Which device provides precise angular position feedback by encoding rotational movement?

Which device provides precise angular position feedback by encoding rotational movement?

• A. Potentiometer
• B. Linear encoder
• C. Rotary encoder
• D. Proximity sensor

Answer: (C)

Precise angular position feedback relies on a device that turns rotation into an encoded electrical signal the control system can read. A rotary encoder does this by attaching to the shaft and converting each small turn into a sequence of signals that map to an angle. Incremental encoders provide pulses as the shaft moves, allowing the controller to track relative position and speed by counting the pulses and decoding their phase. Absolute encoders, on the other hand, output a unique code for each angle, so the exact position is known even after power is removed. These encoders can be optical (using light through a patterned disk) or magnetic (using changes in magnetic fields), offering high resolution and fast response for servo and CNC applications. In contrast, a potentiometer gives an analog position with a single variable resistance and wears with use; a linear encoder measures linear, not rotational, displacement; and a proximity sensor detects the presence of a nearby object rather than position.

Precise angular position feedback relies on a device that turns rotation into an encoded electrical signal the control system can read. A rotary encoder does this by attaching to the shaft and converting each small turn into a sequence of signals that map to an angle. Incremental encoders provide pulses as the shaft moves, allowing the controller to track relative position and speed by counting the pulses and decoding their phase. Absolute encoders, on the other hand, output a unique code for each angle, so the exact position is known even after power is removed. These encoders can be optical (using light through a patterned disk) or magnetic (using changes in magnetic fields), offering high resolution and fast response for servo and CNC applications. In contrast, a potentiometer gives an analog position with a single variable resistance and wears with use; a linear encoder measures linear, not rotational, displacement; and a proximity sensor detects the presence of a nearby object rather than position.