Step 1.6: Rotate the Part - CW & CCW

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Step 1.6: Rotate the Part - CW & CCW

Objective of this Step:

•To understand the basics of how to use Function-Blocks.

•To connect wires between different Function-Blocks.

•Delete wires between Function-Blocks.

•To move a Part with Constant Angular Velocity - or Uniform Rotary Motion.

See also: How to Connect Function-Blocks

Terminology:

Term :

Definition

Motion-Part :

A Part whose position relative to a different Part you control with a Motion-Dimension FB.

Rocker :

A Motion-Part that rotates with a non-uniform rotary motion.

Crank :

A Rocker that rotates with a uniform angular velocity.

a Part that is kinematically-defined :

A part whose state is solved. It has a Mobility of zero. You can plot its position, velocity, and acceleration motion-values.

FB :

Abbreviation for Function-Block.

Connect a wire :

Drag a wire from the output-connector of one Function-Block to the input-connector of a different Function-Block.

Motion-Values :

Displacement, velocity, and acceleration data that flows through Function-Blocks and along wires that connect Function-Blocks.

Video

STEP 1.6: Rotate the Part

Schematic 'wiring-diagram' of Kinematic Function-Blocks

Schematic of Function-Blocks

•Use Kinematic Function-Blocks to transfer motion-values to Motion-Parts and Motion-Points

•Connect wires from output-connectors of Function-Blocks to the input-connectors of different Function-Block.

The schematic diagram, to the left, attempts to show how you can connect wires between different types of Function-Blocks.

Motion-Providers: have output-connectors. The motion-values are either equal to the MMA or the motion is from the motion measurement of a Part or Point in a kinematically-defined chain.

Motion-Processor: use the motion-values from Motion-Providers as the independent variable for their internal function. You can actively design their functions.

Motion-Part: identified by a Motion-Dimension FB. Control its motion with motion-values at the input-connector to the Motion-Dimension FB.

Motion-Point: identified by a Motion-Path FB. Control its motion with motion-values at the input-connector to the Motion-Path FB.

Tutorial Steps:

Add a Linear Motion FB; Connect a wire to the Motion Dimension FB

Toolbar-Kinematics-FB-small-short-LinearMotionFB

STEP 1: Select the Linear-Motion FB.

The Kinematic-FB toolbar is to the right of the graphics-area.

1.Click the Kinematic-FB toolbar > Linear-Motion FB

 
 

GST-1-601-LinearMotionFB

STEP 2: Click in the graphics-area.

1.Click the graphics-area to the left of the Motion-Dimension FBRed-14-2

The Linear-Motion FBRed-14-1b is now in the graphics-area.

 

 

STEP 3: Connect Function-Blocks with wires.

1.Drag a wire from the output-connectorRed-14-3 of the Linear-Motion FB ...

... to the input-connectorRed-14-4 of the Motion-Dimension FB

or

See how to Connect Function-Blocks

STEP 4: Cycle the kinematic-chain.

1.Click Run toolbar > Cycle icon

or

1.Click Run menu > Cycle

or

1.Press the ALT+C key combination on your keyboard to start and stop the cycle command.

GST-1-602-LMFBtoMDFB

GST-Icon-Run-Cycle

Summary:

Because we control the position / motion of a Part with a Motion-Dimension, we call the Part a Motion-Part.

Because the Part is a rotating-Part, we call it a Rocker.

Because the output from the Linear-Motion FB increases at a constant rate, the Rocker also rotates in the counter-clockwise direction with a uniform angular velocity.

Because the Rocker rotates with a uniform angular velocity, we call it a Crank.

Because the output from the Linear-Motion FB increases from 0 to 360 in one machine-cycle, the Crank rotates one time with each Machine-Cycle.

Watch the pointer under the Master Machine Angle move from 0 to 360 each time the Part rotates one time.

Rotate the Part in a Clockwise direction

When we increase the angle of a Motion-Dimension, we rotate a Motion-Part in the counter-clockwise direction.

Because the motion-values at the output from the Linear-Motion FB always increase, the Crank also rotates in the counter-clockwise direction (the direction of increasing angles).

Toolbar-Kinematics-FB-small-short-GearingFB

To rotate the Crank in a negative or clockwise direction:

STEP 1: Add a Gearing FB

1.Click Kinematic-FB toolbar > Add Gearing FB

2.Click in the graphics-area.

The Gearing FB is now in the graphics-area.

GST-1-603-LMFBtoGFBtoMDFB

STEP 2: Delete the wire between the Linear-Motion FB and the Motion-Dimension FB

To delete a wire:

1.Click the wire in the graphics-area

2.Click the Delete key on your keyboard

STEP 3: Connect wires between the Function-Block

1.Drag a wireRed-14-1 from the Linear-Motion FB to the Gearing FB

2.Drag a wireRed-14-2 from the Gearing FB to the Motion-Dimension FB

 

 
Gearing FB dialog > Gearing-Ratio

Gearing FB dialog > Gearing-Ratio

STEP 4: Edit the Gearing dialog

1.Double-Click the Gearing FB  

2.Edit the Ration and Gearing Ratio parameter to -1.

3.Click OK-tiny-11-15 to close the Gearing FB Dialog

STEP 5: Cycle the kinematic-chain.

1.Click Run toolbar > Cycle icon

or

1.Click Run menu > Cycle

or

1.Press the ALT+C keys on your keyboard to start and stop the cycle command.

The Crank now rotates in a Clockwise direction.

Other Notes

Master Machine Angle (MMA)

Master Machine Angle Indicator

Master Machine Angle Scale in the Feedback Area

 

Revs: (read-only) a counter for each time the machine angle progressives from 0 to 360

Pointer (▲): below the MMA scale ; the approximate value of the Master Machine Angle

Machine Angle (read -write) the exact value of the Master Machine Angle

To edit the value of the Master Machine Angle

Approximately : Drag, to the left or right, with your mouse-pointer in the MMA scale.

Exactly : Edit the value in the Machine Angle box.

Animation Speed

Animation Speed Slider

Animation Speed Slider Scale in the Feedback-Area

Edit the Animation-Speed

The Animation-Speed does not change kinematic results.

•Drag to the left or right with your mouse-pointer in the Animation-Speed Slider Scale.

Edit the Simulation-Speed

The Simulation-Speed does change the kinematic results.

•Edit the simulation-speed with Edit menu (or toolbar) > Machine Settings > Cycles / Minute (RPM)