The traveling salesman problem is a problem in which the salesman visits the designated city once each and guides the shortest route out of the traveling routes back to the departure city. This mathematical problem, called the "combinatorial optimization problem," is related to various social issues such as logistics delivery planning and work schedule creation.However, it is difficult to solve with a conventional digital computer, and in recent years, proposals by quantum computers and the like have been made one after another.However, there was the problem that it was difficult to convert the problem into a format that the machine could handle.

　Unicellular slime mold, an amebic organism, has a high degree of computational ability to transform an amorphous body into an optimal shape for the environment.Previous research has shown that a "viscous computer" incorporating amoebic organisms can be used for the traveling salesman problem.Therefore, the research group has developed a new computer "Electronic Amoeba" that reproduces the mechanism of amoeba deformation by the movement of electrons in an analog circuit and can compactly express constraints such as urban layout and distance.As a result, we succeeded in quickly finding a solution to the traveling salesman problem.Compared with the typical algorithm (2-opt method) that solves this problem, the more cities there are, the more advantageous the electronic amoeba is in the solution search.

　An electronic amoeba that reproduces the search ability acquired by living things with an electronic circuit can contribute to solving difficult problems in the real world where constraints and demands continue to change.Furthermore, it is expected to realize a new principle computer that is small and has low power consumption that can be embedded in IoT devices.

Paper information:[Scientific Reports] Amoeba-inspired analog electronic computing system integrating resistance crossbar for solving the traveling salesman problem