Hardware Reference
In-Depth Information
THIS PROJECT IS
deinitely the hardest in the whole book. It will push your mechanical and
electronic building skills possibly to the limit. It will also open up a whole new way of getting
data to your Raspberry Pi. It is a unique project, at least in the way it has been realised, and best
of all - it provokes the reaction “what the . . .” from people seeing it for the irst time.
he idea of a harmonograph is not new. It is a mechanical device that started to appear in the
mid-nineteenth century and was at the peak of its popularity in the 1890s. It is a mechanical
arrangement of pendulums that is used to create complex and detailed patterns by directly
drawing them on paper. hese things are big, and can be huge, but by using the power of the
Raspberry Pi you can make one of a modest size. An example of a pattern produced by this
project is shown in Figure 16-1.
Figure 16-1:
A harmonograph
pattern from the
Pendulum Pi.
