WTF?! There isn't much the Raspberry Pi can't do. The homebrew microcomputer has been used to power devices like ventilators, a tiny TV, an exoskeleton, a mind-reading device, portable game consoles, and much more. Why not also what is perhaps the world's largest dot matrix printer?
When Ryder Damen saw workers painting the street near his house a few years ago, he wondered if he could build a machine to paint words on the road. He did just that with a specially coded Raspberry Pi and a lot of ingenuity.
The prolific tinkerer recently posted a video detailing the development process of his programmable road printer. Bolted onto the back of a truck, the device utilizes the popular microcomputer and a series of precisely-placed tubes to spray water onto the ground to make out letters.
Following the principles of a dot matrix printer, only scaled up, Damen's machine tells the tubes when to open and close to form different letters as the truck moves. The Raspberry hosts a web server where users can enter text for the machine to print.
Maintaining pressure in the tubes, wiring the tubes to the Raspberry, and routing power to the Raspberry took a lot of trial and error. However, Damen could eventually use the truck to write short messages, such as greetings.
Theoretically, the printer could deliver brief messages to anyone looking down with a drone, from an aircraft, or the upper floor of a building. It's unclear when or if Damen intends to release the source code he wrote for the Raspberry so others could potentially make road printers.
This is the first video Damen has posted on his YouTube channel in a while, but he is fond of using Raspberries to program nonsensical devices. Last year, he used the computer and some pneumonic tubes to turn a table into a miniature roller coaster that rapidly moves up and down. After a package was stolen from his doorstep, he built a deterrent using a Raspberry and artificial intelligence that sprays thieves with flour upon identifying them.
Other tinkerers have also built odd devices around Raspberries. The Beepberry is a recently unveiled Raspberry-powered attempt to resurrect the Blackberry. A "Magic" storybook contains a Raspberry which uses ChatGPT to make up fairy tales when readers open it.