Week 6

CAR RARE DOOR CONNECTIONS BY ANSA

AIM:The main aim of the project is to deploy all the connections to the car rare door model by ANSA.

OBJECTIVE:The objective of this project is to import the model,assigning PID for each part and deploy the connections where ever it is needed.There are different types of connections to deploy for differents parts.

METHODOLOGY:

• Import geometry.
• check for the errors.
• Assign PID for different parts.
• connect the model with different connections.

INTRODUCTION:

• A car door is a type of door , typically hinged, but sometimes attached by other mechanisms such as tracks, in front of an opening which is used for entering and exiting a vehicle. A vehicle door can be opened to provide access to the opening, or closed to secure it. These doors can be opened manually, or powered electronically. Powered doors are usually found on minivans, high-end cars, or modified cars.A vehicle typically has two types of doors: front doors and rear doors.
• Most vehicle doors are secured closed to the vehicle body with latches which may be locked to prevent unauthorized access from the exterior. There are a variety of car door locking systems. Door locks may be manually, or automatically operated, and may be centrally or individually operated. Also, they may be operated by remote control, with the transmitter often integrated into the main vehicle access / ignition key.

PROCEDURE:

Step 1: Import the model.

• After opening the ANSA,go to file command and import the model.

fig: Image showing the imported model.

STEP 2: CHECK FOR THE ERRORS

• After importing the model,do check for the geometrical errors.
• If any errors are present do it by automatically or by manually.

fig:Image showing for errors check in the model

STEP 3:ASSIGN PIDS

• As there are no errors,assign pids for each part.
• Select the each part seperately,go to the PROPERTIES tab in the List.
• Create one pid and apply it to the part.

• Likewise,sperrate each part from the model and assign PIDS.

fig:Image showing PIDS of the every part.

STEP 4:CONNECTIONS

• For connections we need mesh model.So,turn on the wire frame mode and go to mesh tab.
• Check that every part is meshed or not.
• The mesh should be in a good mesh flow.

NOTE:For this project the model is already meshed so we are proceeding with the connections.

TYPES OF CONNECTIONS:

1. RBE2 connection.
2. RBE2 cluster connection.
3. RB3 hexa RB3 connection.
4. RB3-Cbush-Rb3 connection.

• Apart from the above connections we also have Bolt connection which can be done automatically and manually.

RBE2 CONNECTION:Generally,this type of connection is used when there is a sheatmetal with is of single layer.We will have washer element,for which we need to create ZONE CUT for the particular part so that the weight is distributed uniformly.

• In the above image we can see that connection is applied for the nodes which are one step away for the hole perimeter.
• By creating Zone cut we notice that washer element is also taken into consideration and when any load is applied on the hole the weight is distributed uniformly taken into consideration along with washer element.

NOTE:Zone cut is not allowed when there are perimeters near to it.Whichmeans when the connections are near to the GREEN LINES then zone cut is not peferred,which is not a good practice.

• For RBE2 connection go to NASTRAN-ELEMENTS-RBE2 connection.
• Select RBE2 many nodes,select the nodes of the hole for which connection is to be deployed.
• After clicking middle click in the mouse,the connection is deployed in model.
• Save the connection in the new floder of Mdel browser.

fig:image showing RBE2 connection.

RBE2-CLUSTER:This type of connection is used when there are holes of differnet sizes but there centre of gravity is same.

• Go to NASTRAN -ELEMENTS-RBE2 and select the connection.
• Select the holes where the connection is to be deployed.
• For cluster connection the holes must be of different sizes with same centre of gravity.

fig:Images showing the cluster connection

• In the above we can observe that the master node for differnt holes is same.This type of connection is called as RBE2 cluster.

BOLT AND STEM CONNECTION:This connection is used when there are different parts is to be connected by a single bolt.For this type of connection the size and centre of gravity of the holes should be same.

• This type of connection can be done by Automatic or by manunal method.Where Automatic method will be time saver for the user.

METHOD:

• Go to TOPO tab in the ANSA interface.
• Select ON COG from POINTS table .
• Select the centre hole for which point should be created.
• Upon middle click the will be created.

Fig:Image showing creating pont fig:image showing 3d point

• A 3d point is created as centre for which connection has to be deployed.
• Now convert that 3d point into bolt connection by convert option.

• A 3d point will be created as Bolt connection.
• Now go to connection manager select the 3d point which we created.
• A new tab appears in which we need to select the parts and connection type.For parts go to their tabs and modify them by selecting F1 key and select the part.Like wise we can select maximum of 4 parts in ANSA.
• Then go to the BOLT connection type upon giving the search distance(user defined) and apply them.
• Then by realize the connection a Bolt and Stem connection is deployed.

• We can observe in the image that a BOLT STEM connection is deployed for the holes which has same size and are in same line.

RBE3 HEXA RBE3 CONNECTION: This type of connection is used for the SPOT WELD.When there are parts which are parallel to each otherand where there is no hole then SPOT weld connection is used.

• Go to ON COG in points,select the element where we need spot weld and creat a point.
• Convert that 3d point into spot weld by convert option.

• A new Spot weld point is created.
• Then go to connection manager select the spot weld point and select the parts.
• Now go to the RBE3 hexa RBE3 connection and give search distance.
• Upon realixing the connection is created.

fig:image showing the spot weld connection.

NOTE:For door handle part, mass element connection is required,create the RBE2 connection and give the mass by creating another node.

CREATING MASS:

• Go to NASTRAN deck-ELEMENTS-CONMI 2
• Select the node and give a mass of 100g .

fig:image showing mass of the node

RBE3-CBUSH-RBE3: This type of connection is used for the parts where there is a moment.In our model we are going to use it for the mirror part.This type of connection contains a seperate co-ordinate.But we need to convert it into global co-ordinate.

METHOD:

• First create a curve for the perimeter of the glass by selecting Feat2curve option in mesh tab.
• Select the perimeter of the glass correctly.

fig:Image showing cure fo the perimeter for the mirror

• Convert this curve to SPOT LINE by selecting convert-curve option.
• Make sure select the curve one by one and convert them induvidually.

fig:Image showing curve converting into spot line

• NOw go to convert manager and select the curve and the parts as same like above.
• Select RBE3-CBUSH-RBE3 give search distance as required and tick keep all branches option.
• Upon relizing the connection will be deployed.

• Like wise select each spot line and mention the parts correctly and realize the connection.

fig:Image showing CBUSH connection

NOTE:We can check in the database under elements that our CBUSH is deployed or not.If there is any small mistake also CBUSH connection will not be deployed.

fig:image showing individual coordinates of CBUSH connection

• Every CBUSH connection has individual corodinates.
• We should convert that individual coordinate into global coordinate.

CONVERTING INDIVIDUAL COORDINATE TO GLOBAL COORDINATE:

• Under database-elements select CBUSH.
• By double clicking CBUSH another tab will be opened.
• In search field do click orient and CID.

• Select all elements do right click on the mouse and do modify.
• In modify rules select ORIENT-With cord;CID to 0
• By clicking apply all the CBUSH connections change into global coordinate system.

fig:Image showing cbush connection in global coordinates.

BEFORE AND AFTER IMAGES OF MODEL:

LEARNING OUTCOMES:

• Got to know about connections.
• Able to do connections for any model.
• Learnt where to use which type of connections.
• Able to convert connection from local coordinate to global coordinate.

CONCLUSION:Hence from this project,we got to know how important for the model the connection has to be made.For any model the connections procedure is same as above.Missing one connection by mistake is taken into consideration but mmissing complete part is not taken into consideration.Therefore,the connections for the car rare window model is done.

LINK OF THE PROJECT: https://drive.google.com/file/d/1R4Zj43o1NTIyCJYaosjJY-ATRbTgo1Go/view?usp=sharing