Engineering Excellence - Self-Propelled Car

This is one of Leonardo's most famous technical drawings because it is considered to foreshadow the modern car. It was initially designed as a stage prop for a spectacular theatrical production at the court in Milan.
The cart could be set to move either in a straight line or following a curved path. When the crossbow mechanism was released, energy was transmitted via springs to the gears linked to the wheel. The rear wheels had differential gears so that they could rotate independently.
On stage, the driverless cart would move from one side to the other without anyone pushing it.