What purpose does a cape serve in a superhero’s wardrobe? Usually nothing except fashion.
In Batman Begins however, we are shown that a cape can do more than make you look like a cheap magician. Bruce Wayne uses some fancy materials called memory cloth to turn his cape from a floppy fashion accessory into a stiff glider with the application of an electric charge. I’m sure the gritty nature of this movie required the writers to throw this in to justify giving the Dark Knight what would otherwise look like a frivolous ornament.
But even worse than looking silly, a cape can be deadly! One of the greatest scenes from The Incredibles where Edna talks about the unfortunate costume designs of doomed supers, AKA “No capes!”
Even Watchmen hits on this theme when it shows the violent demise of Dollar Bill after he gets stuck in a revolving door.
So how could you balance the utility with the inconvenience of a long flowy piece of fabric? Fold it up when you don’t need it! Nature is full of examples of reversible folding. When leaves appear in the spring, they don’t just grow very quickly. They are fully formed in the bud, and then unfurl all at once when the timing is right.
Mathematicians, physicists, and engineers have started noticing these intricate packaging patterns in biological materials and trying to apply them to their own work. The Japanese art of origami has had a resurgence not just among artists, but also scientists as a way to discover new folds and test designs. One cool application of origami-science has been realized in the deployment of solar panels for space vessels.
And I think the greatest thing we’ve gotten out of studying folding is figuring out how to make it easy and reversible! Umbrellas partially demonstrate this idea since they have two stable states and always fold and unfold in the same predictable pattern, but they need quite a bit of force to transition. The people in this video demonstrate how easy it is to fold and unfold a design named the Miura-ori. The most important part is that we’re going between something map-sized and something that will fit in your pocket in a matter of seconds.
Insects are masters of reversible folding with their wings. Beetles are one of the best examples because they need to transition between flying and walking so frequently. When they walk on the ground, they risk their wings getting caught or damaged, so they tuck them neatly under a protective shell until they need to fly again.
And this is exactly the mechanism I propose for superheroes that actually use capes for flight or protection! Fold it up, and then deploy it on demand. This, by the way, is most of the premise of the short-lived NBC series The Cape.
Heroes could possibly even keep their entire costume folded up for a speedy wardrobe change during a crisis. Peter Parker’s backpack could unfurl into Spidey-spandex, or Superman could carry around his own collapsible phone booth for privacy on the go. These are kind of silly examples, but think of all the other ways you could make life easier with simple repeatable folding patterns. Sky divers need professionals to pack up their parachutes correctly, but what if it was designed so you could fold it yourself? A pop-up tent that fits in a small bag would be great for long hikes, or getting emergency shelters to disaster-stricken areas quickly and efficiently. Strollers and all of those other baby furniture accessories could definitely be improved if they could be packed into the car that much faster. Problem-solving by paper-folding!
Besides martial arts expertise and a strong sense of justice of course.
Batman is all about advancing technology through his super-cool gadgetry, so it’s no surprise that he adapted a highly useful remote sensing technique from his namesake animal.
Bats, along with several other species of mammals, birds, and odontocetes, use sound to navigate their surroundings and find prey. Bats produce a series of ultrasonic clicks, and then listen to the echoes to conceptualize their environment. Sound is reflected in different ways depending on the texture of the surface it bounces off of, and the echo qualities can also estimate the size of the target object. The small differences between what is heard in each ear allow the animals to pinpoint locations precisely and detect if something's moving, what direction it's moving in, and how fast. Sound like a familiar human invention?
SONAR = SOund Navigation And Ranging
The physical principles behind echolocation have been adapted into sonar technology used in submarines to detect other subs and whatever else is in the water. Considering that echolocation in animals was theorized more than a century before the invention of sonar, it's likely that there was a certain amount of bioinspiration involved. It was also used to sense objects in the air before radar was developed. Radar is a generally superior remote sensing system because radio waves move faster than sound waves, but sonar still remains in use underwater because the radar's emitted microwaves are rapidly absorbed by water.
Passive sonar was the first system employed in underwater detection, and it worked by listening in on well-placed hydrophones. It’s called passive because the hydrophones are only receiving sounds made by other things without producing any sounds themselves. It was a subpar arrangement since it depended on a quiet ocean while you hoped that what you were looking for was noisy, which might not always be the case. World War II compelled developers to raise the level of the technology and gave us active sonar. Now subs were sending out their own *pings* (the ones you’ve surely heard in Das Boot or The Hunt for Red October) and using the echoes in a manner closer to bats. The technology is also used frequently today to map the ocean floor through multibeam swath bathymetry.
Batman uses both active and passive forms of sonar in The Dark Knight when he turns every cell phone in Gotham into a microphone. The phones have become active high frequency sound generators (akin to the ultrasonic clicks of microbats), and they also passively detect sounds outside of that range. Thanks to their built in GPS, he knows exactly where every sound is coming from. Lucius Fox of Wayne Enterprises monitors the console displaying all of the sonar data to help Batman narrow in on the Joker’s location, which is accomplished by comparing a sample of the Joker's voice to all of the incoming noise. Batman takes his batty-ness a step further by projecting the sonar-created images onto the lenses built into his cowl. So even though it's pitch dark, he can use sound pictures to guide his way and find the bad guys.
But even humans that aren’t billionaire crime fighters have taken advantage of this technology for personal use! Some blind people have, through direct biomimicry, learned how to use echolocation themselves. For example, this documentary from the UK series Extraordinary People features a teenager who had his eyes removed at the age of three to prevent the spread of retinal cancer. The video is long, but watching the first few minutes will give you the idea.
Ben Underwood is not only capable of walking around without a cane or a guide dog, but he’s actually quite proficient at biking, rollerblading, and skateboarding! He achieves this by constantly clicking at his surroundings and listening to the way the clicks bounce back. He can’t reach the high frequencies that dolphins and bats use, but it gets the job done. Unfortunately, Ben died in 2009 as a result of his cancer.
Daniel Kish is also featured in the video, and another person rendered blind by retinal cancer who has learned to use echolocation instead of a cane. He is president of World Access for the Blind and teaches children how to navigate an unfamiliar environment using sound.
Cool connection to the comic book world: another blind echolocator, Juan Ruiz, appeared in the first episode of Stan Lee’s Superhumans where he demonstrated his super abilities to navigate and measure the length of a cave. It’s an excellent show for investigating the possibilities of superpowers in our mortal realm!
Now, comic book fans, another superhero may be coming to mind:
Daredevil was made blind by toxins that, through some comic-induced happenstance, enhanced the rest of his senses. He is often described as having a “radar-like sense,” but much of it can actually be attributed to passive sonar. His enhanced hearing allows him to identify and position objects in space. To get an idea of how powerful his ears were, he was purportedly able to hear the Hulk’s heartbeat from four blocks away. So much like these humans, he has compensated for his lack of sight by using other means to explore his environment. I don’t think any of them adapted their white canes to serve as a billy club though.
Exploring the realm of biologically inspired design one superhero example at a time, with some other natural sciences mixed in.