The rover was more of a camel, with a knobby-kneed chassis and a long, many-jointed neck, surmounted by a binocular head.

NEWYORKER: The Martian Chroniclers

"As the hammerhead head has expanded, the degree of binocular overlap has increased with it, " Dr McComb explains.

BBC: Earth News - Hammerhead shark mystery solved

But creating a binocular stereo image requires precise adjustments based on different head sizes and asymmetries as well as continuously aligning two images while compensating for head movement.

FORBES: Google Glass V2 Could Be Binocular, And Even Double As Stealth Hearing Aids