Many people love the Raspberry Pi (including us). The computer cards are not only cheap, you can also do so much with them. Wild, wonderful projects are popping up all the time with RPi boards as a central part. The latest creation that caught our attention is perhaps one of the most astonishing: a pickup truck turned into a dot matrix printer.
YouTuber Ryder Damen (who runs the channel Ryder Calm Down) uses a Raspberry Pi to control his home-built “printer”, which involves a pickup truck, water and a whole set of tools to print messages on the ground. He calls it “skywriting, but on the road”.
In the video, Ryder explains how the idea came about (he saw trucks painting markers on the road), as well as how he constructed the “printer” and what materials were used. A sheet of plywood and a towbar make up the rig’s frame, and solenoids, valves, and hoses are then attached to the wood to act as printer parts. The solenoids control the valves – when 12V power is applied, they open. At the same time, the hoses divide the water flow from a central point (a pump and a bucket full of water) to each valve.
The set is controlled by the Raspberry Pi, which is connected to each valve via a relay and the solenoids. Ryder Damen has created a website for the device, where you can type in the message you want and choose how quickly the printing will take place. He comments in the video that you can also choose a font, but “only one font works”. The message is then converted into an image, analyzed and divided into segments based on the number of valves on the truck. The code determines whether each valve is in an area considered light or dark: If it is dark, the valve sprays water. If it is bright, the valve stops.
Ryder Damen / YouTube
As part of the video, Ryder shares some of the ups and downs of the project, including all the troubleshooting that was required at each step of the process. When it looked like the Raspberry Pi would have died from the first relay used, I actually heaved a sigh of sympathy – as Damen notes, the Raspberry Pi has been hard to come by and replacing it would be difficult. It’s a fun journey to follow, especially if you’ve ever used a dot matrix printer.
If you happen to want to build your own road-writing truck, the code for the project is now available on Github – and the Raspberry Pi Foundation says that supply will soon increase, finally making it possible to get your hands on one again. But if that’s not your thing, Damen’s videos about other projects might entertain you instead. As Tom’s Hardware explains in its article about the matrix car, you can also watch pirates on the porch get their punishment or build your own Christmas lights from Stranger Things.