“That’s how your basic visuals work. Now for controls.
“There are pedal controls for forward and backward acceleration (no such thing as gliding to a stop in space; if you want to stop you have to decelerate). A steering wheel enables you to turn right or left; pushing the wheel forward causes the drone to nose “down” from its position, while pulling back will turn the drone “up.” Up was defined as moving into the drone’s primary headlight beams; down moved the drone into the light from two smaller headlight beams on the bottom of the drone.
“We tried to simplify controls by requiring you to point the front of the drone in the direction you want to go. Thus, if you want to go toward the drone’s head, you pull out on the wheel and point the cameras fixed on the drone up. Sort of the way an airplane works, except that with our drones we want you to get them pointed in the right direction before you hit the accelerator.
“There are also controls for two tether reels on the right and left side of each drone. The tethers have hooks and electromagnetic pads at the ends to fasten a drone in place, both to keep the drone relatively motionless while working and to keep a drone from escaping away into space in case of an accident. For right now, we’ll focus on the basics of drone driving and handling. We’ll get into the skill of tether usage once you all have a better grasp on drone motion.
Artie flipped the switch on his station and converted the view to that of the handler.
“The handler workstation has a similar visual setup with nine video screens, but the controls consist primarily of two sets of two gloves each that the operator uses to control the motion of four manipulators on a drone. The “big” manipulators are near the center of the drone on opposite sides of the body. The two “small” manipulators are set close to one another at the front of the drone top (or “head”).” He waggled the drone’s hands, as if the drone was waving. That brought a bit of laughter from the group.
“An operator can grasp, move, and handle parts of the ship kit. These manipulators are first rate technology, one set enabling the operator to grasp and move large, heavy objects such as a plasma engine and the second set capable of manipulating small parts that required fine motor coordination like screws and other small fasteners. Within some limits the large manipulators can also be used to pull the drone around the ship or the space dock. Between the mover and handler operators, you will have control over two different forms of locomotion for your drone- maneuvering jets to cover distances and position a drone quickly and manipulators to pull the drone along the space dock or parts of the ship for short distances. You actually have a third means of locomotion with the tethers, but we’ll leave that for the tether discussion later on.
“The drones propel themselves by jetting water steam from nozzles arrayed around the frame of the drone. Water is heated by electricity from a small solar sail, as well as pure sunlight when the drone is in sun. A small battery pack keeps a drone operable when sunlight is not available. On a long day out of the sun you’ll have to track your batter usage; you don’t want to run out of power during an operation.
“You can control speed by releasing more or less steam through the drone’s jets, but the jets are limited to prevent an operator from overaccelerating. The two tethers, the ends of which can be fastened to the ship or the space construction dock that the ship and its parts are clamped to, also limits drone motion. The tethers ensure that the drones can’t fly off uncontrolled in case of an accident or malfunction. The tethers are retractable, and proper procedure is to have at least one tether attached to the ship assembly or the space dock at all times. During the start of your training sims, though, we’ll let you fly without a tether for a couple of lessons. Just so you get to see what happens if you don’t anchor your drone properly.
“In a nearly frictionless, zero gravity environment like space, it’s easy to forget that a little push will go a very long way. It’s easy to forget that objects moving in space won’t stop unless they are stopped by a force equal to and opposing the force that started them moving in the first place. Inexperienced drone drivers (like you) are very likely to use too much speed and force to get to a position, especially one at some distance from the drone’s starting point. They are also very likely to make braking mistakes by using too little or too much braking force.”
He flipped back to the driver display, pointing the drone toward a rudimentary animation of the space dock, and stepping on the accelerator for a short time. Then he took his hands and feet away from controls and let the drone crash into the dock, which caused the entire dock to begin to float away and spin out of control.
“Don’t forget that if you don’t compensate for your momentum in the drone, whatever you hit will have your momentum transferred to it. So a little mistake can get big pretty quickly in space. And it’s not just the force of the blow. It’s the direction, too. In the example I just showed you, my drone hit the dock at some place other then its center of gravity. Not only did the drone give the dock a shove based its own direction of motion, it applied torque around the center of gravity. So now we have a space dock that’s moving when it shouldn’t be, with a spin added that makes it even harder to stabilize.
One of the new drivers raised her hand. “If forgetting to stop is so bad, can’t some kind of error correction be added to the software?”
“An excellent question. Actually, you’ll find that your options have limits when you move the drone. It’s not going to move as fast as you might like, to keep the drone’s momentum down. That helps to make any accidents relatively innocuous. You will also find that if you don’t slow down adequately after putting a drone in motion toward a target, the drone control system will give you a collision warning, which is a pretty obnoxious sounding thing, and might even apply the brakes itself if it has to.
“You shouldn’t rely too much on the automated safety systems to save your drone. If our systems think you are doing too many stupid things, your drone just might stop obeying your commands and motor itself back to its sleeping spot on the dock, where it will stay until you get recertified as a drone driver or someone else takes over from you.”
The young woman who asked the question looked a little unsettled. “Um, okay. Thanks.”
Artie looked around at the drone team. “Any other questions? Okay, then I’ll continue. Please don’t be afraid to ask questions. Remember, the only dumb question is the one you don’t ask.
“Our development team attempted to deal with maneuvering issues in a very video game-like way, both to reduce the amount of time and fuel it takes to position a drone while reducing the likelihood of collisions with the ship, the space dock, or another drone. The operator can set the drone in “automatic” mode, in which the drone handles all the calculations to start, maneuver and stop itself to get to the desired location.
“The mover operator can set a target on an object by rotating the drone and setting a gun sight on the object. The operator then presses the Calculate button on the joystick; the drone brain calculates the distance to the object and the force vectors needed to get the drone to the object.”
Everyone watched as Artie rolled the drone around to put the gun sight on a portion of the simulated space dock. It took a little doing; he overshot his planned target the first time and had to slowly back up to get it lined up. That was a little worrisome to the engineer. He hadn’t noticed that before in the simulations. He wondered if it was a software problem.
“Speed is not controlled by the operator in automatic mode; the drone calculates a speed it thinks is appropriate to the distance, taking into consideration the availability of fuel. If you’re satisfied with the parameters calculated by the drone, you press a button on the joystick to execute the move. The drone fires its steam jets to get going, and then fires a reversing set when the drone is within the drone manipulators’ reaching distance. All of this is done by the drone’s brain. In the process the tethers are automatically reeled in or out to minimize tangling.
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sp; The process is a little cumbersome but it should reduce the likelihood of human error in positioning, as well as ensuring that the operator doesn’t forget to tether the drone. To the extent possible the drones do their own “housekeeping” to maximize the efficiency of the operator. At least, that’s the plan.”
Another hand went up. “You said something about steam. Is that how the drone is propelled?”
“Yes. The drones are refueled with water near the boiling point at the dock. Once the tank is full, the drone takes over and uses its solar panels and or battery power to get the heat up past boiling point. The steam is directed through a number of nozzles to push the drone in whichever direction the operator chooses.” He used the cursor to point at a meter in the simulated control panel. “This section of the control panel tells you how much water and steam is available to move the drone. When the meters go yellow, you should start thinking about returning the drone to its dock location to refuel. If it goes red, you’re within minutes of going dry. There’s a little bit of surplus in the tank when you get condition red, but I wouldn’t fiddle around hoping you can get a few things done before you take the drone back. We’d rather not have drones towing other drones around because somewhat didn’t take the time to fuel up.”
Another hand went up. “It seems like the guy driving the drone doesn’t have a lot to do. Is it really necessary to have two people operate one drone? Couldn’t a person just sort of switch modes, driving to get someplace then switching to do the work? Or using your automatic mode to minimize the amount of driving an operator has to do?”
“We thought about that. At this point we think the redundancy is justified. We’re starting with the basics of driving, but don’t think that’s all the driver (or as you’ll see, the handler for that matter) just deals with the drone. All of the stuff that will be in space is expensive, and costs go up dramatically if mistakes are made. You’re going to be spending a lot of time figuring out how to do things safely, using a full-size model of the ship. Once we get started, the job will not only require knowledge of the drone, but project planning to make sure each task is done safely and done right.”
Drone Problems
Lucy slammed the joystick forward, causing the simulated drone to spin head over heels. As the drone wasn’t real, the only thing the slam did was cause the view on the displays to roll as if the camera was attached to a ball. She needed something to throw and there wasn’t anything available.
“Damned rotten little teapot!”
Kevin pinched his nose, trying to relieve the tension brought on by one of his cousin’s temper tantrums. He hadn’t planned on hiring his cousin even though they needed someone in the programming area. Family forces being what they were, however, he had relented and brought Lucy on board. He had her starting out as a drone driver, to get her oriented on their user needs in the drone area.
As good as she was (and she was a good developer) she had a temper, one that tended to show up in verbal abuse of whoever or whatever was the source of her frustration. He restrained himself and did his best to ask a calm, meaningful question.
“What’s wrong, Lucy? Is there something we should look at?”
“Yes, dammit! Every time I try to line something up the jets aren’t calibrated closely enough and the stupid teapot drifts past my target! Worse, the tiny little difference between the two brake jets causes the stupid drone to turn. I can’t get the drone lined up enough to pull the trigger to get the damned thing moving in the right direction!”
He looked over at Arturo, who motioned him over with a pained look on his face. Kevin took the couple of steps over to Artie’s station. He asked quietly, “Is she right?”
Artie shrugged. “She has a point. The drone simulations work but it takes a lot of time to line a drone up on a target. If the calibration of the jets is just a little off it gets to be a real pain to line a drone up and get it moving in the right direction. Something has to be done; the drones will be out in space where we can’t just go out and replace or recalibrate pairs of jets.”
“Are you sure this isn’t something in the simulations, rather than the drones themselves?”
“The guys checked the simulation software. They’re pretty sure it’s a real flaw in the drone design. They checked the design of the steam jets and with no friction and no gravity it doesn’t take much of a difference to cause the drone to slide past or undershoot the target.”
“Well, what are you going to do?’ yelled Lucy. “I’m not going to spend my drone time jockeying one of the little bastards around. We need an effing solution!”
Kevin made a conciliatory motion with his hands, hoping he could quiet Lucy down a bit. “Okay, Lucy, okay. We’ll take a look at the design of the drones to see what we can do. We get the point. They’re hard to maneuver with the jets. Arturo and I will get together with the drone engineers to see what can be done. We’ll review the procedures manual too; there might be something we can do to help the drone drivers guide them. Why don’t you take a break, relax a little, and try running through some manipulator scenarios at one of the handler stations?” He looked at the rest of the trainees in the drone room. “I think it’s best if everyone takes an early lunch. Work at the manipulator stations when you come back. Team up and take turns running the scenarios. And if anyone has any ideas to improve handling of the drones, feel free to share them with Arturo or me.”
A Drone Fix
“Okay, Art, let’s hear it. Can we fix the drone design?”
Arturo nodded. “Yeah, Kevin, it can be done. We’ve run a couple of designs through the simulators and the best one works really well. The only problem is that none of the workable designs are modifications. It’s actually a brand new drone. At least half, maybe more of the original design is being replaced.”
Kevin looked stricken. “Oh, man. So we just threw away a bunch of money on a bad design and we’re going to have to go to the drone builders and tell them to start over?”
Arturo nodded again. “Pretty much. The drone guys aren’t going to be real happy, but on the plus side we caught this early. And it won’t be that bad. They’ll grumble in front of us but they’ll think about the extra cash flow and the pain will go away. The guys that are putting up the money, though…” He left the punch line unsaid.
Kevin frowned and wiped a hand across his forehead. “Man. They’ve been good about the money so far, but this one’s going to hurt. There’s no way we can fix the old design?”
“Not really. We looked at it and it’s pretty fatally flawed. We just didn’t realize how close the tolerances had to be on the jets to ensure that the push and the brake forces were identical. The jets work for a while, but they don’t wear evenly. That’s why they start to turn the drone. The only good thing about this is that the simulations let us catch the problem early instead of getting drones up in space and finding out they didn’t work then.”
“How does the new system work?”
“It’s pretty simple, really. In the old model the operator maneuvers the drone around to get the sight set on the destination. In the new system, the only thing that moves before the operator pulls the trigger is a sighting camera. The drone stays stationary until the operator executes the move. The drone can be completely out of sync with the camera. The drone does its own reorientation as part of the process of getting to the target. Then the guidance software kicks in and monitors the drone path, making whatever adjustments are necessary as it moves. The operator doesn’t have to fly the drone; it flies itself.”
“That’s great! Why didn’t we design the drones that way in the first place?”
Arturo shrugged. “There are some tradeoffs. The programming is more complex now; it’s not just about figuring out how much force is needed to launch and stop. It’s more expensive, too, both for the software and the drones themselves. Now the cameras have to be able to rotate, elevate, and decline separate from the drone. The engineering is tricky because we have to counterbalance any camera m
otion to hold the drone steady until the operator is ready to go. We didn’t think the original design would cause the operators as much trouble lining up the drone as they’ve had.”
“Yeah. Well, I’d better go tell Klaus. He’s not going to be happy.”
Arturo looked shocked. “You mean you haven’t told him yet?”
“I didn’t want to take him a technical problem until we had a solution.” Kevin shrugged. “I hate telling him that we’ve got a problem we don’t know how to fix. He gets you in range with those beady eyes and it feels like he’s drilling a hole in your head with them.”
“Well, better you than me. I sure wouldn’t wait any longer.” Arturo looked thoughtful. “I’ll get on the phone with the drone builders. He’s going to want costs. The sooner we get him those the better.”
“Right. Get them to me as soon as you’ve got something.” Kevin sighed. “I’ll go talk to Klaus now.”
**
Klaus looked at Kevin with a stony, thin-lipped expression. “Do you have a cost for me?”
Kevin shook his head. “Not yet. Arturo is going to get me a rough from the robotics company as soon as he can. He’s probably on the phone now.”
“You’re sure we have a fix?”
“Arturo says they ran a number of options through the simulators and the one the engineers have selected is far superior to the old system. It will save a lot of time in training and during actual operations, which should help to counterbalance the redesign costs. It’s going to cost up front, though. He says there’s no way to fix the old design. They have to throw away half or more of the original.”
Klaus turned away from Kevin. “Once Arturo gets the rough have him call me. I want to be involved in the negotiation of the final cost to us. Let’s not allow the drone fabricator to go wild with our money.”
They stood in silence for a few moments. Kevin had the feeling he hadn’t yet been dismissed.
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