Short answers, pulled from the story.
The Greek astronomer Hipparchus credited Eratosthenes as the inventor of the armillary sphere between 276 BC and 194 BC. Chinese astronomers Shi Shen and Gan De developed primitive single-ring armillary instruments during the 4th century BC.
An armillary sphere consists of a brass framework of graduated rings that represent lines of celestial longitude and latitude. The equinoctial ring divides into 360 degrees to show the sun's right ascension in time while the ecliptic ring divides into 12 signs to mark the months and days of the year.
Astronomer Geng Shouchang introduced the first permanently fixed equatorial ring in 52 BC during the Western Han dynasty. Zhang Heng completed the world's first water-powered celestial globe in 125 AD using an inflow clepsydra clock to operate his armillary sphere.
In the end of the 15th century it became the personal heraldic badge of the future King Manuel I of Portugal. During his reign the intense use of this badge transformed the sphere from a simple personal symbol into a national one representing the Kingdom of Portugal and its Overseas Empire.
An artwork-based model of an Armillary sphere has been used since the 1st of March 2014 to light the Paralympic heritage flame at Stoke Mandeville Stadium. Artist Jon Bausor created this sphere which includes a wheelchair that users can rotate to spark the flame.