International Science Consortium Investigates "Touch Technologies"

February 26, 2008

Based on principles of active sensing used widely in the animal kingdom, scientists from several nations have come together to investigate innovative possibilities of touch technologies. The result could be a whiskered “robotic rat” that would be looked upon kindly by humans.

The international consortium is delving into the ways in which rats, for example, use their bristly whiskers to explore their environment, and how the brain processes such information. A so-called whiskered robotic device could find applications in rescue missions, search missions under conditions of limited visibility, as well as in planetary research.

“The use of touch in the design of artificial intelligence systems has been largely overlooked, until now,” said Ehud Ahissar (Weizmann Institute of Science). “If we succeed in understanding what makes an animal’s sense of touch so efficient, we will be able to develop robots imitating this feature, and put them to effective use," said Ahissar.

As a rat's whiskers move back and forth, they gather information about the environment. Experiments have shown that the ways in which rats use their whiskers is context-dependent, that is, the  act of feeling a three-dimensional object requires three different types of code, each encoding a different dimension: the horizontal, the vertical, and the radial (distance from the whisker base).

The horizontal plane is encoded in the precise timing of neural signals relative to the whisking motion. The vertical is encoded by the vertical spacing of the whiskers, which are arranged grid-like on each side of the snout. The radial plane is encoded in the number of times the neurons fire: The closer an object is to the rat’s snout, the higher the number of neuron-signaling spikes.

The consortium’s research suggests that signals travel from the whiskers through parallel pathways that function within parallel closed feedback loops. “In order to investigate the role of feedback loops further consortium members will implement theoretical methods and calculations from theoretical physics and applied mathematics in order to develop and research models that describe the complicated neural processes that control active sensing,” said David Golomb (Ben Gurion University).

Their models are based on experimental observations. “Implementing them,” said Ahissar, "will hopefully allow robotics researchers to build machines that are more efficient, which can be used in rescue missions, as well as search missions under conditions of restricted visibility.”

The project, called BIOTACT, involves scientists from universities, research institutes, and high-tech companies in Britain, Israel, Switzerland, Italy, France, Germany, and the U.S.

Source: Newswise