Ivan Miranda Modifies His Sand Drawing Robot to Be More Portable

The robot had motorized wheels at either end of a long axis and linear rail, and could drive along the beach. As it did, a carriage would move back and forth across that axis. A servo arm on the carriage could be lowered to dig into the sand, and ultimately draw pictures.

Source: blog.hackster.io/ivan-miranda-modifies-his-sand-drawing-robot-to-be-more-portable-91d621b39c72