East Liberty, Ohio -- One recent morning, the Honda Motor Co. plant here churned out 120 Civic compacts. Then the production line came to a halt and workers in white uniforms swept in to install new hand-like parts on the giant gray robots that weld steel into the cars' frames.

About five minutes later, the line roared back to life, and the robots began zapping together a longer, taller vehicle, the CR-V crossover.

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