Summary of this Step

We add the elements to specify the motion of the Tool-Part along the Slide-Joint.

In MechDesigner :

1.We add a Motion-Dimension FB to the Slide-Joint

The Tool-Part becomes, in MechDesigner Terminology, a Slider.

2.We add two more FBs: a Linear-Motion FB ('Clock') and a Motion FB.
3.We connect the three FBs together with wires.

In MotionDesigner :

4.We add and edit a motion so that it is a 'Rise-Dwell-Return-Dwell' [R.D.R.D.] motion type. The motion Rise = +50mm, and Return = –50mm.

In MechDesigner :

5.We link the new R.D.R.D motion to the Motion FB
6.Cycle the mechanism to watch the kinematic-chain move.

tog_minus        Video of this Step


Tutorial 6A-2

tog_minusAdd a Motion Dimension FB to the Slide-Joint


Click Add Motion-Dimension FB in the Kinematic-FB toolbar


The Command-Manager tells you which elements to select.

The full message in the Command-Manager - if you expand the width of the vertical bar of the panel is:

Click in turn: a Slide or Pin-Joint; a Green Line or Point; a Blue Line or Point.


Other terms for solved are kinematically-defined, and Green. Other terms for free are kinematically-undefined, and Blue.

To add a Motion-Dimension FB to a Slide-Joint, one of the two Lines that make the Slide-Joint must be a sketch in a solved Part.

The other Line must be a sketch in a free Part.

The Points at the ends of the solved Line are also solved.

The Points at the ends of the free Line are also free.


STEP 1: Click the Slide-Joint1s-red

The Slide-Joint is represented by rectangles along each Line in the Slide-Joint, or the Slide-Joint element in the Assembly-Tree.

Click the narrow rectangle or the wide rectangle

STEP 2: Click a Point -  Solved (Green)2s

Click a solved Point 2s at one end of the solved Line in the solved Base-Part.

STEP 3: Click a Point - Free 3s

Click the Origin of the CAD-Line in the free Part.


Step 3 is complete

The image shows the Command-Manager with the elements in the boxes for the Add Motion-Dimension FB.

STEP 4: Click OK in the Command-Manager.



Step 4 is complete.

MechDesigner adds the Motion-Dimension1s-red between the Points in the Slide-Joint. The dimension is positive or negative.

You will usually want to edit the Base-Value

The Base-Value is the value the Motion-Dimension has when a wire is not connected to its input-connector.

We edit the Base-Value with the Motion-Dimension dialog-box.

STEP 5: Edit the Motion-Dimension to open the dialog-box

Double-click the dimension extension lines or arrowhead

- or -

Right-click the FB icon, then

Select the Edit Element icon, in the contextual sensitive icon palette.


The Motion-Dimension dialog-box opens.

Edit the 'Base-Value'1s-red

- or -

Edit the 'Base-Value + Motion Value'2s


Step 5 is complete in the near image.

Edit the 'Base-Value' to 40mm

In the image, ignore the Base-Value[75], and the Motion-Value [0.1599...].

tog_minusAdd a Motion FB and a Linear Motion FB


These Function-Blocks are very easy to add to the graphic-area.

In the Kinematic-FB toolbar

STEP 6: Click the Linear-Motion FB1s-red and then
Click in the graphics area.
STEP 7: Click the Motion FB2s and then
Click in the graphic-area.

Step 7 is complete. The Linear Motion FB1s-red and the Motion FB2s are in the graphic-area.

You now need to connect the Function-Blocks together with wires.

tog_minusConnect the Function-Blocks together with wires


STEP 8: Connect the Function-Blocks, as shown1s-red2s

Drag from an 'output-connector' to an 'input-connector'.

Step 8 is complete.

STEP 9: Use Run menu > Cycle
- or -
Use the keyboard shortcut: 'C'

tog_minusDesign a New Motion in MotionDesigner


The Default Motion

When you add a Motion FB, MechDesigner links the left-most Motion name-tab in MotionDesigner to the Motion FB. This is the Default motion.

The default motion has four segments1s-red2s3s4s. The segments make a Rise-Dwell-Return-Dwell motion.

The Rise Segment1s-red is from 0 to 90. The Return Segment3s is from 90 to 0 [mm or degrees].

Therefore, Base-Value in the Motion-Dimension FB is 40mm, the Slider moves from 40 to 140mm.  Usually, the default motion is not the motion that you need.


Add a new Motion

STEP 10: Use Tools menu > Show/Hide MotionDesigner to show MotionDesigner

In MotionDesigner, add a new Motion name-tab.

STEP 11: Click Add Motion1s-red


STEP 12: Rename the Motion to 'Tool Motion'1s-red

To rename a Motion in MotionDesigner, you must open and use the Active-Motion-Settings dialog


<<< MotionDesigner > Edit menu > 'Open Active-Motion-Settings' dialog



STEP 13: Edit the Motion so its Rise is 50 2s

[See below, for instructions to edit the motion, or see below]


- or -

Tutorial 2: Introduction to the Flexible Polynomial Segment


Open the Blend-Point Editor

Select Segment 2 with the Next and Previous arrow buttons.

In the End Position box, enter 50, and then use the Enter key on your keyboard

Select Segment 3 with the Next arrow button.

In the End Position box, enter 50, and then use the Enter key on your keyboard

Each segment can take 90º of the MMA.

Step 13 is complete.

tog_minus        Link 'Tool-Motion' to the Motion FB


STEP 14: Double-click the Motion FB in the graphic-area, to open the Motion FB dialog-box

or See How to open a dialog-box

See dialog to the left.

STEP 15: Click the 'Select Motion' drop-down box and select 'Tool Motion' in the list 1s-red
STEP 16: Click OK-tiny-13-17
STEP 17: Now, again, Run > Cycle to watch the new motion.

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