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Dialog: Function-Block: Linear-Motion

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Linear-Motion FB

Summary of Linear-Motion FB

The default motion-values at the output of the Linear-Motion FB are equal to the Master Machine Angle.

Thus, the output continuously increases from 0 to 360, again, and again.

You can use the Linear-Motion FB to add or subtract a constant value from the MMA., so that motion-values at its output become 'before' or 'after' the Master Machine Angle.

Add and Edit Linear-Motion-FB

Toolbar:

Kinematics FB toolbar > Linear-Motion FB [Right-side of Graphic-Area]

Menu:

Add menu > Add Gearing FB

Add:

STEP 1: Add the Linear-Motion Function-Block to the graphic-area

1.	Single-Click the Linear-Motion FB in the Kinematics FB Toolbar.

2.	Single-Click again in the graphic-area to 'place' the FB in the graphic-area.

The Linear-Motion FB is now in the graphic-area.

Edit:

STEP 2: Open the Linear-Motion Function-Block dialog-box:

1.	Double-click the Linear-Motion FB in the graphic-area.

- or -

1.	See 'How to Open a Dialog-Box'.

Linear-Motion FB dialog-box

The 'Function' of the Linear-Motion FB:

Output motion-value = Master Machine Angle + Constant

Optionally, select the Accumulate option, so that the output does not reset to 0 after each machine cycle.

The 'Function' of the Linear-Motion FB is then:

Output motion-value = (Revs * 360) + Master Machine Angle + Constant

Linear Motion FB dialog-box

Linear-Motion FB dialog-box:

Machine Angle +

Enter a motion-value in the Machine Angle + 'data box'.

In the example: the motion-value = '53.4'.

Thus, if the Master-Machine-Angle is '120', the output motion-value from the Linear-Motion FB = 120 + 53.4 = 173.4

When the Machine-Angle is made to be:
'Positive', then the output is 'before' [it 'leads'], the Master Machine Angle.
'Negative', then the output is 'after' [it 'lags'], the Master Machine Angle.

Output Options:

•	Reset after one Cycle [default option and most typical] Output = Master Machine Angle + Value

- or -

•	Accumulate Output = (Revs * 360) + Master Machine Angle + Value

3.	Click the OK to close the dialog.

Notes on: 'Accumulate' or 'Reset after one Cycle' :

Generally, use Reset after one Cycle

Use 'Accumulate' when you want to model a watch, or a mechanism that does not have a motion-period equal to the Master-Machine-Angle.

Notes:

You must use a Linear-Motion FB in the 'first' kinematic-chain in the 'first' Mechanism-Editor.