Mexico City - About 467,000 people in Mexico are blind, but the lifetime cost of keeping a guide dog is estimated to cost around 300,000 pesos, a price that restricts their use for many Mexicans who are visually impaired.

But an electronic version might soon be available at a more affordable price.

A group of graduate students at Mexico's National Polytechnic Institute (IPN) have created their own version of a guide dog for the blind, a robot called Amepi that operates on three algorithms: one to evade obstacles, another that simulates a guide dog's behavior, and a third that recognizes signs in public places so it can advise the user of the location of washrooms, evacuation routes and safety zones.

Amepi employs ultrasound sensors to get around: when it senses it is approaching an obstacle it slows down and changes direction, simulating just what a guide dog would do - but its parts and software cost only about 15,500 pesos.

The robotic 'guide dog' is made of lightweight plastic and runs on caterpillar tracks. It is equipped with two cameras, a telescoping handle that adjusts to different heights, and is powered by 12 AA rechargeable batteries.

The project is still in prototype stage, so the three budding computer systems engineers who created Amepi — Francisco Javier García, Jessica Espinosa and Manuel Caballero — are looking for an investor to help fund the robot's optimization and development, the patent process, and its subsequent marketing.