Kids Web Japan

Groups of these driverless vehicles traveling together can avoid collisions just like fish swimming in schools

EPORO is an amazing new robot vehicle which was introduced at CEATEC JAPAN 2009 by the Japanese automaker Nissan Motor Co., Ltd. CEATEC JAPAN is an annual exhibition organized to introduce cutting-edge Japanese information technology (IT) and electronic products, and Nissan is a regular participant.

At the previous CEATEC exhibition (2008) Nissan exhibited the BR23C, a robot car with collision avoidance technologies modeled on the flight navigation behavior of bees. But the BR23C was designed to avoid obstacles while traveling alone. EPORO vehicles, by contrast, were developed to avoid obstacles—including each other—while traveling in groups. They were designed to mimic the navigation behavior of schools of fish.

EPORO is an acronym for EPisode O (Zero) RObot (an ‘episode’ designed to be CO2- and accident-free).

How do fish navigate in schools?

Fish can swim in a school without ever bumping into each other, even while they are all sharply maneuvering as a group to avoid underwater obstacles. Nissan very carefully analyzed this behavior, and identified three sets of rules governing it, all based on distance (see diagram below):

FISH BEHAVIOR RULES

Rule #1 (AREA 1): ‘Collision Avoidance’
—Change traveling direction without colliding with other fish.

Rule #2 (AREA 2): ‘Traveling Side-by-Side’
—Travel side-by-side with other fish while keeping a certain distance between each fish (to match the speed).

Rule #3 (AREA 3): ‘Approaching’
—Gain closer proximity to other fish that are too distant.

Having identified these rules, Nissan developed the EPORO vehicles to be able to follow them. Generally, to monitor their surroundings fish use their sense of sight, combined with a lateral line sense to ‘feel’ the distance between themselves and nearby objects. Nissan recreated these capabilities with sensors, a laser range finder, two-way communications, and other advanced electronic technologies. Thus EPORO vehicles avoid collisions while traveling in a fleet by informing each other of their positions.

This is the first time a robot vehicle with a collision-free group travel capability has been developed through the use of two-way communications technologies.

This diagram shows the three basic rules governing fish behavior:
Rule #1 (AREA 1): ‘Collision Avoidance’
Rule #2 (AREA 2): ‘Traveling Side-by-Side’
Rule #3 (AREA 3): ‘Approaching’

While swimming in schools fish never bump into each other, even while they are all sharply maneuvering as a group to avoid underwater obstacles.

EPORO represents a breakthrough technology that will open up new possibilities for the automobile

The technology employed by the collision-free robot car EPORO will contribute to the future development of safer vehicles, and safer streets, roads and highways. If vehicles moving in groups could be controlled, this would prevent traffic jams, making driving easier and more efficient. It would also prevent traffic accidents, which is something that all Japanese automakers would very much like to see.

Japanese automakers are famed for using their world-class technological capabilities to create innovative new vehicles such as electric cars, hybrid cars and hydrogen cars. But they are also continuously developing other advanced vehicles as well—especially vehicles which, like EPORO, promise ever greater safety for drivers and their passengers.

So that they can travel in groups without colliding just like schools of fish, EPORO vehicles use two-way communications to inform each other of their positions.

(Updated in January 2010)