SearchWing is a German nonprofit organisation which builds and flies drones for maritime search and rescue (SAR). The drones are sent out to find and rescue people in distress on the open sea. Most often, SearchWing helps refugees trying to reach Europe in unsafe vessels.
The drones are built on Raspberry Pi hardware and software. Compute Module 4 is the brains, and dual Raspberry Pi Camera Modules are the eyes of each drone. AI-based boat detection software does the seeking and sends location information back to the rescue ship so it knows where to go to pick up the stranded people.
Flight paths are pre-planned on a tablet and parsed on board by the Raspberry Pi. Each flight lasts 60 minutes and the drones have an operating altitude of 300-500 metres. Cruising speed is 50km per hour, and they’re capable of scanning a 184km2. Constant contact with the base station is maintained and the drones have a 100km range.
The drones are 102cm x 59cm x 59cm and weigh 2kg. They cost around €1000 to build. They are designed to be launched like a paper plane. You just throw them out into the air and they take flight.
Research has already been undertaken to explore how the drones’ search area can be expanded by fiddling with the angle of the cameras to achieve a wider ‘sweep width’. The research paper initially compared the efficiency of planes, drones and other vessels in maritime search and rescue.
Julian from SearchWing got in touch to tell us how Raspberry Pi is helping with their work. He explained the “long and painful” process trying to make sure the electronics in the drone were waterproof. They tried many different 3D prints of a box of their own design but settled with proper waterproof IP68 connectors and an SLA printed box.
The design and building of the custom board inside each drone ended up as the Bachelors thesis for a SearchWing team member.
Working together to rescue stranded people
This mission report from last December features SearchWing’s Philipp Borgers talking about testing the current version of the drone under real conditions on the Canary Islands in the Atlantic. SearchWing works alongside other rescue agencies to make quicker work of searching large areas of water, leaving the rescue boats time to do more rescuing and less searching. The Canary Islands mission was a joint effort between SearchWing and Mission Lifeline.