10.3 A solar tracker sundial attached to the globe (Summer 1994)

First of all, forget all the pictures in the globe except the spherical co-ordinates which are used as spherical solar azimuth and solar altitude co-ordinates. I marked on transparent plastic sheets (in small segments) the solar path. I then wrapped these segments around the globe to form the complete solar path.

The blue and red segment straps are marked with finer time interval lines and the analemma, red for March-June-September, blue for September-December-March.

The hollow tube has to be adjusted to track the sunlight which will impinge via the tube onto the solar path, seen at the surface of the globe. The tube and its mount are toy parts.

If the transparent plastic straps can be easily adjusted, it can also easily perform universal sundial functions.

See A Paper by KP Cheung, illustrating that this universal sundial can also perform as a universal solar chart, and works as a universal sun-earth direction-time relationship demonstrating device.

There is also a papaer on Lightless-1 Heliodon written by KP Cheung, relating closely to this sundial.

Photos P34-P38 show the sundial prototype set for the latitude of Hong Kong.