Modelling of an Automotive IP trim using ANSA

Objective:

• To take out the mid surface of the IP subtrate.
• To mesh the component with the given quality criteria.

About the model:

An Instrument Panel(IP) also called dashboard or fascia,is usually located directly ahead of a vehicle's driver,displaying instrumentation and controls for the vehicle's operation.

Above shown plastic component is the instrument panel and it consists of 

• Speedometer-Shows speed of the vehicle.
• Tachometer-Shows engine rotations.
• Odometer-how many kms/miles your has car travelled in its lifetime.
• Fuel Guage
• Gear Display
• Turn signal indicators
• Active system Lights

 As this component is made of plastic and having thickness below 5mm, we need to take the mid surface of the component.

Procedure:

1.Geometry CleanUp:

We import the model into ANSA.Model will be having disturbed faces detached from one another.

At first we need to refine the model by setting up the nodes.A model can be refined by changing the distance between perimeter and macros.

To set the length,we go to Mesh>Perimeters>Length and change the node length for both perimeters and macros as 1mm.

Here 1mm is set  because less difference beetween lengths will give more finer model.

So,a fine model is obtained.

Then We click on Topo>Faces >Topo to paste the surfaces together.

We obtain a model like this,

Further,We check for gemometry in Tools>Check>Geometry and we check for

• Unchecked surface
• Collapsed cons
• Triple Cons
• Needle Faces
• Overlap Faces 
• Cracks
• Single cons

After executing,we get upto 747 geometrical errors.

Most of the faces can be fixed  automatically using ANSA's built in option(Right click by selecting a geometrical issue and  click on Fix).

Some of the geometrical issuses should be corrected manually like deleted surfaces ,triple cons etc.

After correcting geometry,we check the geometry again to clarify if the  geometry is clean.

There are no geometrical errors found and the status is green.So we proceed for mid surfacing.

2.Mid surfacing:

Mid surfacing is the method of taking mid surface of the model.

We have several mid surface options on ANSA which includes automatic and manual mid surfacing.

Here the mid-surface is achieved manually 

We use

Faces>offset

Faces>middle

Faces>extend etc.

Here are some pictures after taking mid surface,

We need to assign different properties for different mid-surfaces now.

So to assign PIDs we go to Topo>Faces>set PID.

and we assign different thickness for different faces having different thickness.

Then we mesh the component using spotmesh.

3.Meshing:

Meshing is the representation of a geometric model as a set of elements.

Before meshing ,we need to set mesh parameters and quality criterias.

Since both mesh parameters and quality criteria are given,

We mesh the components suing spot mesh.

As we observe the model,some feautures have lesser width or length than the given minimum length.So in these cases we achieve 70% to 90% feauture capturing by re-arranging the cons.

Some examples are shown here.

Then we mesh the component using spot mesh.

As the mesh generated,It will contain several off elements.

These off elements can be removed by reconstructing,smoothing the mesh.

Several options like Split,Swap ,Join,Paste,Move is used to achieve a good mesh flow.But in some places where 2 adjacent triple cons are present and they fall under minimum length criteria,Those areas are left as it is as shown below,

So the process of meshing and correcting the mesh is done to get a better quality of mesh.

Conclusion:

Automatic mesh by ANSA was not happening,so manual mesh should be preffered.

Quality cannot be maintained on every surface because some faces fall under the minimum length quality criteria.

Google Drive link:

 https://drive.google.com/file/d/1QaFM3vteP8B63Z4lBwMYW31ZAv_lbc2y/view?usp=sharing