WOLFRAM SYSTEM MODELER

JoystickForceResponse

Model simulating response of three joystick designs to circularly varying test force.

Diagram

Wolfram Language

In[1]:=
SystemModel["EducationExamples.MechanicalEngineering.Joystick.JoystickForceResponse"]
Out[1]:=

Information

 

Joystick Design: Force Response

 

Introduction

This model compares the response of three analog joysticks to a circularly varying test force. Each joystick has a handle re-centering mechanism based on a symmetrical arrangement of a different number of tension springs.

View the model diagram for this model.

The other model in this example is JoystickReturnTrajectory, which compares the free return trajectory of the three joysticks.

 

Hierarchical Modeling

The joystick model is constructed hierarchically. Double-click on a component such as fourSpringReturn1 to see its model diagram. Inside fourSpringReturn1 double-click on one of the tension springs to see its model diagram, and so on:

hierarchical

 

Simulation & Animation

To simulate the model and view a 3D animation of it, follow the steps below:

  • Click the simCenter button in the top-right corner.
  • When the build is finished, click the Simulate button simulate.
  • Click the Animate button animate.
  • Use your mouse or trackpad to drag the animation into a good angle, and zoom in with your scroll wheel or by using the trackpad. Then click the play button to play the animation.

The animation shows the response of the joystick handles to a test force that attempts to trace out a circle:

animation

Note that the response of the joysticks is not perfectly circular. The joysticks with a larger number of symmetrically spaced springs (four or six) trace out a path that is more nearly circular.

 

Visualization

After simulating the model, look at the stored plots to see the path traced out by the joysticks.

parametricPlotsForceResponse

You can see that the six-spring arrangement leads to the most circular force response.

By simulating the other model in this example, JoystickReturnTrajectory, you can also obtain the following parametric plots of the trajectory of each joystick as it re-centers itself after being displaced:

parametricPlotsReturnTrajectory

You can see that the six-spring arrangement leads to the most linear return trajectory.

 

Parameters (2)

appliedForce

Value: 0.1

Type: Force (N)

Description: Force applied on the joysticks.

springConstants

Value: 100

Type: TranslationalSpringConstant (N/m)

Description: Base spring constant of the joystick springs.

Components (26)

world

Type: World

joystickJoint1

Type: JoystickJoint

bodyCylinder1

Type: BodyCylinder

bodyCylinder2

Type: BodyCylinder

rotatingRadialForce2

Type: RotatingRadialForce

threeSpringReturn1

Type: ThreeSpringReturn

fixedTranslation1

Type: FixedTranslation

fixedTranslation2

Type: FixedTranslation

fourSpringReturn1

Type: FourSpringReturn

rotatingRadialForce3

Type: RotatingRadialForce

bodyCylinder3

Type: BodyCylinder

bodyCylinder4

Type: BodyCylinder

joystickJoint2

Type: JoystickJoint

fixedTranslation3

Type: FixedTranslation

joystickJoint3

Type: JoystickJoint

bodyCylinder5

Type: BodyCylinder

bodyCylinder6

Type: BodyCylinder

rotatingRadialForce4

Type: RotatingRadialForce

sixSpringReturn1

Type: SixSpringReturn

fixedTranslation4

Type: FixedTranslation

fixedTranslation5

Type: FixedTranslation

fixedShape21

Type: FixedShape2

fixed1

Type: Fixed

fixedTranslation6

Type: FixedTranslation

fixedTranslation7

Type: FixedTranslation

fixedTranslation8

Type: FixedTranslation