Controlling 3-D objects by sketching 2-D views

User control of robotic or graphic objects containing many internal degrees of freedom is difficult - existing input devices do not map well onto the parameters of highly articulated objects. When a high degree of precision is not required, as is often the case when driving graphics for 3-D animation, we show that the 3-D position and orientation of the object and the values of its joints can be recovered from 2-D sketches of the object. Such freehand sketches represent projections of the object onto the picture plane as the user wants to see it. The result is a very intuitive method for 'sketching in 3-D'. To test the robustness with respect to freehand drawing, a particularly 'noisy' form of sensory data, we experiment with freehand strokes that artists sketch to directly position, orient and control the joints of 3-D human-like stick figures.