Posisjonsfeedback

Posisjonsfeedback refers to the practice in control engineering and automation of measuring the actual position of a moving component and feeding this information back to the control system. The goal is to reduce the deviation between the desired position (setpunkt) and the actual position by adjusting the actuator input in real time.

Measurements are typically made with sensors such as encoders, potentiometers, or resolvers. Absolute encoders provide a unique position value for every pose, while incremental encoders give relative position and require reference positions after startup. Common technologies include optical, magnetic, and Hall effect encoders. Resolvers offer robustness in harsh environments.

In a closed-loop control system, posisjonsfeedback is used together with a controller (often PID) to generate the command signal for the actuator. The error between the setpunkt and the measured position drives adjustments in speed and position to achieve the desired outcome. Feedback improves accuracy, repeatability, and stability against disturbances and varying loads.

Typical applications include precision machinery such as CNC machines, robotic arms, and automated production lines, as well as optical focusing and positioning tasks in imaging equipment. The main benefits are higher positioning accuracy, improved repeatability, and better resilience to external forces.

Challenges include sensor resolution and noise, mechanical backlash, thermal drift, and the need for regular calibration. The choice of sensor depends on required accuracy, environmental conditions, and cost.