Turtles

- floor robots

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floor turtle
'The Computerized Society'
Pizzy & Snowden, 1985.
As you can see, the original turtle is a small computer controlled robot. It moves around the floor on a flat sheet of paper, drawing a line as it goes.

It has two drive wheels, which are controlled independently.
When both wheels rotate in the same direction, the turtle moves back or forward in a straight line. If the wheels rotate in opposite directions, the turtle turns on the spot.

At the centre of the turtle is the pen. It can be raised or lowered. When lowered, a line is drawn as the turtle trundles along. When raised, no line is drawn.

Note that the pen is exactly between the two wheels. Hence no line is drawn when the turtle turns.

The turtle is completly unaware of its absolute location and heading. Drawing commands are carried out relative to the turtles current position and heading only.
floor turtle floor turtle
'A Guide To Using
Micro's In The Classroom'
Drage & Evans, 1988.
floor turtle
Roving floor turtle