Turtles are a class of educational
robots designed originally in the late 1940s (largely under the auspices of researcher
William Grey Walter) and used in
computer science and
mechanical engineering training. These devices are traditionally built low to the ground with a roughly hemispheric (sometimes transparent) shell and a power train capable of a very small
turning radius. The robots are often equipped with
sensor devices which aid in avoiding obstacles and, if the robot is sufficiently sophisticated, allow it some perception of its environment. Turtle robots are commercially available and are common projects for robotics hobbyists. Turtle robots are closely associated with the work of
Seymour Papert and the common use of the
Logo programming language in computer education of the 1980s. Turtles specifically designed for use with Logo systems often come with pen mechanisms allowing the programmer to create a design on a large sheet of paper. The original Logo turtle, built by Paul Wexelblat at
BBN, was named "Irving" and was demonstrated at the former Muzzey Junior High in
Lexington, Massachusetts. "Irving" contained
bump sensors and could give audio feedback with a bell. The development of the robotic Logo turtle led to the use of the term to describe the
cursor in video screen implementations of the language and its
turtle graphics package.