How robots could save one of the world's most unusual cathedrals

Under construction for 138 years and counting, the Sagrada Família is one of the most complex buildings ever conceived. Will robotic tools finally help finish it?

How robots could save one of the world's most unusual cathedrals
Under construction for 138 years and counting, the Sagrada Família is one of the most complex buildings ever conceived. Will robotic tools finally help finish it?