David J. Shayler - The Hubble Space Telescope: From Concept to Success
Here you can read online David J. Shayler - The Hubble Space Telescope: From Concept to Success full text of the book (entire story) in english for free. Download pdf and epub, get meaning, cover and reviews about this ebook. year: 2016, publisher: Springer, genre: Science fiction. Description of the work, (preface) as well as reviews are available. Best literature library LitArk.com created for fans of good reading and offers a wide selection of genres:
Romance novel
Science fiction
Adventure
Detective
Science
History
Home and family
Prose
Art
Politics
Computer
Non-fiction
Religion
Business
Children
Humor
Choose a favorite category and find really read worthwhile books. Enjoy immersion in the world of imagination, feel the emotions of the characters or learn something new for yourself, make an fascinating discovery.
- Book:The Hubble Space Telescope: From Concept to Success
- Author:
- Publisher:Springer
- Genre:
- Year:2016
- Rating:3 / 5
- Favourites:Add to favourites
- Your mark:
The Hubble Space Telescope: From Concept to Success: summary, description and annotation
We offer to read an annotation, description, summary or preface (depends on what the author of the book "The Hubble Space Telescope: From Concept to Success" wrote himself). If you haven't found the necessary information about the book — write in the comments, we will try to find it.
The highly successful Hubble Space Telescope was meant to change our view and understanding of the universe. Within weeks of its launch in 1990, however, the space community was shocked to find out that the primary mirror of the telescope was flawed. It was only the skills of scientists and engineers on the ground and the daring talents of astronauts sent to service the telescope in December 1993 that saved the mission.For over two decades NASA had developed the capabilities to service a payload in orbit. This involved numerous studies and the creation of a ground-based infrastructure to support the challenging missions. Unique tools and EVA hardware supported the skills developed in crew training that then enabled astronauts to complete a demanding series of spacewalks.Drawing upon first hand interviews with those closely involved in the project over thirty years ago this story explains the development of the servicing mission concept and the hurdles that had to be overcome to not only launch the telescope but also to mount the first servicing mission a mission that restored the telescope to full working order three years after its launch, saved the reputation of NASA, and truly opened a new age in understanding of our place in space.This is not just a tale of space age technology, astronauts and astronomy. It is also a story of an audacious scientific vision, and the human ingenuity and determination to overcome all obstacles to make it possible. Hubble Space Telescope: From Concept to Success is a story of an international partnership, dedicated teamwork and a perfect blend of human and robotic space operations that will inspire people of all ages. The subsequent servicing missions that enabled the telescope to continue its scientific program beyond its 25th year in orbit are described in a companion volume Enhancing Hubbles Vision: Servicing a National Treasure.
David J. Shayler: author's other books
Who wrote The Hubble Space Telescope: From Concept to Success? Find out the surname, the name of the author of the book and a list of all author's works by series.
David J. Shayler
David J. Shayler
Christy Peterson
Kevin Hartnett
N Okamoto
Michael Soluri
Michael D. Cole
David Shayler
The Hubble Space Telescope: From Concept to Success — read online for free the complete book (whole text) full work
Below is the text of the book, divided by pages. System saving the place of the last page read, allows you to conveniently read the book "The Hubble Space Telescope: From Concept to Success" online for free, without having to search again every time where you left off. Put a bookmark, and you can go to the page where you finished reading at any time.
Light
Font size:
↓
↑
Reset
Interval:
↓
↑
Bookmark:
Make
Springer Science+Business Media New York 2016
David J. Shayler and David M. Harland The Hubble Space Telescope Springer Praxis Books 10.1007/978-1-4939-2827-9_11. Deployment
David J. Shayler 1 and David M. Harland 2
(1)
Astro Info Service Ltd., Halesowen, West Midlands, UK
(2)
Kelvinbridge, Glasgow, UK
I really did not want to mess this up.
Steve Hawley, RMS operator, STS-31
On April 25, 1990 professional astronomer, NASA astronaut and STS-31 Mission Specialist Steven A. Hawley, was looking intently out of the aft flight deck windows of the space shuttle Discovery orbiting 380 miles (600 km) above the Earth, at the large payload on the end of the robotic arm that he was controlling. To his left was Mission Commander Loren J. Shriver, flying the orbiter. With them on this the 35th mission of the shuttle series were Mission Specialists Bruce McCandless II and Kathryn D. Sullivan, both of whom were on the middeck, preparing for a possible spacewalk if things went wrong with the payload. Floating between decks was Pilot Charles F. Bolden Jr., who was helping both pairs of colleagues. It was a tense time.
For Hawley, it seemed all attention was on his actions over the next few minutes. He was also monitoring the small TV screens which displayed views of the payload that he was about to deploy: the Hubble Space Telescope. It seemed appropriate that the responsibility to place the long-awaited Great Observatory into orbit should fall to a professional astronomer. For many who had worked on the project, Hubble had dominated their entire professional career, and it carried the hopes and expectations of the astronomical community, together with scores of designers, engineers, contractors, scientists, controllers, managers, politicians and even the general public at large.
Deploying a Telescope
The responsibility of his next actions was not lost on Hawley. I remember, throughout the mission, but in particular on deploy day, thinking about all of the people and all the years of effort that had led up to this moment. To some extent, what I was doing was just representing the community of scientists and engineers who had taken [Lyman] Spitzers idea for an optical telescope on-orbit and made it a reality. So I really did not want to mess this up. I did feel, particularly as a professional astronomer, the weight of the astronomical community. They had done all their jobs, and its up to me to finish it off. I remember thinking about that quite a lot. 
Looking out the overhead aft flight deck windows [left to right] Bruce McCandless, Steve Hawley and Loren Shriver.
Unwanted motions and collision avoidance
Hawley, an astronaut for 12 years, was on his third flight into space, fully proficient and experienced in operating the Remote Manipulator System (RMS). Although he had operated the arm in simulators and had gained insights from colleagues who had already operated it in space, he had yet to fly the arm in space. But the task was daunting. Hubble was by far the largest mass that the arm had been required to hoist out of the payload bay to date, and the tolerances were tight, so the trick was to recognize the momentum of movement and be able to react quickly enough to do something about it.
Hawley explained this as the worse failure you can have, when you are trying to unberth Hubble and it is very near the orbiter structure [where] tolerances are very small. With a run-away motor you can have your first hypothetical failure. As there was no collision avoidance software available, the collision avoidance is the RMS operator and you can make [all kinds] of estimates as to how long it would take the operator to recognize a run-away and take [the appropriate corrective] action. Obviously, when the telescope is that low in the bay, and that happens, you have a concern that it is going to take longer to recognize and stop it than the [time and distance] you have. In order to protect for that failure, what they did was, through the software, to limit the amount of current that you can send to the motors and that way, if a motor failed on for some reason it would drive slowly enough that the operator, in principle at least, would be able to recognize that and take action before there was an impact.
That is what was planned for STS-31. Hawley could control the rate of motion, or drive, through the software. As he unberthed Hubble, the software load would be changed so that when he had lifted the payload high enough, greater current was sent to the motors slowing the rate down. But what happened on-orbit was that these loads became lost in the general noise of the system, to the extent that the signal noise that Hawley was sending from the controller to the arm was not that much bigger than the noise in the system. This combined noise then acted like a command, as far as the motors were concerned, confusing the system. Normally the ground simulators did not model this effect, and the crew didnt notice it until they were actually deploying Hubble. As Hawley explained, The consensus was, when I would command pure up motion, it wouldnt move purely up, it would wallow around. I remember that it was really confusing when it was doing that, because it wasnt the way it behaved in the sims and made the deployment task [about] 50 percent longer, because we kept having it stop and take out the commands that we werent requesting and the different axis [that the arm was heading in].
Once we came back after STS-31, Hawley continued, we went over to the Shuttle Engineering Simulator and we modeled the noise, and my recollection is that we very accurately reproduced what we saw in deployment. Ultimately, what we did was develop a control mode for the arm called POHS [pronounced POSH] for Position Orientation Hold Submode [in which] you could select that mode, then command in the minus Z orbiter axis, purely straight up out of the bay, with the software only allowing motion in that one axis. It would cancel out the noise in the system that we had on STS-31 that was trying to rotate the telescope in pitch and yaw, and send opposite commands. That made it quite a bit easier.
Hubble on the arm
The training for the mission had rehearsed a number of contingency and backup modes, including two worse-case scenarios that involved deploying the telescope in the backup mode and the total loss of the RMS. A failure of the orbiters Main Bus A or Manipulator Controller Interface Unit (MCIU) could disable all the modes reliant on software. It had also been found that in the event of a failure of the systems management general purpose computer this could be replaced by a guidance navigation and control computer in order to support the operation of the arm. Should it be required, the crew had trained to remove and replace a MCIU with a spare. The individual joint motors could be driven in the backup mode, but without computer support or information displays. Reflecting on these contingency procedures, Hawley wrote in 2014 that had such a failure occurred, it would have been preferable to have delayed the deployment of Hubble until the MCIU backup unit had been installed.
Although the Earth return mode for servicing needs had been abandoned in 1985 owing to the cost and the risk to the integrity of the telescope, the option for a contingency return was discussed in the event that Discovery was unable to attain the minimum deployment altitude. The overriding concerns which fuelled the decision to pursue orbital servicing remained, and as a result the team developed a means of deploying the telescope even if the RMS was not functional. This concept, which became known as backaway deploy, would have involved turning the orbiter to the tail-to-Sun attitude to allow the telescopes Sun sensors to lock onto the Sun after its release. The disconnection of the umbilical would then have been followed by the opening of the four payload retention latch assemblies. With Hubble essentially free of the orbiter, Discovery would then have flown out from under the telescope. During flight techniques meetings in 1989, the question of providing the procedures in the STS-31 flight plan were discussed several times. There were many issues to be resolved with this proposal, and of course if anything had gone wrong in the post-deployment period, such as the failure of solar array or high gain antenna deployment, there would have been very little the crew could have done without an operational RMS. In 2014 Hawley recalled that some standalone training was done in the shuttle mission simulator for this mode, but they did not progress to the integrated simulation level. The backaway deployment procedures were available on the checklists for the mission, but fortunately neither this nor any other contingency plans were needed in deploying the telescope.
Light
Font size:
↓
↑
Reset
Interval:
↓
↑
Bookmark:
Make
Similar books «The Hubble Space Telescope: From Concept to Success»
Look at similar books to The Hubble Space Telescope: From Concept to Success. We have selected literature similar in name and meaning in the hope of providing readers with more options to find new, interesting, not yet read works.
Christy Peterson
Kevin Hartnett
N Okamoto
Michael Soluri
Michael D. Cole
David Shayler
Reviews about «The Hubble Space Telescope: From Concept to Success»
Discussion, reviews of the book The Hubble Space Telescope: From Concept to Success and just readers' own opinions. Leave your comments, write what you think about the work, its meaning or the main characters. Specify what exactly you liked and what you didn't like, and why you think so.