A construction-site security camera on a remote mountainside captured a frightening malfunction involving an autonomous concrete mixer truck, raising new concerns about heavy robotic equipment on rugged terrain. The footage shows the driverless mixer navigating a narrow dirt access road surrounded by rebar stacks and large machinery. As it nears a bend, the vehicle suddenly drifts sideways, clipping a worker who turns only a moment before being struck and knocked into the metal racks. The truck