YED TEPE UNIVERSITY DEPARTMENT OF MECHANICAL ENGINEERING
YEDITEPE UNIVERSITY ENGINEERING FACULTY
MECHANICAL ENGINEERING LABORATORY
Servo Motor System
1. Objective:
Introduce the students to control the speed of a servo motor system.
To test the motor in the directions of rotation with the functions of the speed control.
To conduct a reference move on a servo system.
2. Equipment:
Festo Equipment Set TP 801: Basics of servo motor drive technology, including Roller
Guide, Brushless Servo Motor, Smart Electromotor Controller, Limit switches.
24 V Power Supply
3. Theory:
A servo mechanism or servo is an automatic device that uses error sensing feedback to correct the performance of a mechanism. The term correctly applies only to systems where the feedback or error correction signals help control mechanical position or other parameters. For example, an automotive power window control is not a servomechanism, as there is no automatic feedback which controls position the operator does this by observation. By contrast the car's cruise control uses closed loop feedback, which classifies it as a servomechanism.
A servomechanism is unique from other control systems because it controls a parameter by commanding the time based derivative of that parameter. For example a servomechanism controlling position must be capable of changing the velocity of the system because the time-based derivative (rate change) of position is velocity. A hydraulic actuator controlled by a spool valve and a position sensor is a good example because the velocity of the actuator is proportional to the error signal of the position sensor.
A common type of servo provides position control. Servos are commonly electrical or partially electronic in nature, using an electric motor as the primary means of creating mechanical force. Other types of servos use hydraulics, pneumatics, or magnetic principles.
Usually, servos operate on the principle of