MechDesigner Reference & User Interface > Dialogs > Dialog: Function-Block: Cam-Coordinates

Cam-Data FB > Cam-Coordinates

See Add Cam-Data FB

Use a Cam-Data FB to calculate Cam-Coordinates for the Cam-Profile.

Calculate the Inner, Outer, and/or Pitch-Center Cam-Profiles as:

•XY-Points

•BiArcs

Export a Cam-Profile directly to SolidWorks as XY-Points or BiArcs.

Save the Cam-Coordinates to your hard-drive with these file types:

•.TXT - XY-Points or BiArcs

•.CSV - XY-Points or BiArcs - see Note

•.DXF - XY-Points or BiArcs

•.SLDCRV (import to SOLIDWORKS for a “Curve through XYZ Points” feature)

•.STP : see Options for: Save Cam as a STEP file

Notes

CSV delimiter (List Separator) - see Application-Settings > Number Format tab > Data Output Format > List Separator / Delimiter Option

In the 2D-Cam dialog > Parameters tab > Cam Range and Radius separator, there are two parameters: Cam-Start and Cam-Range.

Cam-Start These edit the first Cam-Coordinateyou edit the range of the MMA over which to calculate the cam. You can also edit the start of the cam (relative to the MMA)

We calculate for you and export the Cam-Coordinates:

•from Cam-Start (default = 0) to Cam+Start + Cam-Range (default = 360)

Edit the 2D-Cam to edit Cam-Start and/or Cam Range - see 2D-Cam dialog - Parameters tab.

2D-Cam Work-flow

Action	Help Topic
Before you start this work-flow: add a kinematic-chain for the Cam-Part and a kinematic-chain for the Follower-Part; add mass-properties to the Parts; develop the motion design. The two kinematic-chains must be kinematically-defined.
1.Add a 2D-Cam; or if Conjugate Cams then 2 × Follower-Rollers and 2 × 2D-Cams; or if a Groove-Cam then two concentric (co-axial) Follower-Rollers with one for the Inner-flank only, and the one for the Outer-flank only.	see Add 2D-Cam
If the new 2D-Cam is one of two Conjugate-Cams, or it is one flank of a Groove-Cam, then:
i.Add a Conjugate-Cam FB ii.Open the Conjugate-Cam dialog and select the one flank each from two 2D-Cams	see Add Conjugate Cam FB see Conjugate-Cam dialog
2.In the Kinematics-Tree, select the 2D-Cam or a Conjugate-Cam FB as the Power Source for the kinematic-chain that includes the Follower-Part	see Configure-Power Source
3.Edit the 2D-Cam: to open the 2D-Cam dialog: review Display, Properties, Roller-Life, Cam-Life tabs	see 2D-Cam dialog
4.Add a Cam-Data FB	see Add Cam-Data FB
5.Edit the Cam-Data FB to link it to a 2D-Cam - close the dialog	see Cam-Data dialog
6.Connect wires from the output-connectors of the Cam-Data FB to a Graph FB
7.Open the Graph FB to analyze the 2D-Cam: Contact-Force, Maximum Shear-Stress, Radius-of-Curvature, Pressure-Angle, Sliding-Velocity.	see Cam-Data dialog : Cam Analysis
8.Edit the Cam-Data FB again to calculate the Cam's Coordinates	see Cam-Data dialog : Cam-Coordinates

Cam-Data dialog: Cam-Coordinates

If you see “Select a Cam to activate this form”, then click a 2D-Cam in the Assembly-Tree or graphics-area to link it to the Cam-Data FB - see Cam-Analysis

- Cam-Coordinates toolbar ( see toolbar below )

- End-Caps - shows ONLY when the first XY-coordinate of the Cam is not equal the last XY-coordinate. For example, a linear Slot-Cam.

- Inner / Outer - status of the cams after the Cam-Coordinate calculations ( see Cam Status )

- Cam Options - calculate, display, and/or save the cam-profile coordinates for the Inner, Outer, Groove, or Negative Groove cam-type. Negative Groove is for a STEP file only.

- Radial Clearance - offset the Cam-Profile from the true Cam-Profile.

- # Points - calculate as XY-Points ( see toolbar below )

- BiArc Error - calculate as BiArcs ( see toolbar below )

Click icon to switch between XY-Points and BiArcs.
		Clear ALL coordinates from the table
		Save Cam-Coordinate data as: •STP(STEP)- XY Points only •DXF •CSV •TXT •SLDCRV (SOLIDWORKS Curve file, tab delimited ) - XY Points + Z-data = 0 Note: If this icon is not enabled, make sure Plate-Radius is larger than the Maximum Radius of the Outer Cam. OR: Click Inner or Outer to recalculate the Cam-Coordinates of the Cam-Profile, then, click Inner or Outer again, to calculate the Cam-Coordinates of the Cam-Profile you actually want. See STEP File Options.
		Copy the Cam-Coordinates to your clipboard
		If Cam Option in is Groove or Negative Groove, click to toggle between:
		Calculate Cam-Coordinates for the Inner Cam-Profile. Calculate Cam-Coordinates for the Outer Cam-Profile. Calculate Cam-Coordinates for the Pitch-Curve (XY-Points only).
		Click to toggle how we calculate the Cam-Coordinates.
		Calculate as XY-Points You enter the # Points (number-of-Points) We calculate the XY Coordinates of the Cam-Profile for the number-of-Points at equal increments of the Master Machine Angle.
		Calculate as BiArcs (see BiArcs) You enter the BiArc Error We calculate the BiArcs so that the maximum error between the cam we calculate and the true Cam-Profile (we also calculate!) is less than, or equal to, the BiArc-Error.
		Before you click this button, make sure that SOLIDWORKS is open and the active SOLIDWORKS document is a part document (.SLDPRT).
		We export the BiArcs to SOLIDWORKS as Arc sketch entities, OR We export the XY-Points to SOLIDWORKS and instruct SOLIDWORKS to use the XY-Points to add a Curve feature. In a SOLIDWORKS sketch, you can use Convert-Entities to convert the Curve feature to a Spline sketch entity. See also Note 4
		Usually, we calculate for you the XY Points automatically Usually, we calculate for you the Bi-Arcs automatically, but it takes more time to complete. If the Traffic-Light is RED, click the Traffic-Light icon again.
		Display a preview of the Cam-Profile.
		Read-only - the cam is “Open” or the cam is “Closed”.

Options for: Save as .STEP file-type

Edit these parameters before you save a cam as a STP (STEP) file.

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS

- Front Face, Back Face - the face to cut the Groove-Cam into the Cam-Plate (see more below)

- Dimensions of the Cam-Plate (see more below)

- Schematics to indicate the Cam type, and if the Plate-Radius and Bore-Radius are suitable (see more below )

- Stationary Cam only - enter an X-Offset and Y-Offset to move the center of the Cam-Plate (see more below ).

- Min(minimum) Inner-Cam and Max(maximum) Outer-Cam (read-only) - radii of the Inner and Outer Cam-Profiles. They should help you specify the Plate-Radius and Bore-Radius (see more below )

Dimensions for STEP file ONLY

These images show the features of a Groove-Cam that has been exported and opened in SolidWorks:

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS-StepDims

MD-Dialog-2DCam-CamCoordinates-GrooveDepth

Cam-Depth

The depth of the Groove Cam cut into the Cam-Plate. The width of the Cam-Flanks.

Minimum Plate-Depth – Cam-Depth ≥ 2 mm

MD-Dialog-2DCamCoordiantes-STEP-Cam-Radius

Plate-Radius

The radius of the Cam-Plate, when you select: Outer or Groove-Cam

Bore-Radius

The radius of the hole through the center of the Cam-Plate

Plate-Depth

The total depth, or thickness, of the Cam-Plate.

Schematics of Cam type; Are the Dimensions OK or Not-OK?

MD-DIALOG-CAMCOORDINATES-STEPFILEOPTIONS-StepDims

Status of Cam, Blank-Radius and Bore-Radius relative to Cam-Size

The Plate-Radius parameter applies to Outer and Groove Cams only

The Bore-Radius parameter applies to all Cam types

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-BoreOK-

Groove-Cam

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

Groove-Cam

Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

Groove-Cam

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Groove-Blan2Sm-Bore2Bg

Groove-Cam

Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer Cam

Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Inner-Blank0-Bore0

Inner-Cam ONLY

Plate-Radius is 0mm

Bore-Radius is 0mm - the Cam does not include a Hole through its center

MD-Dialog-2DCamCoordiantes-Inner-BlankOK-BoreOK

Inner Cam ONLY

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

Inner-Cam ONLY

Plate-Radius is NOT OK - this dimension is ignored with Inner Cams

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

You can save the STEP file.

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

Inner-Cam ONLY

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner Cam

You can NOT save the STEP file.

MD-Dialog-2DCamCoordiantes-Outer-BlankOK-BoreOK

Outer-Cam ONLY

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

MD-Dialog-2DCamCoordiantes-Groove-Blank2Sm-BoreOK-

Outer Cam ONLY

Plate-Radius is NOT OK - it is less than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

You can NOT save the STEP file.

MD-Dialog-2DCamCoordiantes-Groove-BlankOK-Bore2Bg

Outer-Cam ONLY

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is NOT OK - it is greater than the Minimum Radius of the Inner Cam

You can save the STEP file.

MD-Dialog-2DCamCoordiantes-Ng-Groove-OKOK

Negative Groove-Cam

Plate-Radius is OK - it is greater than the Maximum Radius of the Outer Cam

Bore-Radius is OK - it is less than the Minimum Radius of the Inner Cam

Minimum/Maximum Radius of Cams, Offset X and Offset Y.

•Min Inner-Cam - Minimum radius of Inner Cam

•Max. Outer-Cam - Maximum radius of Outer Cam (see also )

These values are useful to know when you want to make sure there is a minimum difference between the:

•Bore-Radius and the minimum radius of the Inner Cam.

•Plate-Radius and the maximum radius of the Outer Cam.

X-Offset and Y-Offset

When the Cam is stationary, enter an X-Offset and Y-Offset to move the center of the Cam-Plate relative the 0,0 of the Mechanism-Plane / Base-Part.

MD-Dialog-2DCamCoordiantes-STEP-No-Offset

X Offset = 0, Y Offset = 0

Read-only if the Cam is a not stationary.

Image left:

Blank-Radius and Blank-Bore with X-Offset = 0 and Y-offset = 0

X Offset = 20, Y Offset = 30

Image left:

Blank-Radius and Blank-Bore with X-Offset = 20 and Y-offset = 30

The maximum radius of the Blank-Bore can be increased, and the minimum radius of the Blank-Radius can be decreased.

Notes:

Note 1: When the Cam-Part for a 2D-Cam is a rotating-Part (e.g. a Cam-Shaft), make sure that the start-Point of the rotating-Part is at the Pin-Joint.

Note 4: Cam-Data and SOLIDWORKS.

When you export the Cam-Profile directly to SOLIDWORKS, the Cam will be coplanar with the Front-Plane of the SOLIDWORKS part document.

To move the Cam-Profile to a different Plane - XY-Points:

1.Calculate the Cam-Profile as XY-Points

2.Save it as a SLDCRV file-type.

3.Open the SLDCRV file in EXCEL - the Cam-Coordinates use the A, B, and C columns for the X, Y, and Z coordinates, respectively. The Z coordinates are all 0s.

4.To move the Cam to the:

a.TOP Plane: Move the C column to the D column, the B column to the C column, and the D column to the B-column (that is, swap the B and C columns)

b.RIGHT Plane: Move the C column to the D column, the B column to the C column, move the A column to the B column, and the D column to the A column (that is, swap the A and C columns)

c.(and/or) To mirror the cam: Multiply the X-column data by –1

5.Save the data TEXT (Tab delimited) (*.txt).

6. Close EXCEL

7.Use Windows File Explorer to rename the file-name.txt to file-name.SLDCRV

8.In SOLIDWORKS, do Insert > Curve > Curve Through XYZ Points... and browse to file-name.SLDCRV

To move the Cam-Profile to a different Plane - Bi-Arcs:

After you export the BiArcs to SOLIDWORKS, you can Right-Click the BiArcs sketch, and select 'Edit Sketch Plane' to move the sketch to a different Plane.

Note 5: The Cam as BiArc Data has six columns:

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

Degrees

End Caps relate only to Slot-Cams, also known as Linear-Cams, or Ramp-Cams. Top-Tip - Save a Slot-Cam as a STEP file if it will not transfer to SolidWorks.
End-Caps - Show	Show or Hide End-Caps
	End-Caps work well when the independent axis to the Follower moves in one direction only - see image “End-Caps - Show” If the independent axis changes its direction in the middle of its travel, you see False End-Caps in the middle of the Slot-Cam. - see image: “Slot-Cam with 'False' End-Caps”. Before you export Cam-Coordinates we recommend you add a dummy slot-cam - and move the main axis of the Slot-Cam in one direction at Constant-Velocity, over one machine-cycle. To make sure the Constant-Velocity is correct: 1.Connect a wire from a Linear-Motion-FB to a Gearing FB 2.In the Gearing FB, enter a Gearing Ratio = Linear Travel distance of Slot-Cam / 360). 3.Connect a wire from the Gearing FB to the Motion-Dimension FB as the motion of the Slot-Cam. As the MMA increases from 0 to 360, the Cam travels from 0 to Maximum Travel distance of Cam (mm).
Slot-Cam with 'False' End-Cams
End-Caps - Hide

	The cam-coordinates have been calculated. The Radius of the Follower-Roller × % Cam RoC Soft-Limit is greater than the minimum Radius-of-Curvature - see 2D-Cam dialog
	The cam-coordinates have not been calculated - Usually after you change from # Points to BiArc Error, or vice-versa.
	It is not possible to calculate the cam-coordinates correctly, Possibly because of undercutting.
	The cam-coordinates have been calculated. The Radius of the Follower-Roller × % Cam RoC Soft-Limit is less than the minimum Radius-of-Curvature - see 2D-Cam dialog - Undercutting is possible.

Calculate, Display, and/or Save the Cam-Coordinates:
	•Inner Cam-Profile ONLY
	•Outer Cam-Profile ONLY
	•Groove-Cam If you select Groove-Cam AND if you toggle to XY-Points, then you can also toggle to calculate the Pitch-Circle coordinates.
	•Negative-Groove The Negative-Groove option applies only when you save the Cam as a STEP file-type - see . The STEP file is the space filled by the path of the Follower-Roller along the Cam-Profile (plus Radial Clearance). Note: This is not the same as a Rib Cam. You need to model a Rib-Cam with Follower-Rollers, with one each side of the Rib.

Dialog: Cam Coordinates

Dialog: Cam Coordinates

Cam-Data FB > Cam-Coordinates

2D-Cam Work-flow

Cam-Data dialog: Cam-Coordinates

Status of Cam, Blank-Radius and Bore-Radius relative to Cam-Size

Dialog: Cam Coordinates

Dialog: Cam Coordinates

Cam-Data FB > Cam-Coordinates

2D-Cam Work-flow

Cam-Data dialog: Cam-Coordinates

Click icon to switch between XY-Points and BiArcs.

Status of Cam, Blank-Radius and Bore-Radius relative to Cam-Size