The Bidirectional Stepper Motor project described here takes the principles of a current-pulse operated watch hand movement, and enables operation in both clockwise and anticlockwise directions. The system is built around microcontroller AVR ATtiny13.
“This design was used to provide the altitude indication for a skydiver’s altimeter. The altitude indication for such an instrument must be, above all, clear and easily read, and for this reason, a mechanical pointer is considered the best type of indicator, rather than an LCD display. The pointer mechanism must also be able to move equally well in both clockwise and anticlockwise directions to show altitude on the way up as well as on the way down”, said Chris Belcher, the project designer.