It’s not everyday that you see a fingertip-sized robot, but you’ll find several examples in this interesting list.

Picobot

According to “poorrobot”, Picobot is the world’s smallest robot. Unfortunately, technical specifications haven’t yet been released.

Ants

Created at MIT’s Artificial Intelligence Lab, Ants are “a community of cubic-inch microrobots” designed “to push the limits of microrobotics by integrating many sensors and actuators into a small package. Each robot has 17 sensors including; four light sensors, four IR (infrared) receivers, bump sensors, food sensors, and a tilt sensor. They communicate with each other using two IR emitters, one mounted on the front of the robot and one mounted on the top.”

There are several levels of social behavior before reaching the goal of the ant colony. Right now, the robots can play Follow the Leader, Tag and Manhunt. Manhunt is similar to tag except there are two teams. The final game before the full-fledged Ant Farm is Capture the Flag. There are many application for robotic communities, including explosive ordnance disposal, and Mars exploration

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i-Sobot

Standing just 6.6-inches tall, the i-Sobot boasts a servo motor, 17 actuators for movement, and “can be controlled via a LCD-equipped remote control to perform pre-programmed actions.”

It can play music, dance, respond to voice commands for performing simple actions, respond to applause and other user actions and even play drums. Takara Tomy is also working on the Omnibot2007 i-SOBOT CamVersion which will come with a 300k pixel camera so it can transmit photos to your PC or Phone using Wi-Fi and a swiveling head with an angle of 60 degrees

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Worm

Inspired by polychaetes, this tiny worm robot “could one day help doctors diagnose disease by carrying tiny cameras through patients’ bodies”.

A robot designed to crawl through the human gut by mimicking the wriggling motion of an undersea worm has been developed by European scientists.

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Wristwatch

Robots just keep getting smaller and the “Eco-Be!” by Citizen is no exception. This nifty gadget is driven by a wristwatch motor and controlled via infared remote. It’s powered by normal watch batteries and has quad-directional movement. Measuring just 1.8 cm wide and 2.5 cm tall, it’s the perfect cubicle companion.

“Citizen president Makoto Umehara says he hopes Eco-Be! will prove useful in the development of smaller and lighter weight robots.”

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