
IF there were a hard requirement to replace the Hubble batteries, and the only option were to service using Orion, then alternatives such as reducing the mass of the batteries or developing some sort of translation tool would be considered.
If an arm or two is needed, then:
"Similarly, the notional Robotics and EVA Module (REM) is envisioned as an 'add on’ airlock to other destination elements, consisting of a suitlock with two suitports, at least one robotic arm with a grapple fixture and EVA positioning end effectors, an international docking system standard interface, an external equipment pallet, a crew lock, and mounting points to which elements and payload hardware can be mounted.'"
From: Space agencies push for deep space cooperation By Marshall Murphy October 14, 2013
At: http://www.nasaspaceflight.com/2013/10/space-agencies-deep-space-cooperation/
Are there any real show stoppers if NASA is given the task to use Orion for Hubble Service Missions? -
#147 by veblen on 18 Oct, 2013 00:10
-
not "showstoppers", just no need to repair Hubble
Magellan...
http://www.gmto.org/overview.html
and there are other observatories planned both on earth and launched to space
-
#148 by HappyMartian on 18 Oct, 2013 15:20
-
not "showstoppers", just no need to repair Hubble
Magellan...
http://www.gmto.org/overview.html
and there are other observatories planned both on earth and launched to space
Both Earth and space based telescopes have their particular strengths.
Note:
"The usefulness of adaptive optics versus HST observations depends strongly on the particular details of the research questions being asked. In the visible bands, adaptive optics can only correct a relatively small field of view, whereas HST can conduct high-resolution optical imaging over a wide field. Only a small fraction of astronomical objects are accessible to high-resolution ground-based imaging; in contrast Hubble can perform high-resolution observations of any part of the night sky, and on objects that are extremely faint."
From: Hubble Space Telescope Wikipedia
At: http://en.wikipedia.org/wiki/Hubble_Space_Telescope
Astronomical need for space telescope observational time will not be fully met by new space based telescopes.
Space based telescopes also face a more hazardous environment, restricted repair and servicing options, and a quite limited lifespan when compared to Earth based telescopes, thus significant backup space telescope capabilities are needed for both astronomical research and essential NEO defense purposes.
The ability of astronauts to use Orion and its capabilities to do orbital change, repair, and servicing missions for space telescopes, space modules, and satellites needs to be experimentally tested and confirmed in LEO before trying to do such missions in beyond LEO space.
Our need for extensive experience in using the robust capabilities of Orion to repair or service space assets is unlikely to be satiated for many decades.
Using Orion for ongoing Hubble Servicing Missions makes sense if we really are serious about the development of cislunar space and devising a layered defense capability against NEOs. -
#149 by Danderman on 24 Dec, 2013 14:45
-
The premise of this thread is to determine the suitability of Orion for servicing Hubble for a "batteries and gyros" changeout mission.
If you are interested in using Orion to change out actual HST instruments, this is not the thread for you.
If you want to talk about whether Hubble should be serviced commercially, there is a thread for that.
Where we left off, Jim made the point that the Hubble batteries are too massive for an astronaut to translate them from some point in the Orion payload bay (or inside Orion itself), although the batteries are compact, without the use of some sort of RMS.
I am attaching an image of an astronaut translating an ISS Pump module - although the RMS is moving the astronaut, the astronaut is manipulating the pump module. Later images show the astronaut moving the Pump module into position. I have the impression that if the Hubble batteries were close enough to Hubble that the arm itself would not be required, the astronauts could do the translation themselves.
-
#150 by Jim on 24 Dec, 2013 15:28
-
I am attaching an image of an astronaut translating an ISS Pump module - although the RMS is moving the astronaut, the astronaut is manipulating the pump module. Later images show the astronaut moving the Pump module into position. I have the impression that if the Hubble batteries were close enough to Hubble that the arm itself would not be required, the astronauts could do the translation themselves.
Wrong impression and quite nonsensical. The astronaut is not translating, he is only a fixture to hold the pump. He is holding on with two hands and both feet are in a foot restraint. That is how he can handle it because he firmly anchored. He would not be able do anything with his feet free. How do you propose he translate without the arm? Walk out of the restraints?
This is basic EVA engineering: It takes two hands to translate and it takes two hands to manipulate a large, heavy object.
How do you propose they do either?
Anytime an astronaut has handled a large object, he has been restrained. EVA astronauts do not translate by hand with large objects. Basic EVA engineering -
#151 by HappyMartian on 25 Dec, 2013 12:16
-
I am attaching an image of an astronaut translating an ISS Pump module - although the RMS is moving the astronaut, the astronaut is manipulating the pump module. Later images show the astronaut moving the Pump module into position. I have the impression that if the Hubble batteries were close enough to Hubble that the arm itself would not be required, the astronauts could do the translation themselves.
Wrong impression and quite nonsensical. The astronaut is not translating, he is only a fixture to hold the pump. He is holding on with two hands and both feet are in a foot restraint. That is how he can handle it because he firmly anchored. He would not be able do anything with his feet free. How do you propose he translate without the arm? Walk out of the restraints?
This is basic EVA engineering: It takes two hands to translate and it takes two hands to manipulate a large, heavy object.
How do you propose they do either?
Anytime an astronaut has handled a large object, he has been restrained. EVA astronauts do not translate by hand with large objects. Basic EVA engineering
Jim, are you saying such a mission is fundamentally impossible or just that it is not doable in the manner suggested?
If the President and Congress wanted the Orion for Hubble Service Mission to be done, how could it be accomplished while minimizing risks? -
#152 by Jim on 25 Dec, 2013 22:55
-
Jim, are you saying such a mission is fundamentally impossible or just that it is not doable in the manner suggested?
If the President and Congress wanted the Orion for Hubble Service Mission to be done, how could it be accomplished while minimizing risks?
An arm of some kind will be required. -
#153 by Danderman on 25 Dec, 2013 23:10
-
Jim, are you saying such a mission is fundamentally impossible or just that it is not doable in the manner suggested?
If the President and Congress wanted the Orion for Hubble Service Mission to be done, how could it be accomplished while minimizing risks?
An arm of some kind will be required.
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
-
#154 by Jim on 25 Dec, 2013 23:30
-
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
A robotic mission negates the need for the arm or EVA. -
#155 by Danderman on 25 Dec, 2013 23:43
-
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
A robotic mission negates the need for the arm or EVA.
Now that you have described the robotic mission as some sort of augmentation of HST rather than a robotic servicer, it makes a lot more sense.
I just don't know if the HST instruments would work with a multi-ton object attached to the base. I recall that the "flutter" from solar panels would interfere with observations, so it is TBD whether the loads from a new spacecraft mated to the docking adapter would similarly interfere with observations.
-
#156 by HappyMartian on 26 Dec, 2013 12:18
-
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
A robotic mission negates the need for the arm or EVA.
Any robot and spacecraft relatively 'off the shelf' that could be modified for such a servicing mission?
Or would you want the robot to permanently dock to the Hubble and assume some of the Hubble's capabilities?
What exactly could the robot do in a servicing mission?
Approximately how much $ and time to prepare and launch the robot? -
#157 by Danderman on 26 Dec, 2013 19:07
-
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
A robotic mission negates the need for the arm or EVA.
Any robot and spacecraft relatively 'off the shelf' that could be modified for such a servicing mission?
Or would you want the robot to permanently dock to the Hubble and assume some of the Hubble's capabilities?
What exactly could the robot do in a servicing mission?
Approximately how much $ and time to prepare and launch the robot?
Jim's approach is not a "Servicing mission" but rather a permanent addition to HST to provide power and attitude control, much like a system that SkyCorp was proposing for GEO comsats.
The robot would not replace or augment any HST science capabilities.
Therefore, the robot would be a direct competitor to a "gyros and batteries" only servicing mission conducted by humans.
-
#158 by HappyMartian on 27 Dec, 2013 13:07
-
An arm or some sort of rig that would be able to help transport relatively compact batteries from a bay in the service module to the appropriate HST bay. It doesn't seem like rocket science.
A robotic mission negates the need for the arm or EVA.
Any robot and spacecraft relatively 'off the shelf' that could be modified for such a servicing mission?
Or would you want the robot to permanently dock to the Hubble and assume some of the Hubble's capabilities?
What exactly could the robot do in a servicing mission?
Approximately how much $ and time to prepare and launch the robot?
Jim's approach is not a "Servicing mission" but rather a permanent addition to HST to provide power and attitude control, much like a system that SkyCorp was proposing for GEO comsats.
The robot would not replace or augment any HST science capabilities.
Therefore, the robot would be a direct competitor to a "gyros and batteries" only servicing mission conducted by humans.
Orion can do a significant and relatively quick boost of the 24,500 lb (11,110 kg) Hubble to a higher orbit.
If the robot uses electric rocket propulsion to boost Hubble to a higher orbit, that might mean a period of a month or more when the Hubble might not be available for doing astronomical observations.
If the robot remained attached to Hubble would there be problems with a new center of gravity and any still functional "gyros" and also issues with the additional solar panels or could the robot have a distributed mass in its arms such that the Hubble is slid into the robot's long and heavy arms and thus the center of mass wouldn't change?
Could it be useful to have a dual mission with both the robot that remains attached to Hubble and Orion launched on the same SLS?
Could such a mission be seen as training for future missions to service space telescopes and important satellites?
Could the Orion's ESA Service Module have room for an attached folding or telescoping composite arm, or even arms, to hold or restrain the astronaut?
Edited. -
#159 by Jim on 27 Dec, 2013 13:26
-
Could it be useful to have a dual mission with both the robot that remains attached to Hubble and Orion launched on the same SLS?
Could such a mission be seen as training for future missions to service space telescopes and important satellites?
Don't need SLS or Orion for this. Any one of the existing ELV's can do it
No "training" is needed. Already have done HST repair missions and there is the ISS.
And there are no "important" satellites that would need to be repaired