The perfect balance of simplicity and complexity have been struck with this automated artist. The Roboartist is a vector drawing robot project which [Niazangels], [Maxarjun], and [Ashwin] have been documenting for the last few days. The killer feature of the build is the ability to process what is seen through a webcam so that it may be sketched as ink on paper by the robotic arm.
The arm itself has four stages, and as you can see in the video below, remarkably little slop. The remaining slight wiggle is just enough to make the images seem as if they were not printed to perfection, and we like that effect!
Above is a still of Roboartist working on a portrait of [Heath Ledger] in his role as Joker from The Dark Knight. The image import feature was used for this. It runs a tweaked version of the Canny Edge Detector to determine where the pen strokes go. This is an alternative to capturing the subject through the webcam. For now MATLAB is part of the software chain, but future work seeks to upgrade to more Open Source tools. The hardware itself uses an Arduino Mega to take input via USB or Bluetooth and drives the quartet of servo motors accordingly.
In addition to the LEDs you can see around the perimeter of the acrylic drawing surface, there are also rows of RGB strips below. The software runs a filter for the under lighting in order to compliment the lines on the paper. This is why there is a violet hue that fades out toward one side of the drawing.
Roboartist would be a fantastic office art piece; you can parade the VIPs in front of its camera as they come in for meetings and present them with a sketch as they depart!