Over past years, drones evolved from an underdeveloped dream to highly advanced tool that is widely available. As a result, many companies thought of different ways to implement drones to their businesses. The new idea brought by Amazon or UPS is being able to deliver goods using drone technology. Undoubtedly, this project seems to be a huge step forward of delivery service. Nonetheless, Nirupam Roy and Nakul Garg, a pair of engineers at the University of Maryland, are afraid that drone deliveries will be frequent target of vandalism. As we know, a well-aimed stone or tennis ball can easily take a drone down. Therefore, the men decided to build a lightweight self-defence mechanism which lets a drone get out of the way of missile.
Dr Roy and Mr Garg think that they can replace power-hungry radar antennae or spinning lidar units by harnesses sound waves and the Doppler effect. The pair plan to equip drones with diminutive loudspeakers which would broadcast an ultrasonic tone outward from the drone. Also, those tiny microphones would listen for reflection for incoming objects. All those actions would give a chance to recognise the incoming threat and thus permit the drone to get out of its way.
Dr Roy and Mr Garg called their new invention DopplerDodge drone defence system. To test it, they have been throwing objects of various sizes at it and found out that system detects objects from distances of up to four metres away. However, the two researchers will attempt to raise the detection range to 30 meters, what will make drones impossible to hit by any irritated neighbour.
Sources:
https://www.economist.com/science-and-technology/2020/02/27/as-delivery-drones-multiply-they-may-need-to-protect-themselves