Handwriting Robots Are Sending Snail Mail

As a kid, you might remember taking a whole fistful of markers or crayons, gently lining them all up for maximum contact, mashing them into the paper, and marveling at the colorful multitude of lines. It seemed like an easy way to write many times more things with less effort. While not quite the same idea but in a similar vein, [Aaron Francis] shared an experience of creating handwriting robots to write thousands of letters.

Why did [Aaron] need to write thousands of letters? Direct mailing, of course! If you were sending someone a letter, if it looked handwritten they’re much more likely to open it. What better way to make it look handwritten than to use a pen rather than a printer? They started off with Axidraw, a simple plotter made by EMSL. Old laptops controlled a few plotters and they started to make progress. As with most things, scale became tricky. Adding more plotters just means more paper to replace and machines to restart. An automated system of replacing paper is fiendishly difficult so they went for a batching system. A sheet of plywood that can hold dozens of sheets of paper became the basis of a new mega-plotter. 3D printers and laser cutters helped make adapters and homing teeth. A Raspberry Pi replaced the old laptops and they scaled up to a few machines.

All in all, a pretty impressive build. If you’re looking to dip your toes into the plotting water, this pen plotter is about as simple as you can get.

Plot And Visualise Brain Data In An Artwork

One of the most interesting streams through which we receive new projects to write about here at Hackaday comes from the intersection between technologists and artists. Those artists who straddle both disciplines bring creativity that those of us without their backgrounds can only dream of. The artist [Rosa Francesca] produced a piece called Cinematica, in which she monitored her brain waves with an EEG and from them produced on-paper visualizations with a pen plotter.

The hardware in use is an Interaxon Muse EEG headband read through the Muse Monitor app, and some code to drive an Evil Mad Scientist AxiDraw V3 plotter via its serial port. The write-up goes in some depth into the different types of brain waves, explaining her choice of monitoring gamma and theta waves for her source data. The result is a series of repeating shapes that vary with the brain waves of the wearer, creating drawings that are both pleasing and unique.

If you’re interested by the Muse headset used in this artwork, you might find a teardown we covered a few years ago to be of interest. And if you’re tempted by the plotter, you can always try making your own.

Thanks, @tanurai for the tip!