They used machinery that represented continuous numeric quantities, like the angle of a shaft rotation or difference in electrical potential .
These jets contain significant kinetic energy, which is converted into shaft rotation by the bucket-like shaped rotor blades, as the steam jet changes direction.
The shaft rotation was geared up from that of the wheel which led to less power loss.
All stations feature self-lubricating bronze bushings with biomechanically accurate pivot points for friction-free shaft rotation.
Since the number of shaft rotations represented speed a cam switch was used to initiate missile control sequences such as engine throttle down and shut off.
The problem with taper keys is that they can cause the center of the shaft rotation to be slightly off of the mating part.
When a percentage is referenced, with a non-linear taper, it relates to the resistance value at the midpoint of the shaft rotation.
For example, the shaft rotation might represent an angle, and the voltage division ratio can be made proportional to the cosine of the angle.
Arbitrary functions of one variable were provided by cams, with gearing to convert follower movement to shaft rotation.
Stepper Motors - The stepper motor is an electromagnetic device that converts digital pulses into mechanical shaft rotation.