<< Click to Display Table of Contents >> Navigation: MechDesigner Reference & User Interface > 2.2 Mechanism-Editor: > Kinematic elements > Add Slide-Joint |
![]() Slide-Joint in MechDesigner |
![]() Slide-Joint - THK |
![]() Slide-Joint in SOLIDWORKS |
Slide-Joint : |
A Slide-Joint forces a Line* in a Part to be collinear with a Line* in a different Part. A Slide-Joint removes two degrees-of-freedom from the model. A Slide-Joint allows only rectilinear translation motion between two parts (rigid bodies). |
Prismatic Joint : |
The kinematic and equivalent term for a Slide-Joint. |
Kinematics-Tree : |
Joints in a Dyad use the letter P to represent a Slide-Joint. - e.g. R-R-P |
* Line or CAD-Line. |
![]() Slide-Joint |
The symbol for a Slide-Joint:
* The Positive-Direction is important if you want to add a motion to the Slide-Joint. See Positive direction of Slide-Joints and Motion-Dimension. |
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IMPORTANT: To calculate reaction Forces on a Slide-Joint: The length and position of the Lines should be equivalent to the actual design. |
![]() Select two Lines ![]() A New Slide-Joint |
STEP 1: Start the Add Slide-Joint command
STEP 2: Click the two(2) Lines
The two(2) Lines become collinear to add the Slide-Joint. The Positive Direction of the Slide-Joint is identified by the small arrowhead. If the Select-Elements dialog-box opens, see Slide-Joint Special Case
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Video: Add Slide-Joint - Special-Case
Special Case: two(2) or more collinear Slide-Joints
Frequently, a machine design has two(2) collinear Slide-Joints between three Parts. We must decide which two(2) Lines from which of two(2) Parts we want to select for each Slide-Joint. For example: There are a total three Parts and we would like to join all three Parts to be collinear. We must add two(2) Slide-Joints: Slide-Joint#1 is between Lines 1 & 2 (in Parts 1 & 2), Slide-Joint#2 can be between: Option A: Slide-Joint#2 between Lines 3 & 1 (in Parts 3 & 1) Option B: Slide-Joint#2 between Lines 3 & 2 (in Parts 3 & 2) When to do Option A or Option B becomes important when you need to also add Motion-Dimension FBs to specify the motions of the two(2) Parts. |
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Preparation example:
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STEP 1:Add Slide-Joint
STEP 2:Select two(2) Lines:
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We have clicked a total of three(3) Lines. However, the Slide-Joint is between two(2) Lines. Therefore, there is ambiguity as to which two(2) Lines you want for the Slide-Joint. Ambiguity: when MechDesigner is not sure which element to select. |
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When there is ambiguity as to which elements to select the Select Elements dialog-box opens. <<< Select-Elements dialog-box
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![]() Two Lines are Compatible |
STEP 4: Select the TWO Lines in the Select-Elements dialog
You can select: •CAD-Line2 and Line3 are compatible (image above) OR •CAD-Line2 and CAD-Line are compatible (image left) You cannot select: • Line3 and CAD-Line are NOT compatible (image below) Why not Line3 and CAD-Line ? There is a Slide-Joint between these two(2) CAD-Lines already. |
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![]() Two Lines are Compatible |
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![]() Two Lines are NOT Compatible |
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STEP 5: Close the Select-Elements dialog-box
There are now two(2) Slide-Joint between three(3) Lines |