What to do when the GPS on your phone is being wonky and you have no clue where you’re going? If these scientists have their way, there may be an alternative to find the fastest route to your destination: a totally analog GPS that works by using the age-old laws of chemistry.
The “chemical computing” system is admittedly a bit less practical than even those frustrating Garmins, but it could work faster than traditional satellite-based navigation. It’s already has been used to find the fastest route to a pizza restaurant in the city of Budapest.
To set it up, the scientists first created a maze that looks like a map of the area and includes start and end points. They filled it with an alkaline liquid, and at the exit of the labyrinth (i.e. the destination), placed a gel mixed with an acid. The acid slowly spread around the maze, but most of it stayed at the exit. Next, they mixed another alkaline solution with a colored dye and added it to the maze’s starting point. The starting point solution automatically moved towards the place with the highest acidity, i.e. the exit of the maze.
Swiss Federal Laboratories for Materials Science and Technology Rita Toth, a co-author of the study, explains that a chemical computer is more efficient than an electronic one because it finds all possible routes in parallel. While the dye mostly moves via the fastest route from start to finish, some of it also moves along other, less efficient routes. “A normal computer calculates step-by-step one possibility after another, which takes longer,” she writes in a press release.
It’s not the first time scientists have tested alternative systems to design or discover new routes. When scientists arranged oat flakes in the pattern of Japanese cities, for example, single-celled slime molds built nutrient channels in a pattern similar to the Japanese rail system. In that work, according to Wired, the scientists believed the slime mold’s behavior could help design more efficient, adaptable transportation networks.
The chemical computer team, which also included researchers in Hungary, Japan, and Scotland, is now creating larger, more complex mazes and eventually hopes the system could be useful in transportation planning and other fields. Already, however, the Budapest pizza navigation was a proof-of-concept in the real world.
The study was published in the journal Langmuir in June.