Project 1

AIM- Route the wiring harness for the Bugatti V16 Engine assembly and prepare flatten-view drawing in CATIA V5.

OBJECTIVE:

• define all the connectors electrically and save it in the Catalogue. 
• place all the connectors and cavities at the required position and place P Clamps and Fir Tree clips at the required position by following the packaging rules.
• create the Wire Harness Routing as per required and create branch points wherever required and also by following the packaging rules.
• The objective of this project is route the wiring harness and prepare flatten-view drawing for the Bugatti V16 engine.
•  All types of packaging rules and constraints have to be considered while routing the harness.
• Industry best practices should be implemented in the harness design. 
• All necessary details like clearance/ clamping selection, harness fixing requirements, harness continuity should be provided in order to design the wiring harness.

Assumptions-

The wiring harness packaging rules and the industry best practices that have been followed to complete this project are as follows

• Provide clips/clamps as per requirement.
• Make sure that there is no any fauling case while designing the wire harness. Additional clips/ clamps may be used to avoid fouling.
• Provide additional slack if needed according to the surrounding and harness bending requirement. 5-10% slack is sufficient.
• Avoid routing over bolt and bolted joints to avoid harness puncture.
• Minimum distance between two branch points should be at least 50mm.
• Minimum distance between clip and branch point should be at least 25mm.
• Avoid routing on sharp edges or else provide protection over the harness.
• Follow the clearance distance and keep away the harness from heat generation components.
• Protection should be provided as needed according to surrounding temperature.
• Avoid direct support for harness on fuel lines routed in the engine.
• While using dummy connectors, ensure that whatever positions you are defining that are practical. Bundle diameters and another placements can be defined properly for the wire harness routing.
• Branch length should be greater than 50mm.
• Avoid too many sheet metal brackets on the engine. Try to use available threaded bosses on the engine or demand for it.
• The wiring harness should be easy to assemble and easy to access. 
• Use plastic guiding channels if needed.
• If the packaging area is too tight and there are many packaging constraints then we can think of creating harness channel which can be used to route and protect the wire harness effectively.

DESIGN METHODOLOGY:

• Create a product file as ' Assy Engine Harness Context' in which all the part and product files will be assembled which are required for the routing.
• Create another product file as 'Assy Engine Harness Geometric Bundle' where all the connectors are added to it and the final routing is a part of this product file.
• Now add the V16 Engine, Geometrical Bundle file and other required parts or products to our main ' Assy Engine Harness Context' product fil
• Electrically define all the connectors, cavity clips and channel part and define the Connector Connection Point and the Bundle Connection Point.
• After electrically defining each and every connector save it in the Connector catalogue so that it can be used later. 

 Engine Model Dawnload For Wiring Harness Routing:-

 Creating context assembly:-

A context assembly has to be created which will serve as the main assembly for engine harness. The context assembly will contain the 3D-CAD data for the Bugatti V16 engine and the Assy engine harness geometrical bundle. If any sheet metal brackets are required then they are added in this "ASSY ENGINE HARNESS CONTEXT".

Definr electrical device in electrical part design module :-

The 4-pole connector used for this harness assembly is "C-156389-1". The 3D CAD data for this connector was downloaded from TE.com. To define the connector electrically we should define the geometrical parameters, bundle-connection point, and the connector-connection point for the downloaded connector.

"C-156389-1"

Define Interconnecting Cunectors(C-776438)

 Adding connectors to the all 16 fuel injector sensors and 4 cam-shaft sensors

All the connectors have to be added inside the Engine harness geometrical bundle assembly. Manipulation tools along with a compass, snap, and smart move features should be used to locate all the 20 connectors in their desired locations. All the connectors are shown in red for clarity. 

First,

Connectors are located for the first 8-fuel injector sensors which are on the left side of the engine. Then they are located for the 4-cam-shaft sensors. At last, the remaining 8 connectors are added to the 8 fuel-injectors on the right side of the engine.

 Sheet-metal bracket for mounting interconnection connector:

A sheet -metal bracket has to be created in order to provide mounting for the interconnection connector. We have to make sure that the bracket is placed inside the context assembly outside the engine and harness geometrical bundle assembly. The bracket can be mounted on the existing bolt located as shown below. It has to be made sure that in the real-world application if we are using any existing bolts or screws then the design idea has to be discussed and passed by the engine design engineering team in order to make sure the proper functioning of the engine. This bracket should have a locking feature in the clockwise-direction so it does not rotate freely. The current engine design has a rib feature as shown below which can be used to our advantage as a locking feature. The edge of the bracket will sit on the rib thus locking the bracket in place. 

LOCATION OF THE P - CLAMPS :-

We have to mount 3 P-clamps also on the existing bolts of the engine so before that we have to define P-clamp electrically with geometrical parameters, entry and exit point on both left and right side of the P-clamp as shown in below figure. Here, we have mounted 3 P-clamps on the existing bolts of the engine for the wire harness routing as shown in above figure.we have mounted furr tree clip also for the smooth path to wiring harness routing towards guiding channel on both right and left side.

 

SOME IMPORTANT PACKAGING RULES TO BE CONSIDERED DURING WIRE HARNESS ROUTING AND PLACING OF THE CLIPS AND CLAMPS :-

• P - Clamps, Fir tree clips and other clips can be added to the Geometric bundle as they are electrically defined and are part of the Wire harness routing and should be provided with the Wire bundle package.
• The minimum bundle length should be 50mm.
• Enough slack should be provided so, that the wiring harness do not get damaged during the Engine rocking or starting condition.
• The wire harness routing should be done in such a way that it is easy in manufacturing and serviceability.
• The wire routing should be done keeping in mind the cost effectiveness of the bundle package.
• To avoid the harness routing and clipping in blind zones of the operator during the assembly and the service.
• Additional slack should be given according to the surrounding and harness bending requirements.
• To avoid giving excess slack and avoid giving slacks wherever not necessary.
• To provide proper slack at end connectors so that there will be no tension on the wire bundle.

Mounting of a plastic guiding channel :-

The Bugatti V16 engine has 8 fuel injectors on the left side and 8 fuel injectors on the right side of the engine. All these fuel injector sensors are located very close to each other. So, the best way to route the wires around them is by using a plastic guiding channel as they will help us organize all the wires very precisely and will reduce complex wiring harness routing. To mount the plastic guiding channels we would need some mounting provisions. The engine design team can be consulted and asked to provide mounting threaded holes or threaded bosses. 

The plastic guiding channel will be a two-piece molded plastic that will protect the wiring harness from surrounding high temperatures, wear and tear while providing nice aesthetics to the engine.There will be two different plastic guiding channels for this engine. One for the left and the other for the right side of the engine. It has to be made sure that proper clearance (at least 50 mm) is provided between the plastic channel and the exhaust pipes. The total thickness of the these channels is 25 mm.

Define plastic guide channel as a electrical equipment

where curves are define bundle  path and bundle  cunnection point  and  plane is define for bundle entey .

Engine with all mounting and guiding provisions:-

The image below shows all the 20 connectors, 2 plastic guiding channels, 3 P-clamps, and an interconnection connector mounted on the sheet-metal bracket.

 Locating the Guiding channel

WIRE ROUTING:

Adding branch point to the bundle segment at distance of 55mm from P-clamp as shown in below figure.

Route bundle segments from these newly created branch point to the 8 fuel-injectors connectors. Bundle diameter is assumed to be 1.5 mm.

In above figure, we are routed bundle segment from the newly created branch points to the 8 fuel-injector connectors. The bundle diameter is assumed to be 6mm.

Adding two branches from the created branch point to the cam-shaft connectors.

Completed routing to all the four cam-shaft connectors.

Similarly, we have done routing for the left side guiding channel also as shown in above figure.

 Redefining all the bundle diameters appropriately

All the bundle segments connecting to the connectors are 1.5 mm in diameter. Bundle diameter of the segments leading to the plastic guiding channels is 12mm.

Adding protective coverings, guiding channels top shell to the harness bundle.

Slit- COT tubes, cotton tapes are added on the wiring harness bundle as shown below. The top part of the plastic guiding channel will also be added at this stage. 

7mm and 16mm COT tubes (shown in orange pink) are added on top of the bundle segments as a protective covering. The start and end extremity for the COT tubes is assumed appropriately.

Checking Bundle Continuity

First, we have to make sure that multi-branchable is selected and then we have to go in EDIT>SEARCH>ADVANCED>ELECTRICAL WORKBENCH>TYPE-BUNDLE SEGMENT>ATTRIBUTE-FULLY CONNECTED

Selecting the "TRUE" option will show all the connected bundle segments while the selecting "FALSE" will show all the non-connected bundle segments.

For now, we will select "FALSE" and search for results. All the bundle segments are highlighted and found showing that all the bundle segments are electrically connected.

Creating flat-pattern of wiring harness bundle

• To make a flattened view of any wiring harness we should be working in the Electrical Harness Flattening workbench of CATIA V5. We should also make sure that the flattening file is saved in the same folder where we have all the parts of the harness assembly.

• Defining the Harness Flattening parameter. Make sure to use the "Single Line" for the Bundle segment and "Double Line" for Protective covering.

At this stage, for clarity, the flattening diagram of the plastic guiding channels has been hidden from the drawing view. The drawings for the guiding channel will be provided separately from the flattening diagram of the harness bundle assembly. The drawings posted above in "STEP-6" have to be used with the wiring harness flatten-view drawing.

Rotate the bundle segments connecting to the four cam-shaft connectors by using the "Rotate" feature in the flattening workbench. It should be noted, that we have "XY-Plane" as the flattening plane so we should make sure that we rotate the bundle segment only along the "XY-Plane".

Creating a flatten-drawing view for the wiring harness assembly

Make a new drawing file and define all the necessary drawing parameters. Insert the front-view of the harness assembly into the drawing file. 

Define the drawing properties as shown below. It should be noted that for the "dress-up" settings 3D wireframe is always "ON". If this setting is not selected then the bundle segments will not be visible on the drawing view.

 

CONCLUSION-

From the above project we learnt how to route wire harness on a V16 Engine.We also learnt about different packaging rules that must be kept in mind during wire routing.We also learnt how to flatten the wire and represent it in the drawing sheet.After finalizing the wire routing, we can request the corresponding Engine design team to provide additional holes for the mounting of Fir tree clips. All necessary details like clearance/ clamping selection, harness fixing requirements, harness continuity were provided in order to design the wiring harness.