It uses three high-resolution cameras to peer down at the ground below. Lit by synchronized strobe lights, an onboard computer creates a digital image of each seedling as it glides by, comparing them with all the greenery it might reasonably find in a field of rich Salinas valley farmland two hours south of San Francisco. "It puts a dot on the stem and maps around it," says Todd Rinkenberger of FarmWise, the robot's maker. "Now it knows what's plant. Everything else is a weed."

Construction is one of the most challenging sectors for artificial intelligence and robotics. When it comes to manual skills and holistic thinking, no advanced technology can hold a candle to human labor. So far, we have seen a robot putting up a wall, the various uses of augmented and virtual reality (AR/VR) and AI systems performing repetitive tasks in the construction industry that people no longer want to do. While the concepts of work and tasks for people have changed with Industry 4.0, by 2050, it is estimated that two-thirds of the world's population will live in cities, which means new cities, more housing and more roads. To meet this demand, the construction sector needs to build around 13,000 homes every day worldwide.