13 June 2018 – Ever wonder why Kim Jong Un is so willing to talk about giving up his nuclear arsenal? Sort-of-President Donald Trump (POTUS) seems to think it’s because economic sanctions are driving North Korea (officially the Democratic People’s Republic of Korea, or DPRK) to the finacial brink.
That may be true, but it is far from the whole story. As usual, the reality star POTUS is stuck decades behind the times. The real World War III won’t have anything to do with nukes, and it’s started already.
The threat of global warfare using thermonuclear weapons was panic inducing to my father back in the 1950s and 1960s. Strangely, however, my superbrained mother didn’t seem very worried at the time.
By the 1980s, we were beginning to realize what my mother seemed to know instinctively — that global thermonuclear war just wasn’t going to happen. That kind of war leaves such an ungodly mess that no even-marginally-sane person would want to win one. The winners would be worse off than the losers!
The losers would join the gratefully dead, while the winners would have to live in the mess!
That’s why we don’t lose sleep at night knowing that the U.S., Russia, China, India, Pakistan, and, in fact, most countries in the first and second worlds, have access to thermonuclear weapons. We just worry about third-world toilets (to quote Danny DeVito’s character in The Jewel of the Nile) run by paranoid homicidal maniacs getting their hands on the things. Those guys are the only ones crazy enough to ever actually use them!
We only worried about North Korea developing nukes when Kim Jong Un was acting like a total whacko. Since he stopped his nuclear development program (because his nuclear lab accidentally collapsed under a mountain of rubble), it’s begun looking like he was no more insane than the leaders of Leonard Wibberley’s fictional nation-state, the Duchy of Grand Fewick.
In Wibberley’s 1956 novel The Mouse That Roared, the Duchy’s leaders all breathed a sigh of relief when their captured doomsday weapon, the Q-Bomb, proved to be a dud.
Yes, there is a hilarious movie to be made documenting the North Korean nuclear and missile programs.
Okay, so we’ve disposed of the idea that World War III will be a nuclear holocaust. Does that mean, as so many starry-eyed astrophysicists imagined in the late 1940s, the end of war?
Fat f-ing chance!
The winnable war in the Twenty-First Century is one fought in cyberspace. In fact, it’s going on right now. And, you’re missing it.
Cybersecurity and IT expert Theresa Payton, CEO of Fortalice Solutions, asserts that suspected North Korean hackers have been conducting offensive cyber operations on financial institutions amid discussions between Washington and Pyongyang on a possible nuclear summit between President Trump and Kim Jong Un.
“The U.S. has been able to observe North Korean-linked hackers targeting financial institutions in order to steal money,” she says. “This isn’t North Korea’s first time meddling in serious hacking schemes. This time, it’s likely because the international economic sanctions have hurt them in their wallets and they are desperate and strapped for cash.”
There is a long laundry list of cyberattacks that have been perpetrated against U.S. and European interests, including infrastructure, corporations and individuals.
“One of N. Korea’s best assets … is to flex it’s muscle using it’s elite trained cyber operations,” Payton asserts. “Their cyber weapons can be used to fund their government by stealing money, to torch organizations and governments that offend them (look at Sony hacking), to disrupt our daily lives through targeting critical infrastructure, and more. The Cyber Operations of N. Korea is a powerful tool for the DPRK to show their displeasure at anything and it’s the best bargaining chip that Kim Jong Un has.”
Clearly, DPRK is not the only bad state actor out there. Russia has long been in the news using various cyberwar tactics against the U.S., Europe and others. China has also been blamed for cyberattacks. In fact, cyberwarfare is a cheap, readily available alternative to messy and expensive nuclear weapons for anyone with Internet access (meaning, just about everybody) and wishing to do anybody harm, including us.
“You can take away their Nukes,” Payton points out, “but you will have a hard time dismantling their ability to attack critical infrastructure, businesses and even civilians through cyber operations.”
Programming Notes: I’ve been getting a number of comments on this blog each day, and it looks like we need to set some ground rules. At least, I need to be explicit about things I will accept and things I won’t:
First off, remember that this isn’t a social media site. When you make a comment, it doesn’t just spill out into the blog site. Comments are sequestered until I go in and approve or reject them. So far, the number of comments is low enough that I can go through and read each one, but I don’t do it every day. If I did, I’d never get any new posts written! Please be patient.
Do not embed URLs to other websites in comments. I’ll strip them out even if I approve your comment otherwise. The reason is that I don’t have time to vet every URL, and I stick to journalistic standards, which means I don’t allow anything in the blog that I can’t verify. There are no exceptions.
This is an English language site ONLY. Comments in other languages are immediately deleted. (For why, see above.)
Use Standard English written in clear, concise prose. If I have trouble understanding what you’re trying to say, I won’t give your comment any space. If you can’t write a cogent English sentence, take an ESL writing course!
23 May 2018 – Way back in the 1990s, during a lunch conversation with friends involved in the custom motorcycle business, one of my friends voiced the opinion that hand crafted items, from fine-art paintings to custom motorcycle parts, were worth the often-exhorbitant premium prices charged for them for two reasons: individualization and premium quality.
At that time, I disagreed about hand-crafted items exhibiting premium quality.
I had been deeply involved in the electronics test business for over a decade both as an engineer and a journalist. I’d come to realize that, even back then, things had changed drastically from the time when hand crafting could achieve higher product quality than mass production. Things have changed even more since then.
Early machine tools were little more than power-driven hand tools. The ancient Romans, for example, had hydraulically powered trip hammers, but they were just regular hammers mounted with a pivot at the end of the handle and a power-driven cam that lifted the head, then let it fall to strike an anvil. If you wanted something hammered, you laid it atop the anvil and waited for the hammer to fall on it. What made the exercise worthwhile was the scale achievable for these machines. They were much larger than could be wielded by puny human slaves.
The most revolutionary part of the Industrial Revolution was invention of many purpose-built precision machine tools that could crank out interchangeable parts.
Most people don’t appreciate that previously nuts and bolts were made in mating pairs. That is, that bolt was made to match that nut because the threads on this other nut/bolt pair wouldn’t quite match up because the threads were all filed by hand. It just wasn’t possible to carve threads with enough precision.
Precision machinery capable of repeating the same operation to produce the same result time after time solved that little problem, and made interchangeable parts possible.
Statistical Process Control
Fast forward to the twentieth century, when Walter A. Shewhart applied statistical methods to quality management. Basically, Shewhart showed that measurements of significant features of mass-produced anything fell into a bell-shaped curve, with each part showing some more-or-less small variation from some nominal value. More precise manufacturing processes led to tighter bell curves where variations from the nominal value tended to be smaller. That’s what makes manufacturing interchangeable parts by automated machine tools possible.
Before Shewhart, we knew making interchangeable parts was possible, but didn’t fully understand why it was possible.
If you’re hand crafting components for, say, a motorcycle, you’re going to carefully make each part, testing frequently to make sure it fits together with all the other parts. Your time goes into carefully and incrementally honing the part’s shape to gradually bring it into a perfect fit. That’s what gave hand crafting the reputation for high quality.
In this cut-and-try method of fabrication, achieving a nominal value for each dimension becomes secondary to “does it fit.” The final quality depends on your motor skills, patience, and willingness to throw out anything that becomes unsalvageable. Each individual part becomes, well, individual. They are not interchangeable.
If, on the other hand, you’re cranking out kazillions of supposedly interchangeable parts in an automated manufacturing process, you blast parts out as fast as you can, then inspect them later. Since the parts are supposed to be interchangeable, whether they fit together is a matter of whether the variation (from the nominal value) of this particular part is small enough so that it is still guaranteed to fit with all the other parts.
If it’s too far off, it’s junk. If it’s close enough, it’s fine. The dividing line between “okay” and “junk” is called the “tolerance.”
Now, the thing about tolerance is that it’s somewhat flexible. You CAN improve the yield (the fraction of parts that fall inside the tolerance band) by simply stretching out the tolerance band. That lets more of your kazillion mass-produced parts into the “okay” club.
Of course, you have to fiddle with the nominal values of all the other parts to make room for the wider variations you want to accept. It’s not hard. Any engineer knows how to do it.
However, when you start fiddling with nominal values to accommodate wider tolerances, the final product starts looking sloppy. That is, after all, what “sloppy” means.
By the 1980s, engineers had figured out that if they insisted on automated manufacturing equipment to achieve the best possible consistency, they could then focus in on reducing those pesky variations (improving precision). Eventually, improved machine precision made it possible to squeeze tolerances and remove sloppiness (improving perceived quality).
By the 1990s, automated manufacturing processes had achieved quality that was far beyond what hand-crafted processes could match. That’s why I had to disagree with my friend who said that mass-manufactured stuff sacrificed quality for quantity.
In fact, Shewhart’s “statistical process control” made it possible to leverage manufacturing quantity to improve quality.
That, however, left hand-crafting’s only remaining advantage to be individualization. You are, after all, making one unique item.
Hand crafting requires a lot of work by people who’ve spent a long time honing their skills. To be economically viable, it’s got to show some advantage that will allow its products to command a premium price. So, the fact that hand-crafting’s only advantage is its ability to achieve a high degree of product individualization matters!
I once heard an oxymoronic joke comment that said: “I want to be different, like everybody else.”
That silly comment actually has hidden layers of meaning.
Of course, if everybody is different, what are they different from? If there’s no normal (equivalent to the nominal value in manufacturing test results), how can you define a difference (variation) from normal?
Another layer of meaning in the statement is its implicit acknowledgment that everyone wants to be different. We all want to feel special. There seems to be a basic drive among humans to be unique. It probably stems from a desire to be valued by those around us so they might take special care to help ensure our individual survival.
That would confer an obvious evolutionary advantage.
One of the ways we can show our uniqueness is to have stuff that shows individualization. I want my stuff to be different from your stuff. That’s why, for example, women don’t want to see other women wearing dresses identical to their own at a cocktail party.
In a world, however, where the best quality is to be had with mass-produced manufactured goods, how can you display uniqueness without having all your stuff be junk? Do you wear underwear over a leotard? Do you wear a tutu with a pants suit? That kind of strategy’s been tried and it didn’t work very well.
Ideally, to achieve uniqueness you look to customize the products that you buy. And, it’s more than just picking a color besides black for your new Ford. You want significant features of your stuff to be different from the features of your neighbor’s stuff.
As freelance journalist Carmen Klingler-Deiseroth wrote in Automation Strategies, a May 11 e-magazine put out by Automation World, “Particularly among the younger generation of digital natives, there is a growing desire to fine-tune every online purchase to match their individual tastes and preferences.”
That, obviously, poses a challenge to manufacturers whose fabrication strategy is based on mass producing interchangeable parts on automated production lines in quantities large enough to use statistical process control to maintain quality. If your lot size is one, how do you get the statistics?
She quotes Robert Kickinger, mechatronic technologies manager at B&R Industrial Automation as pointing out: “What is new . . . is the idea of making customized products under mass-production conditions.”
Kickinger further explains that any attempt to make products customizable by increasing manufacturing-system flexibility is usually accompanied by a reduction in overall equipment effectiveness (OEE). “When that happens, individualization is no longer profitable.”
One strategy that can help is taking advantage of an important feature of automated manufacturing equipment, it’s programmability. Machine programmability comes from its reliance on software, and software is notably “soft.” It’s flexible.
If you could ensure that taking advantage of your malleable software’s flexibility won’t screw up your product quality when you make your one, unique, customized product, your flexible manufacturing system could then remain profitable.
One strategy is based on simulation. That is, you know how your manufacturing system works, so you can build what I like to call a “mathematical model” that will behave, in a mathematical sense, like your real manufacturing system. For any given input, it will produce results identical to that of the real system, but much, much faster.
The results, of course, are not real, physical products, but measurement results identical to what your test department will get out of the real product.
Now, you can put the unique parameters of your unique product into the mathematical model of your real system, and crank out as many simulated examples of products as you need to ensure that when you plug those parameters into your real system, it will spit out a unique example of your unique product exhibiting the best quality your operation is capable of — without the need of cranking out mass quantities of unwanted stuff in order to tune your process.
So, what happens when (in accordance with Murphy’s Law) something that can go wrong does go wrong? Your wonderful, expensive, finely tuned flexible manufacturing system spits out a piece of junk.
You’d better not (automatically) box that piece of junk up and ship it to your customer!
Instead, you’d better take advantage of the second feature Kickinger wants for your flexible manufacturing system: real-time rejection.
“Defective products need to be rejected on the spot, while maintaining full production speed,” he advises.
Immediately catching isolated manufacturing defects not only maintains overall quality, it allows replacing flexibly manufactured unique junk to be replaced quickly with good stuff to fulfill orders with minimum delay. If things have gone wrong enough to cause repetitive multiple failures, real-time rejection also allows your flexible manufacturing system to send up an alarm alerting non-automated maintenance assets (people with screwdrivers and wrenches) to correct the problem fast.
“This is the only way to make mass customization viable from an economic perspective,” Kickinger asserts.
Social and technological trends will only make developent of this kind of flexible manufacturing process de rigeur in the future. Online shoppers are going to increasingly insist on having reasonably priced unique products manufactured to high quality standards and customized according to their desires.
As Kickinger points out: “The era of individualization has only just begun.”
9 April 2018 – Last week turned out to be big for news about personal transportation, with a number of trends making significant(?) progress.
Let’s start with a report (available for download at https://gen-pop.com/wtf) by independent French market-research company Ipsos of responses from more than 3,000 people in the U.S. and Canada, and thousands more around the globe, to a survey about the human side of transportation. That is, how do actual people — the consumers who ultimately will vote with their wallets for or against advances in automotive technology — feel about the products innovators have been proposing to roll out in the near future. Today, I’m going to concentrate on responses to questions about self-driving technology and automated highways. I’ll look at some of the other results in future postings.
Perhaps the biggest take away from the survey is that approximately 25% of American respondents claim they “would never use” an autonomous vehicle. That’s a biggie for advocates of “ultra-safe” automated highways.
As my wife constantly reminds me whenever we’re out in Southwest Florida traffic, the greatest highway danger is from the few unpredictable drivers who do idiotic things. When surrounded by hundreds of vehicles ideally moving in lockstep, but actually not, what percentage of drivers acting unpredictably does it take to totally screw up traffic flow for everybody? One percent? Two percent?
According to this survey, we can expect up to 25% to be out of step with everyone else because they’re making their own decisions instead of letting technology do their thinking for them.
Automated highways were described in detail back in the middle part of the twentieth century by science-fiction writer Robert A. Heinlein. What he described was a scene where thousands of vehicles packed vast Interstates, all communicating wirelessly with each other and a smart fixed infrastructure that planned traffic patterns far ahead, and communicated its decisions with individual vehicles so they acted together to keep traffic flowing in the smoothest possible way at the maximum possible speed with no accidents.
Heinlein also predicted that the heros of his stories would all be rabid free-spirited thinkers, who wouldn’t allow their cars to run in self-driving mode if their lives depended on it! Instead, they relied on human intelligence, forethought, and fast reflexes to keep themselves out of trouble.
And, he predicted they would barely manage to escape with their lives!
I happen to agree with him: trying to combine a huge percentage of highly automated vehicles with a small percentage of vehicles guided by humans who simply don’t have the foreknowledge, reflexes, or concentration to keep up with the automated vehicles around them is a train wreck waiting to happen.
Back in the late twentieth century I had to regularly commute on the 70-mph parking lots that went by the name “Interstates” around Boston, Massachusetts. Vehicles were generally crammed together half a car length apart. The only way to have enough warning to apply brakes was to look through the back window and windshield of the car ahead to see what the car ahead ofthem was doing.
The result was regular 15-car pileups every morning during commute times.
Heinlein’s (and advocates of automated highways) future vision had that kind of traffic density and speed, but were saved from inevitable disaster by fascistic control by omniscient automated highway technology. One recalcitrant human driver tossed into the mix would be guaranteed to bring the whole thing down.
So, the moral of this story is: don’t allow manual-driving mode on automated highways. The 25% of Americans who’d never surrender their manual-driving priviledge can just go drive somewhere else.
Yeah, I can see THAT happening!
A Modest Proposal
With apologies to Johnathan Swift, let’s change tack and focus on a more modest technology: driver assistance.
Way back in the 1980s, George Lucas and friends put out the third in the interminable Star Wars series entitled The Empire Strikes Back. The film included a sequence that could only be possible in real life with help from some sophisticated collision-avoidance technology. They had a bunch of characters zooming around in a trackless forest on the moon Endor, riding what can only be described as flying motorcycles.
As anybody who’s tried trailblazing through a forest on an off-road motorcycle can tell you, going fast through virgin forest means constant collisions with fixed objects. As Bugs Bunny once said: “Those cartoon trees are hard!”
Frankly, Luke Skywalker and Princess Leia might have had superhuman reflexes, but their doing what they did without collision avoidance technology strains credulity to the breaking point. Much easier to believe their little speeders gave them a lot of help to avoid running into hard, cartoon trees.
In the real world, Israeli companies Autotalks, and Griiip, have demonstrated the world’s first motorsport Vehicle-to-Vehicle (V2V) application to help drivers avoid rear-ending each other. The system works is by combining GPS, in-vehicle sensing, and wireless communication to create a peer-to-peer network that allows each car to send out alerts to all the other cars around.
So, imagine the situation where multiple cars are on a racetrack at the same time. That’s decidedly not unusual in a motorsport application.
Now, suppose something happens to make car A suddenly and unpredictably slow or stop. Again, that’s hardly an unusual occurrance. Car B, which is following at some distance behind car A, gets an alert from car A of a possible impending-collision situation. Car B forewarns its driver that a dangerous situation has arisen, so he or she can take evasive action. So far, a very good thing in a car-race situation.
But, what’s that got to do with just us folks driving down the highway minding our own business?
During the summer down here in Florida, every afternoon we get thunderstorms dumping torrential rain all over the place. Specifically, we’ll be driving down the highway at some ridiculous speed, then come to a wall of water obscuring everything. Visibility drops from unlimited to a few tens of feet with little or no warning.
The natural reaction is to come to a screeching halt. But, what happens to the cars barreling up from behind? They can’t see you in time to stop.
So, coming to a screeching halt is not the thing to do. Far better to keep going forward as fast as visibility will allow.
But, what if somebody up ahead panicked and came to a screeching halt? Or, maybe their version of “as fast as visibility will allow” is a lot slower than yours? How would you know?
The answer is to have all the vehicles equipped with the Israeli V2V equipment (or an equivalent) to forewarn following drivers that something nasty has come out of the proverbial woodshed. It could also feed into your vehicle’s collision avoidance system to step over the 2-3 seconds it takes for a human driver to say “What the heck?” and figure out what to do.
The Israelis suggest that the required chip set (which, of course, they’ll cheerfully sell you) is so dirt cheap that anybody can afford to opt for it in their new car, or retrofit it into their beat up old junker. They further suggest that it would be worthwhile for insurance companies to give a rake off on their premiums to help cover the cost.
Sounds like a good deal to me! I could get behind that plan.
30 March 2018 – Mobile autonomous systems come in all sizes, shapes, and forms, and have “invaded” every earthly habitat. That’s not news. What is news is how far the “bleeding edge” of that technology has advanced. Specifically, it’s news when a number of trends combine to make something unique.
Today I’m getting the chance to report on something that I predicted in a sci-fi novel I wrote back in 2011, and then goes at least one step further.
Last week the folks at Design World published a report on research at the MIT Computer Science & Artificial Intelligence Lab that combines three robotics trends into one system that quietly makes something I find fascinating: a submersible mobile robot. The three trends are soft robotics, submersible unmanned systems, and biomimetic robot design.
The beasty in question is a robot fish. It’s obvious why this little guy touches on those three trends. How could a robotic fish not use soft robotic, sumersible, and biomemetic technologies? What I want to point out is how it uses those technologies and why that combination is necessary.
Folks have made ROVs (basically remotely operated submarines) for … a very long time. What they’ve pretty much all produced are clanky, propeller-driven derivatives of Jules Verne’s fictional Nautilus from his 1870 novel Twenty Thousand Leagues Under the Sea. That hunk of junk is a favorite of steampunk afficionados.
Not much has changed in basic submarine design since then. Modern ROVs are more maneuverable than their WWII predecessors because they add multiple propellers to push them in different directions, but the rest of it’s pretty much the same.
Soft robotics changes all that.
About 45 years ago, a half-drunk physics professor at a kegger party started bending my ear about how Mommy Nature never seemed to have discovered the wheel. The wheel’s a nearly unique human invention that Mommy Nature has pretty much done without.
Mommy Nature doesn’t use the wheel because she uses largely soft technology. Yes, she uses hard technology to make structural components like endo- and exo-skeletons to give her live beasties both protection and shape, but she stuck with soft-bodied life forms for the first four billion years of Earth’s 4.5-billion-year history. Adding hard-body technology in the form of notochords didn’t happen until the cambrian explosion of 541-516 million years ago, when most major animal phyla appeared.
By the way, that professor at the party was wrong. Mommy Nature invented wheels way back in the precambrian era in the form of rotary motors to power the flagella that propel unicellular free-swimmers. She just hasn’t use wheels for much else, since.
Of course, everybody more advanced than a shark has a soft body reinforced by a hard, bony skeleton.
Today’s soft robotics uses elastomeric materials to solve a number of problems for mobile automated systems.
Perhaps most importantly it’s a lot easier for soft robots to separate their insides from their outsides. That may not seem like a big deal, but think of how much trouble engineers go through to keep dust, dirt, and chemicals (such as seawater) out of the delicate gears and bearings of wheeled vehicles. Having a flexible elastomeric skin encasing the whole robot eliminates all that.
That’s not to mention skin’s job of keeping pesty little creepy crawlies out! I remember an early radio astronomer complaining that pack rats had gotten into his remote desert headquarters trailer and eaten a big chunk of his computer’s magnetic-core memory. That was back in the days when computer random-access memories were made from tiny iron beads strung on copper wires.
Another major advantage of soft bodies for mobile robots is resistance to collision damage. Think about how often you’re bumped into when crossing the room at a cocktail party. Now, think about what your hard-bodied automobile would look like after bumping into that many other cars in a parking lot. Not a pretty sight!
The flexibility of soft bodies also makes possible a lot of propulsion methods beside wheel-like propellers, caterpillar tracks, and rubber tires. That’s good because piercing soft-body skins with drive shafts to power propellers and wheels pretty much trashes the advantages of having those skins in the first place.
That’s why prosthetic devices all have elaborate cuffs to hold them to the outsides of the wearer’s limbs. Piercing the skin to screw something like Captain Hook’s hook directly into the existing bone never works out well!
So, in summary, the MIT group’s choice to start with soft-robotic technology is key to their success.
Submersible Unmanned Systems
Underwater drones have one major problem not faced by robotic cars and aircraft: radio waves don’t go through water. That means if anything happens that your none-too-intelligent automated system can’t handle, it needs guidance from a human operator. Underwater, that has largely meant tethering the robot to a human.
This issue is a wall that self-driving-car developers run into constantly (and sometimes literally). When the human behind the wheel mandated by state regulators for autonomous test vehicles falls asleep or is distracted by texting his girlfriend, BLAMMO!
The world is a chaotic place and unpredicted things pop out of nowhere all the time. Human brains are programmed to deal with this stuff, but computer technology is not, and will not be for the foreseeable future.
Drones and land vehicles, which are immersed in a sea of radio-transparent air, can rely on radio links to remote human operators to help them get out of trouble. Underwater vehicles, which are immersed in a sea of radio-opaque water, can’t.
In the past, that’s meant copper wires enclosed in physical tethers that tie the robots to the operators. Tethers get tangled, cut and hung up on everything from coral outcrops to passing whales.
There are a couple of ways out of the tether bind: ultrasonics and infra-red. Both go through water very nicely, thank you. The MIT group seems to be using my preferred comm link: ultrasonics.
Sound goes through water like you-no-what through a goose. Water also has little or no sonic “color.” That is, all frequencies of sonic waves go more-or-less equally well through water.
The biggest problem for ultrasonics is interference from all the other noise makers out there in the natural underwater world. That calls for the spread-spectrum transmission techniques invented by Hedy Lamarr. (Hah! Gotcha! You didn’t know Hedy Lamarr, aka Hedwig Eva Maria Kiesler, was a world famous technical genius in addition to being a really cute, sexy movie actress.) Hedy’s spread-spectrum technique lets ultrasonic signals cut right through the clutter.
So, advanced submersible mobile robot technology is the second thread leading to a successful robotic fish.
Biomimetics is a 25-cent word that simply means copying designs directly from nature. It’s a time-honored short cut engineers have employed from time immemorial. Sometimes it works spectacularly, such as Thomas Wedgwood’s photographic camera (developed as an analogue of the terrestrial vertebrate eye), and sometimes not, such as Leonardo da Vinci’s attempts to make flying machines based on birds’ wings.
Obvously, Mommy Nature’s favorite fish-propulsion mechanism is highly successful, having been around for some 550 million years and still going strong. It, of course, requires a soft body anchored to a flexible backbone. It takes no imagination at all to copy it for robot fish.
The copying is the hard part because it requires developing fabrication techniques to build soft-bodied robots with flexible backbones in the first place. I’ve tried it, and it’s no mean task.
The tough part is making a muscle analogue that will drive the flexible body to move back and forth rythmically and propel the critter through the water. The answer is pneumatics.
In the early 2000s, a patent-lawyer friend of mine suggested lining both sides of a flexible membrane with tiny balloons that could be alternately inflated or deflated. When the balloons on one side were inflated, the membrane would curve away from that side. When the balloons on the other side were inflated the membrane would curve back. I played around with this idea, but never went very far with it.
The MIT group seems to have made it work using both gas (carbon dioxide) and liquid (water) for the working fluid. The difference between this kind of motor and natural muscle is that natural muscle works by pulling when energized, and the balloon system works by pushing. Otherwise, both work by balancing mechanical forces along two axes with something more-or-less flexible trapped between them.
In Nature’s fish, that something is the critter’s skeleton (backbone made up of vertebrae and stiffened vertically by long, thin spines), whereas the MIT group’s robofish uses elastomers with different stiffnesses.
Putting these technical trends together creates a complete package that makes it possible to build a free-swimming submersible mobile robot that moves in a natural manner at a reasonable speed without a tether. That opens up a whole range of applications, from deep-water exploration to marine biology.