Backdoor Wiring Harness and Flattening in CATIA V5

OBJECTIVE

To route the wiring harness on the given Car body (backdoor) along with the necessary protective covering and to prepare a flattened view drawing in CATIA V5.

PROCEDURE

1. The given CAD data is of a backdoor. Before we can route, we have to list all connection points that will house the connectors and thus would require a wiring harness connecting them. Upon close examination we can list the following connectors and supports required:-
   1. 1 connector (12 terminals) for interconnection and a cavity clip.
   2. 2 connectors (2 terminals) for the taillights.
   3. 1 connector (2 terminals) for the wiper motor.
   4. 1 connector (2 terminals) for the door latch sensor.
   5. 2 connectors (1 terminal) for the rear defogger and,
   6. Clips to fix the harness onto the panels.
2. For the next step, we would be required to define all the components we wish to use for the routing as an electrical component. This includes defining the connectors, and the clips electrically.
   1. Defining the Inter-connector
      • First, in the electrical part design workbench, we use the define connector command to define the connector part number and terminal information.
      • Then, we create 3 points viz., the connector connection point, the bundle entry point, and the cavity connection point. We also create the axis system for the connector connection and cavity connection.
      • Finally, we use the define connector connection point command, define bundle entry point command, and define cavity connection point command to fully define the connector electrically.
   2. Defining the cavity clip
      • We first, define the clip as an electrical mounting device.
      • Next, we create the cavity connection point and axis system.
      • Finally, we use the define cavity connection point command to define the cavity clip.
   3. Defining the 2-pin and single-pin connector
      • First, in the electrical part design workbench, we use the define connector command to define the connector part number and terminal information.
      • Next, we create 2 points viz., the connector connection point, and the bundle entry point. We also create the axis system for connector connection.
      • Finally, we use the define connector connection point command and define bundle entry point command to fully define the connector electrically.
   4. Defining the Push-clip
      • We create 2 points at the center of the openings and create 2 planes normal to the base and 3rd plane at the base.
      • Using the define support command, we define the entry, exit, and base planes.
      • We repeat the same for the other entry as well.
      • The push-clip is now fully defined.
3. Now that we have defined all components required for routing, we create an assembly product, name it Assy_Backdoor_Wiring_Harness_Context assembly, and add the backdoor CAD part. We also create the Assy_Backdoor_Wiring_Harness_Geometrical_Bundle assembly which will house the connectors, clips, and the multi-branchable upon routing.
   1. Now, we activate the Geometrical bundle by double-clicking and we insert the Push-clip and all the required connectors. In the assembly workbench, we move each connector and clip to the required position using the move command to fix their final positions.
   2. Next, we move to the electrical harness assembly workbench and define the assembly as a geometrical bundle using the geometrical bundle command. Then we activate the multi-branchable command and create a branch definition to route the harness of the required diameter and slack percentage through the clips joining the inter-connector using the route definition window.
   3. We similarly connect each connector with the harness by creating a branch point and joining it with the same.
   4. After we have connected all the connectors, we check for bundle connectivity by using the search command under the Edit menu.
   5. Once all the branches are connected we use the protective covering command in the harness assembly workbench to add cot tubes of required diameter to the branches with reliefs in the connector ends.
   6. For the final step, we update the context assembly and save the product in the required folder to get the final harness routing.
4. Once the wiring harness routing is done, we flatten it before we can represent it in a drawing. For that, we create a new product file and give the name Assy_Backdoor_Wiring_Harness_Flattening product.
   • Before we could import the geometrical bundle in the flattening assembly, we first had to configure the harness flattening parameters.
   • Once the parameters are saved, the flattening commands are active. We use the extract command to import the geometrical bundle product into the flattening product.
   • Now we use the flatten command and select all branches to flatten the harness bundle in the provided plane.
   • We now align the clamps, supports, and connectors to face their mountings normal to the flattened plane to help understand the connector or clamp type in drawings. We also bend or rotate any branch as per our will to make the harness compact while drawing and presentable.
5. For the final step, we create a new drawing file with the required size and import the front view of the flattened harness, and the front view of all the unique connectors used to provide terminal information. We switch to the sheet background and add a title box and Bill of Materials in the drawing.

HARNESS FLATTENING DRAWING