Sidhant Gupta’s invention, Clearbot, is a self-navigating, AI-powered robot that collects rubbish thrown into seas, rivers and lakes—up to a ton of it a day—sorts it and brings it to shore for recycling. Clients include Sino Group, the Hong Kong government’s Highways Department and WeRobotics. He previously founded a company that built the world’s fastest robotic fish; and made an AI-powered underwater camera for scientific research.