On Thursday, a portion of the 12-story Champlain Towers South condominium building in Surfside, Florida (just outside of Miami) suffered a catastrophic partial collapse. As of Saturday morning, according to the Miami Herald, 159 people are still missing, and rescuers are removing debris with careful urgency while using dogs and microphones to search for survivors still trapped within a massive pile of tangled rubble.
It seems like robots should be ready to help with something like this. But they aren’t.
A Miami-Dade Fire Rescue official and a K-9 continue the search and rescue operations in the partially collapsed 12-story Champlain Towers South condo building on June 24, 2021 in Surfside, Florida.JOE RAEDLE/GETTY IMAGES
The picture above shows what the site of the collapse in Florida looks like. It’s highly unstructured, and would pose a challenge for most legged robots to traverse, although you could see a tracked robot being able to manage it. But there are already humans and dogs working there, and as long as the environment is safe to move over, it’s not necessary or practical to duplicate that functionality with a robot, especially when time is critical.
What is desperately needed right now is a way of not just locating people underneath all of that rubble, but also getting an understanding of the structure of the rubble around a person, and what exactly is between that person and the surface. For that, we don’t need robots that can get over rubble: we need robots that can get into rubble. And we don’t have them.
To understand why, we talked with Robin Murphy at Texas A&M, who directs the Humanitarian Robotics and AI Laboratory, formerly the Center for Robot-Assisted Search and Rescue (CRASAR), which is now a non-profit. Murphy has been involved in applying robotic technology to disasters worldwide, including 9/11, Fukushima, and Hurricane Harvey. The work she’s doing isn’t abstract research—CRASAR deploys teams of trained professionals with proven robotic technology to assist (when asked) with disasters around the world, and then uses those experiences as the foundation of a data-driven approach to improve disaster robotics technology and training.
According to Murphy, using robots to explore rubble of collapsed buildings is, for the moment, not possible in any kind of way that could be realistically used on a disaster site. Rubble, generally, is a wildly unstructured and unpredictable environment. Most robots are simply too big to fit through rubble, and the environment isn’t friendly to very small robots either, since there’s frequently water from ruptured plumbing making everything muddy and slippery, among many other physical hazards. Wireless communication or localization is often impossible, so tethers are required, which solves the comms and power problems but can easily get caught or tangled on obstacles.
Even if you can build a robot small enough and durable enough to be able to physically fit through the kinds of voids that you’d find in the rubble of a collapsed building (like these snake robots were able to do in Mexico in 2017), useful mobility is about more than just following existing passages. Many disaster scenarios in robotics research assume that objectives are accessible if you just follow the right path, but real disasters aren’t like that, and large voids may require some amount of forced entry, if entry is even possible at all. An ability to forcefully burrow, which doesn’t really exist yet in this context but is an active topic of research, is critical for a robot to be able to move around in rubble where there may not be any tunnels or voids leading it where it wants to go.
And even if you can build a robot that can successfully burrow its way through rubble, there’s the question of what value it’s able to provide once it gets where it needs to be. Robotic sensing systems are in general not designed for extreme close quarters, and visual sensors like cameras can rapidly get damaged or get so much dirt on them that they become useless. Murphy explains that ideally, a rubble-exploring robot would be able to do more than just locate victims, but would also be able to use its sensors to assist in their rescue. “Trained rescuers need to see the internal structure of the rubble, not just the state of the victim. Imagine a surgeon who needs to find a bullet in a shooting victim, but does not have any idea of the layout of the victims organs; if the surgeon just cuts straight down, they may make matters worse. Same thing with collapses, it’s like the game of pick-up sticks. But if a structural specialist can see inside the pile of pick-up sticks, they can extract the victim faster and safer with less risk of a secondary collapse.”
Besides these technical challenges, the other huge part to all of this is that any system that you’d hope to use in the context of rescuing people must be fully mature. It’s obviously unethical to take a research-grade robot into a situation like the Florida building collapse and spend time and resources trying to prove that it works. “Robots that get used for disasters are typically used every day for similar tasks,” explains Murphy. For example, it wouldn’t be surprising to see drones being used to survey the parts of the building in Florida that are still standing to make sure that it’s safe for people to work nearby, because drones are a mature and widely adopted technology that has already proven itself. Until a disaster robot has achieved a similar level of maturity, we’re not likely to see it take place in an active rescue.
Keeping in mind that there are no existing robots that fulfill all of the above criteria for actual use, we asked Murphy to describe her ideal disaster robot for us. “It would look like a very long, miniature ferret,” she says. “A long, flexible, snake-like body, with small legs and paws that can grab and push and shove.” The robo-ferret would be able to burrow, to wiggle and squish and squeeze its way through tight twists and turns, and would be equipped with functional eyelids to protect and clean its sensors. But since there are no robo-ferrets, what existing robot would Murphy like to see in Florida right now? “I’m not there in Miami,” Murphy tells us, “but my first thought when I saw this was I really hope that one day we’re able to commercialize Japan’s Active Scope Camera.”
The Active Scope Camera was developed at Tohoku University by Satoshi Tadokoro about 15 years ago. It operates kind of like a long, skinny, radially symmetrical bristlebot with the ability to push itself forward:
The hose is covered by inclined cilia. Motors with eccentric mass are installed in the cable and excite vibration and cause an up-and-down motion of the cable. The tips of the cilia stick on the floor when the cable moves down and propel the body. Meanwhile, the tips slip against the floor, and the body does not move back when it moves up. A repetition of this process showed that the cable can slowly move in a narrow space of rubble piles.
“It's quirky, but the idea of being able to get into those small spaces and go about 30 feet in and look around is a big deal,” Murphy says. But the last publication we can find about this system is nearly a decade old—if it works so well, we asked Murphy, why isn’t it more widely available to be used after a building collapses? “When a disaster happens, there’s a little bit of interest, and some funding. But then that funding goes away until the next disaster. And after a certain point, there’s just no financial incentive to create an actual product that’s reliable in hardware and software and sensors, because fortunately events like this building collapse are rare.”
Dr. Satoshi Tadokoro inserting the Active Scope Camera robot at the 2007 Berkman Plaza II (Jacksonville, FL) parking garage collapse.Photo: Center for Robot-Assisted Search and Rescue
The fortunate rarity of disasters like these complicates the development cycle of disaster robots as well, says Murphy. That’s part of the reason why CRASAR exists in the first place—it’s a way for robotics researchers to understand what first responders need from robots, and to test those robots in realistic disaster scenarios to determine best practices. “I think this is a case where policy and government can actually help,” Murphy tells us. “They can help by saying, we do actually need this, and we’re going to support the development of useful disaster robots.”
Robots should be able to help out in the situation happening right now in Florida, and we should be spending more time and effort on research in that direction that could potentially be saving lives. We’re close, but as with so many aspects of practical robotics, it feels like we’ve been close for years. There are systems out there with a lot of potential, they just need all help necessary to cross the gap from research project to a practical, useful system that can be deployed when needed.
Evan Ackerman is a senior editor at IEEE Spectrum. Since 2007, he has written over 6,000 articles on robotics and technology. He has a degree in Martian geology and is excellent at playing bagpipes.