If you thought elaborate sand castles were the only way one could express their artistic vision on the beach, Disney Research and ETH Zürich want to introduce you to their Beachbot. Slightly larger than a Roomba, the cartoonish robot turtle uses innovative soft balloon-like wheels so that it doesn't leave a trail while rolling across a beach, but can deploy a built-in rake as needed to draw elaborate designs in the sand.
Beachbot can be controlled remotely allowing an operator to use it to draw directly on a beach, but it can also be programmed with a pre-loaded design or image. In that case, four white poles are placed in the sand to establish the size of the giant canvas, which the Beachbot then uses to keep track of its position -- with a high degree of accuracy -- as it autonomously reproduces a design.
Practical applications of the technology seem limited to companies creating giant advertisements on a crowded beach, but resorts could use the Beachbot to designate private sections of their waterfront property, letting guests reserve a premiere spot to soak up the sun. And were you and the Beachbot (and a laptop) the only survivors of a shipwreck that washed ashore, it would certainly be a useful tool for spelling out SOS and rescue messages.