Constraints and Joints Creation

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Constraints and Joints Creation

 

Go to File arrowDCS Save Management.

Select the Lesson_4 Manual Gear Shifter Asm.CATProduct and select [Save As...].

Navigate to a New folder and rename to "Lesson5" that will be easily accessible later.

Click [Propagate Directory] to save a copy of the CATPart files to the new folder.

In the Save As dialog, rename the Product to "Lesson_5 Manual Gear shifter Asm" and click [Save].

In the Save Management dialog select [OK] to save the CATIA Product under its new name. The model is not saved until you click OK.

Go to [File] arrowDCS [Save As].

In the Save a Copy dialog, enter "Lesson_5 Manual Gear shifter Asm." for the File Name, make sure the Type is set to Assembly (*.asm), then click [OK].

In the Assembly Save a Copy dialog, click [Save Copy and Open] to save the assembly under its new name, and open the newly saved assembly.

Close the 3DCS Model Navigator and Creo window for Lesson_4 Manual Gear shifter Asm.

Click DVTI_dcsUpdateModel Update Model in the new window for Lesson_5 Manual Gear shifter Asm.

Go to [File] arrowDCS [Save As].

In the Save As dialog, enter "Lesson_5 Manual Gear shifter Asm" as the new File name and make sure the type is set to Part Files (*.prt).

Click [OK] in the Save As dialog.

Click DVTI_dcsUpdateModel Update Model.

Go to [File] → [Save As].

In the Save as dialog, enter "Lesson_5 Manual Gear shifter Asm" for the File Name, and make sure the Type is set to Assembly (*.asm).

In the Assembly Save as dialog, click [Save Copy and Open] in the bottom left of the dialog to save the assembly under its new name, and open the newly saved assembly.

Click Update Model in the new window for Lesson_5 Manual Gear shifter Asm.

Click the MC Application Button Icon Application Button then select MC 7500 Save As Icon Save As.

Change the File Name to "Lesson_5 Manual Gear Shifter Asm"and make sure the Type is set to WTX DATA(*.wtx)

Click [Save] in the Save As dialog.

 

For any model it is good practice to start the subassembly moves/constraints first followed by main assembly.

 

Pivot Sub-Assembly

 

This section will focus on creating constraints for the Pivot Assy first.

 

Click DVTI_movelist Moves in the Model Creation toolbar to create moves and the select Pivot Assy from the tree.

 

clip0185

 

Make sure the sub assembly name is displayed correctly at the top left corner and then proceed to add the constraints to the sub assembly.

Select Coincidence Constraint from the drop down menu and click [Add Mechanical].

 

clip0186

 

Name the constraint "Axis Select Pin to Pivot".

Click [+] to add a feature into the Object Features list.

Add the Pin Surface on the Select Pin.

Click [Close] in the Select dialog.

Click [+] to add the hole in the Pivot to the Target Features list.

Click [Close] in the Select dialog.

 

MVM_Tutorial_Coincidence Pivot Asm Features

 

MVM_Tutorial_ MC move lever axis

 

Click the Settings tab and change the Allow Drop DOF setting to Yes. This will need to be done for all Coincidence Constraints that will be created in the model.

 

drop dof setting MVM tutorial MC

 

Click [OK] to create the move.

From the Moves dialog select Contact Constraint from the drop down list and click [Add Mechanical].

Rename the constraint “Surface Contact Select Pin to Pivot”. Select the surfaces under object and target list as shown below.

 

 

MVM_Tutorial_Contact Pivot Asm Features

 

MVM_Tutorial_ MC move lever surface

 

 

Click [OK] to create the move.

 

It is a best practice to create a Fix Together Constraint for the sub assembly parts as the last move, which improves the analysis speed. This is an optional move but is added below.

 

From the move list select Fix Together Constraint and click [Add Mechanical]

Rename the Constraint "Fix Together Select Pin and Pivot"

[Add] Select Pin and Pivot by clicking on them in the graphics window.

Click [Close] in the select dialog.

The completed dialog should look like the image below.

 

MVM_Tutorial_ MC move lever fixtogasm

 

Click [OK] to create the move.

Click [OK] to close the Moves dialog

Click DVTI_dcsNominalBuild Nominal Build to see the parts build using the constraints.

Click DVTI_dcsSeparate_SP Separate.

Click animate Animate and step through each move.

 

Lever Assembly

 

Click DVTI_movelist Moves then click Lever Assy from the tree to start creating moves for the Lever Assy.

Follow the steps above to create a Coincident Constraint and Contact Constraint between the Lever Pin and the L Lever. Finish the Lever Assy constraints with a Fix Together Constraint.

Use the features seen below for the Coincident Constraint and Contact Constraint, respectively. Be sure to set the Allow Drop DOF setting to Yes in the Coincident Constraint.

 

MVM_Tutorial_Lever Asm Features

 

The completed moves list should look like the image below.

 

MVM_Tutorial_ MC move list lever asm

 

Click DVTI_dcsNominalBuild Nominal Build. The two sub assemblies should build together.

Click DVTI_dcsSeparate_SP Separate.

Click animate Animate and step through each move.

 

Creating Main Assembly Constraints

Click DVTI_movelist Moves from the toolbar and select the top product to open the Move dialog.

 

clip0194

 

Select Fixed Constraint from the Move list and click [Add Mechanical].

This will open the Fixed Constraint dialog.

 

MVM_Tutorial_ MC move fixempty

 

Name the Move "Fix Frame".

Click [Add] and select the Frame from the Graphics. Click [Close] in the Select dialog.

The completed Fixed Constraint should look like the image below.

 

MVM_Tutorial_ MC move fix

 

Click [OK] to save and close the Fixed Constraint.

 

Move Mounting Block to Frame

 

The Mounting Block can be fully constrained to the Frame with 3 more Constraints.

Create one Contact Constraint and two Coincident Constraints using the features highlighted in the images below.

Change the Allow Drop DOF setting to Yes for all Coincidence Constraints.

 

MVM_Tutorial_Block to Frame Feature1

 

 

MVM_Tutorial_Block to Frame Feature2

 

 

 

MVM_Tutorial_Block to Frame Feature3

 

The completed Move dialog should look like the image below.

 

MVM_Tutorial_ MC move list7

 

After assembling the Mounting Block to the Frame, create a Fix Together Constraint for the two parts.

 

MVM_Tutorial_ MC move fix tog

 

Moving Pivot Assembly to Mounting Block

 

The Pivot Assy can be fully constrained to the Mounting Block with 2 more Constraints.

Create one Coincident Constraint and one Contact Constraint using the features highlighted in the images below. Be sure to change the Allow Drop DOF setting to Yes for Coincident Constraints.

Notice that selecting features from the Pivot will add the Pivot Assy in the Move Part list which will move the whole assembly to the Mounting Block.

 

MVM_Tutorial_Pivot to Block Feature1

 

MVM_Tutorial_Pivot to Block Feature2

 

MVM_Tutorial_ MC coin move partpng

 

MVM_Tutorial_ MC move list3

 

Moving Stick to Pivot Assembly and Frame

 

The Stick can be fully constrained to the Pivot Assy and Frame with 3 more Constraints.

Create one Coincident Constraint and two Offset Constraints using the features highlighted in the images below.

 

MVM_Tutorial_select pin to stick

 

 

The Offset Constraint between the Stick and Pivot will utilize an offset of 0.2mm between the features shown below.

 

MVM_Tutorial_Stick to Pivot feature

 

The offset value can be set in the Settings tab of the Offset Constraint dialog.

 

MVM_Tutorial_ MC offset2

 

Complete the Offset Constraint for the Stick to Frame with an offset value of 5mm using the features in the image below.

 

MVM_Tutorial_Stick to Frame feature

 

 

Up to this point, the completed list of moves should look like the image below.  

 

clip0192

 

Moving Link to Pivot Assembly and Lever Assembly

 

The Link can be fully constrained to the Select Pin and Lever Assy with 2 Constraints.

Create two Coincident Constraint using the features highlighted in the image below.

Based on the geometry of these features, we will turn the float off for both of the Coincident Constraints. These are meant to be snap features with no float available. This can be done in the Floating tab.

 

 

MVM_Tutorial_Link moves

 

Up to this point, the completed list of moves should look like the image below.  

 

clip0191

 

Move Lever Assembly to Frame

 

The Lever Assy can be fully constrained to the Select Pin and Lever Assy with 2 more Constraints.

Create one Offset Constraint using the features highlighted in the image below with an offset of 5mm.

 

MVM_Tutorial_Lever and Frame features

 

MVM_Tutorial_ MC offset comp

 

MVM_Tutorial_ MC offset value

 

Next add a DVTI_RevoluteJnt Revolute Joint. The Revolute Joint will allow an axis and a plane to be constrained in one move.

Select Revolute Joint from the move list and click [Add Mechanical].

 

MVM_Tutorial_ MC Revolute empty

 

Rename the move to "Revolute Lever Assy to Frame"

Select the highlighted hole from Lever Assy and the hole from Frame.

Similarly select the highlighted planes from Lever Assy and then Frame.

 

MVM_Tutorial_Revolute  Features

 

MVM_Tutorial_ MC Revolute comp

 

Click [OK] to save and close the Revolute Joint dialog.

The completed move dialog should look like the image below.

 

MVM Completed Moves Dialog

 

Click DVTI_dcsNominalBuild Nominal Build to see the parts build using the moves.

Click DVTI_dcsSeparate_SP Separate.

Click animate Animate and step through each move.

Save the model.