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Dialog: Cam Coordinate-Data

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Cam-Coordinates Data dialog-box

Use the Cam-Coordinates dialog-box to calculate and to save the cam-coordinates in different formats.

STEP 1:

Add a 2D-Cam to the model

STEP 2:

Add a Cam-Data FB to the graphic-area.

STEP 3:

Edit the Cam-Data FB to open the Cam-Coordinates dialog-box

When the Cam-Coordinates dialog-box is open:

STEP 4:

Select a 2D-Cam

The 2D-Cam becomes linked to the Cam-Coordinates dialog-box and the Cam-Data FB

Jump to Step 7 or continue...STEP 5

STEP 5:

Calculate the Cam-Coordinates as Biarcs or as Points.

STEP 6:

Save and export the Cam-Coordinates as different file-types.

When you finish:

STEP 7:

Close the Cam-Coordinates dialog-box

STEP 8:

Use the data at the output-connectors from the Cam-Data FB for further Cam-Analysis.

		Error-Driven data :	Machine Angle
SAVE OUTPUT AS :		Bi-Arcs	Equal Increments :
STEP :		N/A	Input, Output, 'Negative Space of Follower Track'
TEXT :		Inner, Outer	Inner, Outer, Pitch-Curve
DXF :		Inner, Outer	Inner, Outer

Direct connection to SOLIDWORKS as :	Biarcs	Inner, Outer	N/A
Direct connection to SOLIDWORKS as :	'Curves'	N/A	Inner, Outer, Pitch-Curve
Table of 2D-Cam file-types

Summary of 2D-Cam 'Elements and Dialog-Boxes'

2D-Cams are modelled and analysed with different elements and FBs with dialog-boxes. Their relationships are indicated in the table below.

To obtain a 2D-Cam's kinematic-data [cam-coordinates, pressure angle, radius of curvature], you only need to link the 2D-Cam to the Cam-Data FB.

To obtain a 2D-Cam's force, stress and cam-torque data, you must also Configure the Power Source', enter the Cam's and Cam-Followers material properties, and edit the mass properties of each Part in the model.

STEP 1A

Add 2D-Cam

Select a:

➔	Part: the Cam-Part

➔	Profile: the Cam-Follower

... optional ...

STEP 1B

Open: Cam Display and Properties dialog-box

•	Display Cam1, Pitch-Circle, Cam2

•	Display Cam as Profile, Pressure Angle, Contact-Force*, Contact-Shear Stress ...

•	Enter Cam and Cam-Follower fundamental material properties [E, µ]

•	Display Colour and Line Thickness.

STEP 2A

Add Cam-Data FB

STEP 2B

Edit Cam-Data FB to open Cam-Coordinates dialog-box

Select the 2D-Cam:

Do STEP 3B immediately, or

Close Cam-Coordinates dialog-box, Do Step 3A, then do STEP 2B and STEP 3B again.

STEP 3A

Cam-Analysis [with Graph FB]

Output-Connectors of Cam-Data FB:

➔	Contact-Force*

➔	Contact-Shear-Stress*

➔	Radius-of-Curvature

➔	Pressure-Angle

➔	Entrainment Velocity [MD14+]

STEP 3B

Calculate Cam-Coordinates as Points or Arcs

➔	Save as DXF, TXT, STEP

➔	Transfer cams directly to SOLIDWORKS as

➔	Points. These are in a 'Curve' feature, which become a Spline feature in a sketch

➔	Biarcs. Arcs are transferred directly, and become are sketch elements

*Force analysis only: Configure Power Source, Mass Properties of Parts

Cam-Coordinates dialog-box

Dialog-CamCoordinates2

Cam Coordinates dialog-box - MD14.

Open the dialog, and select a cam. The 'Selected Cam-Track' shows in the box at the top of the dialog.

Clear Data in the table.

Save As: data in the table as:

STEP

DXF

ASC

TXT

Copy Data in table to Clipboard.

Toggle: Cam 1, Cam 2, or Pitch-Curve: [Cam 1 is Internal or External, Cam 2 is External or Internal].

Cam 1

Cam 2

Pitch-Curve

Click the icon to toggle between two calculation options:

Equal Increments: Calculate Cam-Coordinates with equal increments of Master Machine Angle with the 'Number-of-Points' as entered in '# Points' [10].

Chord Error: Calculate Cam with Biarcs, with a maximum Chord Error equal to the value in Box [10]

Calculate Cam Coordinates as:

XY-Points [as Equal Machine Angle Increments

Bi-Arcs [with a Chord Error]

Send Cam-Coordinates to SOLIDWORKS®.

To a new or an existing open SOLIDWORKS® Part document.

Save the active SOLIDWORKS® document before you click button

Bi-Arcs are constructed in SOLIDWORKS as a sketch entities.

Points are constructed in SOLIDWORKS as Curves, which you can convert to a Spline sketch-element. See Note 4

Note: You can also save the Cam as a STEP file.

Traffic-Light Red - Click to calculate coordinates.

Traffic Light Green - Cam Coordinates are ready. You can save them to disk or export to SOLIDWORKS®

When you click this icon, MechDesigner recalculates the Cam-Coordinates with:

•	[4]: Cam 1 or Cam 2 or the Pitch Circle Coordinates

•	[5] Equal increments of the Master Machine Angle[Points only] or Chord Error [Biarcs only]

•	[6] Points or Biarcs

[Does not do anything [MD14+]]: Closed Cam: When you calculate the Cam-Coordinates, the first and last cam point become different.

[Does do anything [MD14+]] Open Cam: The first and last coordinate become the same. The cam will be closed.

Click to display a Cam 'plot' of actual cam-points that are calculated.

Enter Maximum Chord Error

Use with 'Chord Error' option. [Minimum ~0.1µm. Experiment!]

Enter Number-of-Points

Use with 'Equal Increments' option. [Maximum ~100,000. Experiment!]

MD14+ 'Save Options' button [See 'Save Options' box, below]

Delimiter for a Cam Save as TXT file: Comma [,]; Tab [ ]; Colon [:]; Space [ ]; Semi-Colon [;]; Dash [-].

STEP File Options:

Spline with End Corrections?

Spline to Interpolate 'actual' Kinematic Points?

The Calculated Cam Coordinates, using the button settings detailed above.

'Save Options' box.

Notes:

Note 1: When you use Part Coordinate for a rotating 2D-Cam (a standard 2D-Cam), make sure the Origin of the Part is the Centre of the Cam.

Note 3: The maximum error between the 'true' cam and the actual cam data is less with Chord Error with Arcs than with Chord Error with Line.

Note 4: The data will be on the XY Plane, with Z columns as '0'. SOLIDWORKS fits a Spline to it immediately.

If you need to put the data on a different plane in SolidWorks, then you will need to change the data slightly in Excel. Add a column of zeros in the X, Y or Z column. Possibly multiply a column -1. Then import the data as a Curve entity into SOLIDWORKS.

The Cam as Arc Data has six columns:

1	2	3	4	5	6
Arc Radius	Arc Start Point X Coordinate	Arc End Point X Coordinate	Arc Start Point Y Coordinate	Arc End Point Y Coordinate	Arc Angle Range (degs)

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd