Robots and Roundabouts

My wheels screech around the curve of the roundabout as I accelerate to create a space for the Volvo preparing to enter the circle. I ease up as I see the car up ahead in the road prepare to exit out of the circle. I am doing my best to adapt to those around me, monitoring my nearest neighbors and trying to conform to their behavior. Like any good swarm robot, I am balancing their goals and initiative with my own as I careen along the busy English roads.

It turns out the roundabout was invented by a pioneering American who campaigned hard for the US to adopt them, but eventually gave up and shifted to Europe. I love the efficiency of flying right through intersections without having to wait at lights or stop for stop signs. To me it seems effortless to interact with my peers on the road. My American business partner in the passenger seat disagrees. She hates roundabouts and doesn’t understand why anyone would want all the stress: “It’s so much harder to know what to do and requires so much skill.” I ask if she would rather have to sit and wait at a light to which she immediately answers in the affirmative. “Oh definitely! It’s much easier because you know exactly what to do. Besides I don’t trust other drivers.”

And there you have it. We have two different impulses that underly our world. One craves strong central leadership and depends on clear rules and enforcement. The other seeks interdependence. To those in the first camp, dependence on others seems weak or even dangerous. After all, do you really want to trust that driver who is holding his cellphone in one hand, while turning around to talk to his kids in the backseat? To the other camp, interdependence is a source of strength, allowing each member of the swarm to adapt and conform not only to each other, but to the environment and situation.

I think back to one of my first efforts to map out chemical hazards. The task involved sending robots into a DOE facility to find a spill. The little bots are equipped with small chemical sensors under their belly. They also have speakers, hearing aid microphones and infrared break beams that allow them to talk to their peers. Once they reach the spill, they will stop in place to mark the perimeter. While individual robots are single-minded in their purpose, the swarm as a whole must explore and eventually transcribe the perimeter. I need a way to push them out and around the spill. The bots are not given maps because we don’t have them and they cannot build a map because that would require more sophisticated computers and sensors. Instead, these bots are equipped with a desire to distance themselves from one another. They use the infrared break-beams, but they also use a more biologically inspired approach that involves chirping to one another. The relative volume of the microphones on each robot helps them know where their neighbors are.

When I first release the swarm of twelve robots into the DOE facility they spin and turn like mad, abruptly switching direction as they see their peers in close proximity. They are programmed to seek open space so they will fan out. Crammed in like sardines at the start, they respond to each other at first frenetically, but they are not mindless and quickly adapt and most soon find clear space. Some of them are caught in a labyrinth of piping and the default parameters are not working well for this dense environment. Each of them in their own time individually recognizes a lack of progress and becomes willing to adapt behavioral parameters. The robots are not intelligent, but they do know when they are stuck or flailing. They are constantly willing to change strategy.

The swarm robots are being supervised by a sergeant robot that is much larger. Junior weighs several hundred pounds whereas his little ducklings weigh less than a pound each. The larger robot has a camera so it can send video back to the human operators and that video should show were the spill has spread. DOE personnel watching through the video feed point out which robots seem courageous and which seem timid, although they are not programmed for emotion. Their behavior is the emergent effect of the code that motivates them. Of course, the same could be said of human behavior. We learn and adapt our original code as we interact with the environment and our peers. My experience with robots indicates that swarm behavior tends to be more adaptive, resilient and efficient, but even in robotics most people are in the first camp – they want robots to be rule followers. For some, it is a matter of control. If we let robots make their own decisions and learn who knows what they will do? Their behavior can’t be guaranteed... just like the drivers in a roundabout. The problem is that if we withhold agency, robots can’t take part in the drama of real-world adaptation and problem solving.

Neither choice is without risk. Perhaps it is not a question of which is a better choice, but rather of which world we want to live in. We cannot guarantee safety with either, but we do know which one is more adaptive and flexible. The swarm approach is more resilient. Have you ever been in a large city when the power goes out? When all those traffic lights stop working, we see swarm behavior emerge. Slowly, tentatively, people shake off the need for rule-based control. They venture out into the intersection waiting to see if the other drivers coming towards them are going to stop. It’s an exercise in trust and it gives many people the heebie-jeebies. When a traffic light sensor is not working correctly, how long do you sit there unwilling to take initiative? Instead of moving forward with caution we remain stuck in place, waiting for centralized control to tell us what to do. Some of us live our whole lives this way. At these times, we seem like dumb robots… Not the agile, adaptive swarm robots, but rather the other kind of automation – the kind that can’t really help you because it isn’t allowed to adapt the rules or solve problems. Rule breaking can be a problem, but sometimes an overzealous desire for rule following can be downright terrifying. Sometimes we need to channel our inner swarm robot, becoming willing to make mistakes, depart from the plan and adapt on the fly.