WOLFRAM SYSTEM MODELER

WeakServoMechanism

A servo mechanism with a weak axis

Diagram

Wolfram Language

In[1]:=
SystemModel["IntroductoryExamples.MultiDomain.WeakServoMechanism"]
Out[1]:=

Information

The structure of the control system is shown in the schematic picture below. It consists of an input signal, a sensor, a feedback loop, and a regulator. The physical system consists of the gear and axis system described in DC Motor and Weak Axis. Since the physical system has negative static gain the PI gain also has to be negative.

In the stiff servo mechanism example it is shown how different controller gains affect the response. After selecting a gain k = 1.5 for both the stiff and weak axis systems we can compare the results:

As seen the controller design made using the stiff axis model performs well also when the more accurate weak axis is used in simulations.

For a step by step tutorial see Multidomain—A Servo Mechanism.

Components (14)

ground1

Type: Ground

Description: Ground node

inertia1

Type: Inertia

Description: 1D-rotational component with inertia

idealGear1

Type: IdealGear

Description: Ideal gear without inertia

EMF1

Type: RotationalEMF

Description: Electromotoric force (electric/mechanic transformer)

signalVoltage1

Type: SignalVoltage

Description: Generic voltage source using the input signal as source voltage

feedback1

Type: Feedback

Description: Output difference between commanded and feedback input

step1

Type: Step

Description: Generate step signal of type Real

resistor1

Type: Resistor

Description: Ideal linear electrical resistor

inductor1

Type: Inductor

Description: Ideal linear electrical inductor

speedSensor1

Type: SpeedSensor

Description: Ideal sensor to measure the absolute flange angular velocity

inertia2

Type: Inertia

Description: 1D-rotational component with inertia

spring1

Type: Spring

Description: Linear 1D rotational spring

inertia3

Type: Inertia

Description: 1D-rotational component with inertia

PI1

Type: PI

Description: Proportional-Integral controller