Last year, YouTuber Ivan Miranda built a very impressive sand drawing robot. It 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. The only problem is that it’s very large, and so now Miranda has redesigned the robot to be more compact.
The motivation behind the revision was that Miranda wanted to be able to travel with the sand drawing robot, so it needs to be able to fit into a suitcase. He still wanted it to capable of drawing large pictures, so his new design is built into sections and can be collapsed for storage and travel. That was accomplished by splitting the main axis support beam into two pieces. Once he’s ready to use it, those two pieces can be connected with internal threaded rods.
The rest of the design is pretty similar to Miranda’s original sand drawing robot. The pair of wheels at each end of the main axis are 3D-printed, and the carriage is as well. The carriage is a box design that surrounds the main beam, and rides on standard skate bearings. That’s pulled back and forth with a belt by a large stepper motor. The whole thing is powered by LiPo batteries, so Miranda can simply charge it up and take it to the beach to start drawing pictures in the sand.