Inside a metal cage in a featureless room 30 miles west of Boston, Massachusetts, a marvel of modern technology whirs to life. Surrounding it, with pens, dictaphones and phone cameras poised, 100 journalists from every corner of the globe wait for their first glimpse of the future. 

Sparrow, a yellow robotic arm fitted with a many-pronged, Amazon-designed ‘hand’, suddenly stirs with a loud hiss, using its suction-cupped ‘fingers’ and advanced AI to select products from one yellow box into several, different grey ones.