Perhaps most important was the cost. The standard type of solar panel fabric was made in rectangular sheets. Material for a rectangular sail would be almost an off-the-shelf item. For the circular sail, the solar panel material had to be cut into arc slices like pieces of pie, which meant additional cost for custom sail parts. The change in cost wasn’t small, either. There were virtually no other customers ordering pie slice-shaped solar panels and all the costs for development, setup, and fabrication had to be borne by one customer (their lightship project) and by the first set of sails. The difference in cost between rectangular and arc sections of sail material was nearly a factor of five. Although the sails were not the most expensive part of the ship, no part of the ship was cheap and the change in cost alone was dramatic enough to call into question the original idea of circular solar sails that opened like fans.
It turned out that the engineering of the new system was also easier to understand. The new system was quite similar to an electrically driven horizontal window shade and there were plenty of those around to look at and play with. There were some differences in the solar sails to be sure, but the fundamentals were similar. For a while there were window shades hanging in frames decorating the entire engineering department.
The new design consisted of two large rectangles, each forty meters high and twenty-five meters wide, for an area of a bit over two thousand square meters when both sails were completely unfurled. The newest variety of panel fabric was lightweight, sturdy, and highly efficient, and two thousand square meters would generate over one megawatt of power. Each sail was a frame of metal tubing that formed the edges of the sail, with strips of solar fabric running across the width of the frame. The old sailboat terminology still stuck; the team called the long vertical tubes masts and the short tubes that formed the top and bottom of the sail its spars. In addition to the spars at the top and bottom, there was a spar in the middle of each long section of sail. The center spar broke each sail in two and contained additional “up” and “down” motors, so that there were four sails that could be independently operated, two on each side of the ship’s hull.
Sheets of solar fabric were fastened together in long rolls, with cabling at the top of each section of a standard width of solar fabric. Small motors at the top and bottom of each sail were used to roll up or pull down a solar window shade. (Motors had to pull down and draw up the window shade; there was no gravity to pull the sails down.) When the solar sails were inactive they were rolled up into a cylinder at the “top” of the two top sails and at the “bottom” of the bottom sails; when they were deployed to generate electricity they rolled out to form a flat surface between the top and bottom of each sail frame. A series of cables running from each rollup cylinder of each sail carried electric current to the inside mast where it was routed to the ship’s systems and the plasma engines
Behind each layer of solar panel fabric was a second layer of power generating fabric. The second layer was made of a special material that absorbed the waste heat from the solar panels and turned a portion of that heat into more electricity. The combination of fabrics lifted the conversion efficiency of the sails considerably, providing more electricity while keeping the light converting solar fabric cooler. As the operating theory was that the ship should keep its sails in full sunlight as much as possible, anything that kept the sails cooler was a real benefit.
Arturo showed Kevin the updated rectangular design on his computer display. “It looks like this design will actually be quite a bit better than the one with the half-moon sails. It’s heavier, but the cost is almost certain to be lower and the ship’s sails are likely to wear longer. We can also do a better job of managing the heat in the engines and cooling system because we can furl and unfurl the panels quite frequently without putting a lot of stress on them. We’ll lose some cargo capacity due to the added weight, but we’ll almost certainly save money on construction and wear and tear.”
Kevin watched the three-dimensional view on Arturo’s design station as it rotated slowly on the screen. “How much additional weight?”
“We think about a ton because of the motors and the increased weight of the masts. That’s an upper limit, though; it could be quite a bit less if we can keep the weight of the masts and spars down.”
Kevin nodded. “Okay, let’s run it through the trip simulators to see how things work. We have the option of hiding in the shade of the earth and the Moon to cool off the system on a trip to the Moon, but that will make our trip time longer and our navigation kind of tricky. We’ve already got storage batteries, but they won’t last long. I’d like to be able to run her in full sun, above the shadow of the earth if possible. It would be nice to have that capability when we start thinking about trips to Venus as well.
“We need the updated figures on weight, too. Every pound we have to put into the ship is a pound of cargo we can’t carry.”
“Okay, boss. I think we’ll be okay with this design. Are you going to update Klaus on the change?”
Kevin nodded again. “Yeah, but it will be brief. The savings in costs will make him happy and I’ll try to keep him away from the loss of cargo weight. Right now I think anything that saves money on the ship’s construction will be okay with him.”
The Lunar Compact
In the year since his first meeting with the Secretary General, Danny had politicked his way across more small- to medium size nations than he cared to count, promoting his (actually the Secretary General’s) draft of a constitution for the Moon. He carried the draft with him everywhere, looking for support from the Secretary General’s list of potential signatories, checking in to other possible supporters, asking for suggestions and listening to problems. In retrospect the draft constitution seemed to hold up well under scrutiny. People took it seriously and made thoughtful suggestions, some of which made their way in to revisions. Even though he was the one pushing the draft he was somewhat amazed at how many of the nations he visited seemed to approve and were willing to back it up. The Secretary General’s plan had worked; he had agreements in principle from twenty nations. He thought he could turn those agreements into reality, especially once the first ship made a run.
He talked things over with Chaz, partially to make sure he wasn’t missing anything while making sure his director was properly informed.
“I think I understand the reasoning behind the general reaction. From the viewpoint of the less powerful nations in the U.N., the Lunar Compact gives them a chance to wedge themselves and possibly the rest of the world into what has been the nearly exclusive province of a small number of powerful nations. It should also help to reduce the threat of open warfare between nations who want a piece of the lunar pie. That was the most significant of my concerns. It looks as though the work and the Secretary Genera’s ideas are were going to pay off.”
Chaz nodded. “Anything that reduces the possibilities of violence on the Moon is a good thing. It would be all too easy for one of the big players here on Earth to get upset if there wasn’t some kind of global mechanism for calling them out in case of a conflict up there. The Compact makes it hard for anyone who isn’t happy to just start shooting up there.”
“It’s kind of funny that the big players didn’t take the Compact seriously. The situation on the Moon has been like the Korean armistice- a loaded gun that could go off any time somebody gets really unhappy.
In our favor, though, the current crop of spacefaring nations hasn’t taken the project seriously. They think I’m nuts or just plain foolish. No one thinks there’s any reason to spend always-scarce national resources on a sustained effort up there.”
“It’s pretty weird. As far as we can tell no one has even tried to evaluate Kevin’s work. Our potential competitors are all busy making money on their satellite businesses.
“In a strange way the Compact has contributed camouflage for the ship; the space nations are focused on the political issues and have been unconcerned about the progress of the project. They seem
to think our objective of protecting a lunar colony is a big waste. There weren’t any colonies now; they themselves weren’t planning any, so why bother?”
Danny laughed. “Yep, no one seems to care. I think they won’t care until we’re up there planting a Smith Interplanetary flag on the best real estate up there. Then there will be a mad rush to be second, just because the public has had expectations for the huge space funding requests that haven’t delivered. There will be politicians panicking all over the globe.”
The smile disappeared.
“Things haven’t been all rosy, though. This job, getting the draft in the hands of the right nations, has taken much more of my time than I really wanted to spend. An time that’s still being spent.
“The push also hasn’t been much fun, either. While we get points for developing visibility with a lot of governments, there hasn’t been any direct return on investment. The businesses have suffered because I haven’t been around, and they may suffer further if I can’t cut shorten up this job.
Chaz asked, “Is there anything we can do to cut down on the workload for you?”
“Sure. Get me an announcement in the immediate future. Then I can declare victory and get the Compact published so the big boys have got behave like we’ve beaten them to the punch. How close are we?”
Chaz replied, “The first ship is nearly ready, as are the drones. Klaus thinks the first test run to the Moon will happen in the next month or two. And the drones that are going to do our exploring on the surface are about ready too.”
“Good. When the drone explorers are on their way I want to get the Lunar Compact portrayed to the public as more than a piece of paper. Once out in the open, it should be hard for any latecomers to seize any of the sites we’re interested in without generating a hell of a lot of bad press.”
“Do you think that will be enough? We won’t actually have any stations on the Moon for a while yet.”
Danny shrugged. “I sure hope so. I’ve got to get the politics wrapped up, and the best way to do that is to generate a lot of “we’ve got a tent on the Moon publicity.
“After that I can get our group of nations together to establish some sort of government for the Moon, publicize the agreement, and arrange for some security to be on the Moon as soon as the civilian research station is inhabited.
Chaz looked worried. “All of this will cost money and time. You aren’t burning through as much of personal assets that you’ll would lose control of any of the businesses, but we still have to keep things moving. The outflow is likely to increase as soon as the Foundation (or maybe one of his corporations?) starts shipping people up for long-term stays. It’s pretty certain that we’ll have some research grant money coming in, but especially in the early days it won’t be enough to cover expenses. We have to get things wrapped up soon and start cutting costs, or find additional sources of funding to bear some of the burden.”
Danny looked out the window of his office. “Yeah. I just hope there’s something up there worth all this trouble.”
Drone Space
The drone drivers entered the new control room and took a look around. The room itself wasn’t much; empty except for a series of ten workstations that looked like they belonged in a game arcade.
Arturo Sanchez, better known as Artie to Kevin and his engineers, stopped the group in front of the first workstation. Artie led the engineering teams of the project- one that worked on the ship itself, and one that worked on support, including the drones that were going to do final assembly of the lightship in Earth orbit.
The operator positions were comfortable shells with some isolation from each other. Each faced a bank of monitors dedicated to the management of a single drone. Each drone needed the support of two workstations. Eight workstations controlled four drones; the last two were supervisory stations that could take control of any given drone if need be, but whose primary functions were to coordinate multi-drone activities and manage the overall workflow.
“In this room, you people will learn how to operate the drones that will build the space dock, do final assembly of the ships as parts come up from the ground, and do in-dock maintenance by remote control once the ships are flying.
“Over the next two months you will work with simulations of the actual drones while the machines themselves are still being completed and taken into orbit. You will have the chance to try the drones on a simulated space dock and a simulation of the first ship. During this time, you will be helping to identify and resolve any problems that arise in the beta versions of the drone hardware and software. Once the drones are finished and sent into orbit, the workstations will switch out of the simulations into live operations in space.
“Your first task is to learn the basics of drone handling. Next you will begin the practical planning of assembly in space, starting with construction of the space dock and planning of the construction of the ship in the alpha version simulation. You can expect your learning experiences to be iterative- what you learn in drone handling will affect the planning of your construction projects, and what you learn in construction will affect what you need to know and how you go about assembling the dock and the first ship.
“Your experiences in the alpha simulations will lead into the development of beta procedures, as well as recommendations for needed changes to the space dock and the ship kit. Then beta feedback will be applied to a production simulation. Once the production simulation is finalized, we will run performance tests on the ship and space dock designs. If all goes well during the performance tests, we’ll begin to go live with the hardware phase of the project.
“We’re hoping that that the production simulations will deal with one hundred percent of the real in-space procedures that you will have to execute via your drones, as well as a goodly portion of any unexpected contingencies. That may be a lot to ask, but we don’t want to have to make big changes once the project goes into orbit. If that happens, the cost of the project will go up quickly and the chances of failure will go up just as fast.
“Any questions?” Artie looked at all of his new drone drivers, but there was silence.
“Okay then. Let’s get you started. Your accounts have already been authorized to access the driving stations. Four of you will do the driving, and four will try out the manipulation routines.”
In addition to building the space dock and the ship, two of the four drones would be carried on the ship to be used for some regular and all emergency maintenance. Some of the drone drivers would learn the basics of drone operation to enable them to operate the drones during voyages. For the cargo carrier, all of the human crew would work from Earth; the ship’s artificial intelligence system and the drones would be the crew for the trips to Moon orbit. The AI would learn drone driving as well; to the extent possible the cargo ships were going to be automated. The human crew would return to action when the ship dropped its first “passengers” from orbit onto the surface of the Moon. The ship’s passengers would be a set of four drones, customized for landing and exploration of the lunar environment. The explorers were one-way actors. They would land as a group via a rocket-powered frame and break off to start their exploration. As with Earth’s gravity well, this was a spot where standard, high-impulse rocket motors were needed.
After the drone teams were sorted out and assigned stations, Artie had everyone cluster around one of the supervisor stations. The supervisor station had somewhat more powerful software than the drone drivers. It had things like cursor controls to allow an instructor to point at things on the screen outside of the actual operator simulations, as well as videos of various preliminary simulations that had been developed alongside the drone development process. He spoke to the various functions and demonstrated functions and drone driving basics as he talked.
“Each construction drone is controlled by a “mover” workstation and a “handler” workstation.” He flipped pushed a button on his control wheel, changing the view to the default visual of each kind of stati
on.
“The leftmost station in line here is the first mover station; the next station is the handler for the same drone. Drivers and movers are alternated down the line; drivers on the left; handlers on the right, with the last two stations being supervisors that can easily switch from driver to handler. In a pinch we can double up functions on a single drone station, both mover and handler for the same drone. We’d rather not do that unless there’s a failure of some sort. If possible we’ll take a supervisor station and bring it online to fill the gap. For the regular workstation It takes some time to flip between mover and handler views, and splitting up screens to different functions is kind of a hassle.
“Both mover and handler workstations have ten video screens, each of which cover sixty degrees of vision horizontally and sixty degrees vertically. If there is a failure of one or more displays, the remaining displays can take up the visual task by compressing their original view and adding in the view that has been lost in the failure. If the software is failing, we have a tougher time making a fix. It may be necessary to use another workstation’s view to shut down the affected drone and its associated workstations until a repair or a bug fix is completed.
“The tenth screen at the top of the array is a rear view mirror, giving the drivers just enough information about things behind the drone to minimize accidents. Through the nine forward-looking views, the human controller can view a full one hundred eighty degrees of horizontal space and one hundred eighty degrees of vertical space. Again, that’s sixty degrees horizontally and vertically on each display. The tenth screen is connected to a wide-angle camera on the reverse side of each drone. The idea here is to give you as much view of the area behind a drone as possible without adding a lot of additional cost or overtaxing a driver with information that might interfere with their forward-looking control.
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