Physical Pantograph & Software Emulator

“A pantograph is a mechanical linkage connected in a special manner based on parallelograms so that the movement of one specified point is an amplified version of the movement of another point. If a line drawing is traced by the first point, an enlarged (or miniaturized) copy will be drawn by a pen fixed to the other.” – from Wikipedia

I built a physical pantograph out of cardboard and an accompanying software emulator of the device. By using an angle sensor (or potentiometer) at any of the four joints of the parallelogram, it is possible to use the physical pantograph to control the software version. In its current implementation, the software version is controlled by mouse.

Physical Pantograph:

Physical Pantograph

Here is a screenshot of the Pantograph Software Emulator. The green line has been drawn by the stylus (mouse) point and the red line has been drawn by the pen point. This pantograph does 2X enlarging:

Pantograph Emulator

Pantograph Emulator: [Source Code] [Use Online Version]

Here is a drawing made with my physical pantograph:

Apple on table with sofa behind it.

Here is a drawing made with the software emulator:


  1. #1 by john on January 9, 2010 - 7:06 am

    I have been writing a sketch based modeling program.. and your site has me wondering do you know if it is possible to reverse project a curve (like isometric projection) knowing the angle of view relative to a plain into a 3 dimensional curve a reverse affine transformation… it possible with orthographic strait lines but can it be done with a free form curve? something tells me you need two points of reference to make it happen..

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