MATT O'BRIEN AP Technology Writer NORTH HAVEN, Conn. (AP) — Guess who's getting used to working with robots in their everyday lives? The very same warehouse workers once predicted to be losing their jobs to mechanical replacements. But doing your job side-by-side with robots isn't easy. According to their makers, the machines should take on the most mundane and physically strenuous tasks. In reality, they're also creating new forms of stress and strain in the form of injuries and the unease of working in close quarters with mobile half-ton devices that direct themselves. "They weigh a lot," Amazon worker Amanda Taillon said during the pre-Christmas rush at a company warehouse in Connecticut. Nearby, a fleet of 6-foot-tall roving robot shelves zipped around behind a chain-link fence.