Swarm of tiny drones (IMAGE) Delft University of Technology Caption A swarm of tiny drones entering a building in search of a gas leak. The research team used modified "CrazyFlie" drones, which are 12 cm in diameter weighed only 37.5 grams. Credit Mavlab/TU Delft Usage Restrictions The image may only be used with appropriate caption or credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.