The device, named Comp*pass, uses a mechanism similar to how traditional compass is used to draw a circle. Nakagaki told Dezeen that the original concept came from a sense of feeling curious about how it would feel like to draw a square using a compass.
Using a Bluetooth connection, the device transmits shapes from an electronic device such as a computer or iPhone to be drawn on paper, giving it the same precision as drawings produced using CAD software.
A 3D-printed ABS resin was used to make the prototype device. It contains a rotary encoder to detect the rotation angle, a servomotor to regulate the radius of a pen, LEDs, a switch and a micro controller.
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