Project 1

A wire harness, also commonly referred to as a wiring harness, is an exterior sheath used to cover some types of electronic wires. Generally, wiring harnesses are made of thermoplastic or thermoset materials that can help protect the cables from the environment.

OBJECTIVE :

• The project's objective is to route the wiring harness on the given Engine and prepare a flattened view drawing in CATIA V5. All types of packaging rules have to be considered while routing the harness. Also, Industry best practices should be demonstrated in design. All the necessary details like clearance, clipping/clamping selection, harness fixing requirements, and harness continuity should be provided to design a wiring harness.
• The above figure shows the 16-valve Bugatti Engine where 8 cylinders are placed on the right and 8 on the left sides.
• There are 16 injectors where 8 injectors are used for 8 cylinders on the right side and 8 injectors for another 8 cylinders on the left side.
• Also, there are 4 cam-shaft sensors, so there are a total of 20 sensors that we have to connect electrically.
• Generally, 4-pole connectors are used for fuel injectors of the engine.
• The engine will also have an interconnection connector connecting the engine to other parts of the vehicle. We will be using a 12-pole electrical connector with a mounting clip feature as an interconnection connector.
• The plastic guiding channel used in this harness should be made of a material that can withstand at least 150 degrees Celcius.
• The bend ratio for all bundle segments.

DESIGN METHODOLOGY:

• Download the engine CAD data and required connectors CAD data from the given source.

Available connector 3D data can be used, or you can download the connectors from www.te.com

• Download the required Connectors from the source and convert the mechanical connectors electrically by using the electrical part design workbench by following the below steps.
• First download the connectors and mounting clip from the given link source.
• Get into the mechanical part workbench to create the required geometrical parameters. Create a connector connection point and bundle connection point on the required sides of the CAD part.
• Create an axis system on the connector connection point in such a way that the Y coordinate faces normally to the connector face, X coordinate faces towards the locking mechanism and Z coordinate faces to the top.
• Create cavity connection point for connectors having the cavity for mounting clips
• Using the geometrical parameters created,
• Define part as an electrical connector.
• Define bundle connection point.
• Define connector connection point.
• Define cavity connection point.

Creating the Main Assembly:

Context assembly is nothing but the product file that contains the engine 3D-CAD data and the engine harness geometrical bundle. Here the geometrical bundle product contains all the connectors and other mounting equipment, clips and clamps which are electrically defined for the assembly. Sheet metal L-clamps are added in the main context assembly.We need to switch into the electrical harness assembly workbench and the Geometrical bundle product file should be electrically defined using the Define Geometrical bundle option before adding any parts to it.

The Given V16 engine 3D-CAD model requires a total of 23 connectors to be placed on it and an interconnection connector for the engine wiring harness assy. The connectors used in this engine are as follows

• 8 numbers of connectors are required on the fuel injector sensors on each cylinder head, i.e.; a total of 16 fuel injector sensor connectors are needed.
• A total 4 numbers of cam-shaft sensor connectors are needed.
• 1 neutral position sensor connector and 1-speed sensor connector on the gearbox housing.
• 1 engine coolant temperature sensor placed at the centre of the engine.

Adding 4 pole connectors to all fuel injector sensors as well as for the camshaft sensors.4 pole connectors should be added to the geometrical bundle using copy paste connector or directly imported from the catalog created earlier. Connectors can be added again by copy-pasting the 1st imported connector. Place the connectors on all the fuel injector sensors and cam-shaft sensors using manipulation tools like move, smart move, snap tool and also using the compass. Adding all the other connectors for sensors like coolant heat sensor, neutral position sensor, speed sensors

Placing the Interconnection connector and L-clamp support

However, the situation of interconnection connectors is not similar to device connectors. Interconnection connectors are not parked with any device but should be pared with the help of clips/clamps/sheet metal brackets etc. possible to the packaging conditions. Unparked connectors can create the following issues-

• Rattling noise
• Physical damage to connectors
• Uncontrolled harness routing
• Manual errors during assembly because of undefined parking.
• Assume the bundle connection from the chassis is coming from the right side of the engine. Therefore L-clamp is provided on the right side of the engine which provides proper support for the interconnection connector. Here the cavity clip is inserted into the hole provided on the L-clamp. Additional slack should be provided to the chassis bundle connecting to the engine harness interconnection connector to protect the wiring harness from vibrations caused during the vehicle operation. From the above pictures, we can clearly see that the L - Clip is mounted to one of the holes provided on the Engine block for the screw and it is rested onto the ribs so that it restricts its rotational movement during the tightening of the screw. Also, we can see that the Interconnection Connector has been placed and it is electrically connected to the cavity provided for it. The L-clip should be added to the main product as it is not a part of the Geometric bundle or the Wire harness bundle.
• Add P-clamps for proper Routing of the harness bundle
• Adding supporting components like p-clamps and firtree clips can help the harness bundle provide proper routing and also help to prevent the harness bundles from fouling from unwanted mechanical components.
• P - The clamp and the Fir Tree can be placed at the required locations to ensure the best possible routing for the harness bundles.
• The p – Clamps can be mounted to the holes provided on the Engine block in which the screws to tighten the Engine block.
• The Fir tree clips are positioned according to the requirement during the wire harness routing.
• After finalization of the routing, we can request the Engine design team to provide the holes for the Fir tree clips as per their location.

Routing the wiring harness to the connectors :

• Go to the electrical harness assembly workbench select the geometrical bundle command and select the geometrical bundle in the model tree. Then select the multi-branchable command to start the bundle routing and go to route definition.
• The bundle routing starts from the interconnection connector then to the P-clamps and to the guiding channels.
• Adding branching points wherever necessary using the add branch point command as shown below.
• Adding branches wherever necessary to connect the various connectors to the main branch as shown below using the add branches command and routing definition into it.
• To route the wiring harness through the guiding channels select the external curve and click on the line in the guiding channel.
• Add branching points to the wiring bundle and add branches to connect the wiring to the connectors at the injectors as shown below.
• Add a guiding channel top as shown in the image below.

Checking bundle continuity:

• In this step, first, we have to make sure that multi-branch able is selected then we have to go to Edit>Search>Advanced>Workbench-Electrical>Type-Bundle Segment>Attribute-Fully Connected
• Selecting the 'True' option will show all the connected bundle segments while selecting the 'False' option will show all the non-connected bundle segments.
• Here, we have selected the 'True' option and searched for results. All the bundle segments are highlighted showing that all the bundle segments are electrically connected.

FLATTENING HARNESS:

• In this step, to create a flattened view we have to work on the Electrical Harness Flattening workbench of Catia V5. We should also make sure that the flattening file is saved in the same folder where other files of harness assembly are saved.
• Before creating a flattening view, first, we have to define flattening parameters. Make sure that you select a Single line for the bundle segment and a double' line for protective covering.
• We have extracted the bundle assembly into the Engine Harness Flattening Product file and then flattened the file along the face of the interconnection connector as shown in the above figure.
• At this stage, for clarity, we have hidden the flattening diagram of the plastic guiding channels from the drawing view.
• we are creating a new drawing file and defining all the necessary drawing parameters. We have to insert the front view of the Engine Harness Flattening Product file into the Drawing file.

To convert.Catpat file into product file and save as .igs FILE:

After this process, it looks like as

CONCLUSION:

In this project, I have successfully routed the wiring harness for the V16 Engine assembly and the flatten-view drawing was prepared in CATIA V5. Various packaging rules and constraints were considered while routing the harness. After finalizing the wire routing, we can request the corresponding Engine design team to provide additional holes for the mounting of Fir tree clips.

https://drive.google.com/file/d/1cFsbVyUZq50Q1w7kR8Zt4z_FZiwWe52i/view?usp=sharing