With a small blue crane, four researchers hoist a cylindrical fuel cell, which looks like a stack of flattened silver and gold soda cans bundled together, into the air and lower it into a rectangular cart on wheels. A tangle of tubes and wires spirals away from the system, where nearly 270 sensors and 1,000 components are nestled inside. With a small blue crane, four researchers hoist a cylindrical fuel cell, which looks like a stack of flattened silver and gold soda cans bundled together, into the air and lower it into a rectangular cart on wheels. A tangle of tubes and wires spiral... [3374 chars]