Programmable Plotting Automaton

[majorna]

I recently stumbled upon this genius contraption, which uses a combination of normal chain sections and treads to program a simple hand-cranked plotter:

It reminded me of Sariel's mechanically programmable drummer, featured on this forum less than a month ago.

It occurs to me that one might use a combination of tiles and "cheese wedge" pieces to similar effect. Can we come up with other solutions for mechanically programming our Lego creations?

[Sariel]

That sure looks way more precise than my drummer.

[roamingstop]

I remember a solution like this in one of the very early technic ideas books, with 1x4 gear racks mounted onto a technic treads...

[majorna]

Here's the plotter from the 8888 Idea Book:

As you can see, not nearly as evolved, though repeating the program by placing the rack gears on the treads is clever. I messed around with this arrangement a while back, and the rack gears stayed put on those single studs about as well as you'd expect.

I posted my own modest experiment with rack gear programming a couple months ago in another thread, but here it is again, using one of the pull-back motors for power.

Edited January 24, 2014 by majorna