FINAL PROJECT ONE: V16 ENGINE WIRING HARNESS ROUTING, PACKAGING, FLATTENING AND DRAWING

OBJECTIVE STATEMENT:

The primary objective of this assignment is to design and route a comprehensive wiring harness for a given engine using CATIA V5 software. The design process will encompass applying industry-standard packaging rules, best practices, and guidelines acquired through the coursework. Particular emphasis will be placed on incorporating appropriate protection coverings to ensure the longevity and functionality of the harness assembly.

 

Furthermore, the assignment necessitates the preparation of a detailed flattened view drawing, showcasing the intricate routing and layout of the wiring harness. Connector data from reputable sources, such as www.te.com, will be utilized to ensure accurate and compatible interface design.

 

Upon completion of the design phase, a comprehensive report will be generated, encompassing critical aspects such as clearance analysis, clipping/clamping selection, harness fixing requirements, harness continuity, and any assumptions made during the design process. The report, accompanied by the CATIA 3D data, will comprehensively document the design process and final product.

 

BUGATTI W16 ENGINE: 

The Bugatti W16 engine we're referring to is the iconic 8.0-litre quad-turbocharged unit that powered the Bugatti Veyron and its special editions from 2005 to 2015. As a wiring harness engineer, there are several key aspects of this engine we'd need to be aware of:

 

Specifications:

1. 8.0L W16 configuration (four banks of four cylinders each)
2. Quad-turbocharged
3. Displacement: 7,993 cc
4. Bore x Stroke: 86 x 86 mm
5. Compression ratio: 9.0:1
6. Fuel system: Direct gasoline injection (up to 15,800 psi)
7. Dry sump lubrication system

 

Power Output:

1. 1,001 metric hp (987 bhp) @ 6,000 rpm
2. 1,250 Nm (922 lb-ft) of torque @ 2,200-5,500 rpm

 

Thermal Management:

1. Highly complex cooling system with 10 radiators (engine coolant, air/air intercoolers, hydraulics, transmission oil)
2. The engine coolant system uses two water pumps and a proprietary coolant rated up to 385°F
3. Cylinder heads and dry sump utilize separate cooling circuits
4. Intercoolers sprayed with water mist for maximum heat dissipation

 

Wiring Harness Considerations:

1. Immense wiring complexity for all engine sensors/actuators
2. Dedicated engine control units and distributed electronic control systems
3. Substantial shielding/grounding required for electromagnetic compatibility
4. Harness routing to minimize exposure to extreme heat/vibration
5. Connectors rated for underhood environments, sealed against moisture/debris

 

Overall, packaging the Veyron's W16 required incredibly intricate engineering on all fronts, including the wiring harness design which had to reliably integrate hundreds of electrics while withstanding the punishing thermal loads and vibrations inherent to this ultra-high performance application. Meticulous design validation would have been critical.

 

STP FILE THAT WE IMPORTED INTO CATIA V5:

 

 

WHY WIRING HARNESSES ARE ESSENTIAL IN MODERN VEHICLES:

Modern automobiles are complex machines brimming with electronic components. Gone are the days of simple electrical systems with just a few lights and a starter motor. Today's vehicles rely on a network of wires, connectors, and protective elements bundled together – the wiring harness – to perform a multitude of critical functions:

Power Delivery: The harness carries electrical current from the battery to power various components like lights, sensors, actuators, entertainment systems, and engine control units.

Signal Transmission: It acts as a communication channel, transmitting low-voltage signals between sensors, control units, and other electronic modules. This allows for functionalities like engine management, airbag deployment, and anti-lock braking systems (ABS).

Data Transfer: With increasing vehicle automation, wiring harnesses facilitate the transfer of data between different ECUs (Electronic Control Units) enabling features like navigation, driver assistance systems, and vehicle diagnostics.

In essence, the wiring harness is the nervous system of a modern car, ensuring proper communication and power distribution for all electrical and electronic functions. Without it, a car would be nothing more than a hunk of metal.

 

FACTORS TO CONSIDER WHEN DESIGNING AN ENGINE WIRING HARNESS:

Here are some key factors an engineer must consider while designing an engine wiring harness:

Performance and Efficiency: The harness needs to be designed to minimize voltage drops and ensure efficient power delivery to all engine components. Wire gauge selection and proper routing are crucial for this.

Heat Resistance: Engine compartments generate significant heat. The wiring harness materials, including wires, insulation, and connectors, must be able to withstand these high temperatures for extended periods without melting or degrading.

Durability and Reliability: The engine environment can be harsh with vibrations, moisture, and potential exposure to chemicals. The harness design should prioritize robust construction and high-quality materials to ensure long-term reliability.

Packaging and Clearance: Modern engines are compact, leaving limited space for the wiring harness. Careful planning is required to route the harness efficiently, avoiding interference with other components and maintaining proper clearance for heat dissipation and ease of service.

Safety: Wiring integrity is paramount for safety. The harness design should minimize the risk of chafing, short circuits, or damage that could lead to electrical malfunctions or fires. Fuse placement and proper grounding are important safety considerations.

Electromagnetic Interference (EMI): Ignition systems and high-voltage components can generate EMI. The harness design might require shielding techniques or separation strategies to prevent interference with sensitive electronic modules in the engine compartment.

Maintainability and Serviceability: In the event of a fault, the harness should be designed for ease of diagnosis and repair. Using quick-disconnect connectors, colour-coded wires, and proper labelling can significantly improve serviceability.

Cost and Weight: While functionality is paramount, balancing cost and weight is crucial. Wire gauge selection and harness layout optimization can help achieve a balance between performance and cost-effectiveness without unnecessary weight gain.

Compliance with Regulations: The wiring harness design needs to adhere to relevant industry standards and automotive safety regulations.

By carefully considering these factors, a wiring harness engineer can design a reliable, efficient, and safe wiring harness that meets the specific demands of the engine and the overall vehicle.

 

ESSENTIAL WIRING HARNESS CONNECTIONS FOR OUR BUGATTI W16 ENGINE:

Here's a breakdown explaining why each connection and component is crucial for the Bugatti W16 engine's wiring harness:

1. Connectors for Fuel Injectors:

Importance: Fuel injectors require precise and reliable electrical connections to ensure accurate fuel delivery and combustion timing for each cylinder.

Rationale: With 16 cylinders, the W16 engine has 16 fuel injectors, and each injector requires a dedicated connector to establish a secure electrical connection.

2. Camshaft Sensors (4 Sensors):

Importance: Camshaft sensors provide crucial information about the position and timing of the camshafts, which is essential for the engine control unit (ECU) to manage the engine's operation.

Rationale: The W16 engine has four banks of cylinders, each with its camshaft, necessitating four camshaft sensors for accurate timing and control.

3. Engine Coolant Sensor:

Importance: Monitoring the engine coolant temperature is crucial for proper thermal management and preventing overheating.

Rationale: The W16 engine's complex cooling system requires a centrally located coolant sensor to accurately measure the temperature between the two cylinder blocks.

4. Engine Oil Temperature and Pressure Sensors:

Importance: Oil temperature and pressure sensors provide vital information about the lubrication system's condition, which is critical for protecting the engine's internal components.

Rationale: Due to the W16 engine's dual-cylinder block design, separate oil temperature and pressure sensors are required for each block to ensure accurate monitoring and control.

5. Transmission Sensors:

Importance: Sensors for detecting the neutral position and vehicle speed are essential for the seamless integration and operation of the transmission system.

Rationale: These sensors provide critical inputs to the engine control system, enabling precise management of the transmission's behaviour and the vehicle's overall performance.

6. Engine-to-Vehicle Harness Interconnection:

Importance: A dedicated interconnection connector facilitates the communication and power transfer between the engine wiring harness and the vehicle's larger wiring harness system.

Rationale: This interconnection ensures seamless integration of the engine's electrical systems with the rest of the vehicle's components and control modules.

7. Harness Mounting and Routing Management:

Importance: Proper mounting and routing of the wiring harness are crucial for ensuring its protection, accessibility, and manufacturability.

Rationale: The complex and dense packaging of the W16 engine requires careful planning of harness mounting points, routing paths, and clearances to avoid interference with other components and facilitate assembly and maintenance.

8. P-Clamps and Mounting Clips:

Importance: These hardware components secure the wiring harness in place, provide proper clearances, and prevent chafing or damage.

Rationale: The vibration and movement within the engine compartment necessitate the use of robust clamping and mounting solutions to ensure the harness remains securely positioned.

9. Guiding Channels and Corrugated Tubes:

Importance: Guiding channels and corrugated tubes protect the wiring harness from extreme temperatures, hazardous liquids, and abrasion.

Rationale: The harsh environment of the engine compartment, with high temperatures and potential exposure to fluids, requires specialized protective measures to maintain the integrity of the wiring harness.

By carefully implementing these steps and considering the specific requirements of the Bugatti W16 engine, wiring harness design engineers can create a robust, reliable, and optimized wiring harness system that ensures the engine's seamless operation and integration with the vehicle's overall electrical architecture.

 

 

DESIGN CRITERIA FOR WIRING HARNESS:

The wiring harness should be routed in a manner that adheres to the following guidelines:

1. Ease of assembly on the vehicle and accessibility for service or failure analysis.

2. Proper securement to prevent damage from interaction with surrounding components.

3. Avoidance of heat zones such as engine exhaust, mufflers, and turbochargers.

4. Protection from direct water splashes and high-pressure fluid lines.

5. Avoidance of sharp environments, including sheet metal bracket edges, corners, and panel edges.

6. Prevention of damage caused by human or machine interaction.

7. Placement away from the driver or passenger reach zone.

8. Consideration of the vehicle's dynamic conditions to prevent harness damage.

9. Routing away from the tyre envelope.

10. Concealment of the harness inside the vehicle, ensuring it is not visible or exposed.

 

PACKAGING RULES:

1. Routing should facilitate ease in manufacturing, accessibility, removal, and maintenance of attached equipment and wiring harnesses.

2. Avoid routing through small structural holes and openings to minimize chafing and handling during installation.

3. Avoid routing and clipping in the blind zone of the operator during harness assembly or service.

4. Protect against potential damage caused by common misuses, such as being handheld or used as temporary support for test equipment.

5. Allow additional slack in the harness according to the surroundings and bending requirements.

6. Ensure routing meets clearance requirements with different surrounding parts.

7. Provide sufficient slack for each branch to avoid additional stress on the wire and terminal crimping joint, while preventing harness fouling due to extra slack.

8. Avoid routing over bolts or near bolted joints to prevent harness damage or puncture. Keep harnesses away from panel mounting screws.

9. Provide protection when routing near sharp edges is unavoidable.

10. Maintain a maximum distance of 200mm between two clips on a straight branch.

11. Use clips and clamps if the harness bends at multiple locations.

12. Minimize the use of sheet-metal brackets.

13. Ensure branch lengths are greater than 50mm.

14. Maintain a minimum distance of 25mm between the clip and the branching point.

15. Keep a minimum distance of 50mm between two branch breakouts.

16. Use rubber grommets when the harness passes through sheet metal panels.

17. Position harness connectors higher than the routing and branching points to prevent water entry due to gravity.

 

ESSENTIAL ASSUMPTIONS:

1. Provide clips/clamps as required and use additional clips/clamps to avoid falling cases.

2. Allow 5-10% slack if needed.

3. Avoid routing over bolts and bolted joints to prevent harness puncture.

4. Provide protection when routing on sharp edges.

5. Adhere to clearance distances and keep the harness away from heat-generating components.

6. Protect according to the surrounding temperature.

7. Avoid direct support for harnesses on fuel lines routed in the engine.

8. Use plastic guiding channels if necessary.

9. Maintain branch lengths greater than 50mm.

10. Keep a minimum distance of 50mm between two branch points and 25mm between the clip and the branch point.

11. Minimize the use of sheet metal brackets on the engine, utilizing available threaded bosses or requesting them.

12. Ensure the wiring harness is easy to assemble and access.

13. When using dummy connectors, ensure that the defined positions are practical, and bundle diameters and placements are properly defined for wire harness routing.

14. Consider creating a harness channel for routing and protection in tight packaging areas with numerous constraints.

 

CONNECTORS, CLIPS AND CLAMPS USED IN OUR LAYOUT:

1. INTERCONNECTION CONNECTOR(776438-4 12-POLE) MOUNTED ON FIR TREE CLIP:

 

2. INJECTOR & CAMSHAFT CONNECTOR(1563689-1 4-POLE):

 

3. SENSOR TO MEASURE THE VEHICLE SPEED & TRANSMISSION'S NEUTRAL POSITION:

 

4. ENGINE COOLANT TEMPERATURE SENSOR:

 

5. TYPES OF FIR TREE CLIPS USED:

 

 

6. P-CLAMP:

 

7. GUIDING CHANNEL:

 

Selecting the right Supporting Features for Automotive Wiring Harnesses:

1. Fir Tree Clips:

A) Closed-Loop Clips:

Function: These clips have a fully enclosed loop design, providing a very secure hold on the harness. They are ideal for areas with high vibration or where the harness needs to be firmly anchored.

Applications: Suitable for critical locations like engine compartments, near suspension components, or areas with significant movement.

B) Omega Clips:

Function: These clips resemble the Greek letter omega (Ω) with a wider opening at the base. They offer a slightly less secure hold compared to closed-loop clips but are easier to install and remove.

Applications: Well-suited for areas with moderate vibration or easier access for service and maintenance. They can be used for routing harnesses along body panels or under the car.

 

2. P-Clamps:

A) Single-Hole P-Clamps:

Function: These P-clamps have a single mounting hole for attaching with a screw or rivet. They offer a simple and cost-effective solution for securing harnesses.

Applications: Suitable for general-purpose routing and securing harnesses to firewalls, body panels, or other flat surfaces.

B) Double-Hole P-Clamps:

Function: These clamps have two mounting holes, allowing for increased stability and the ability to manage slightly larger harness diameters.

Applications: Ideal for situations requiring additional holding power, such as securing harnesses near suspension components or areas with potential twisting forces.

 

3. Cable Ties:

Single-Headed Cable Ties:

Function: Standard cable ties with a one-way locking mechanism for basic bundling of wires. They are simple to use and inexpensive.

Applications: Suitable for organizing and grouping wires within the harness, especially for smaller groups.

Double-Headed Cable Ties:

Function: These ties have a locking mechanism on both ends, allowing for attachment to another cable tie or a mounting point. They offer increased versatility for bundling and securing the harness.

Applications: Useful for bundling multiple harnesses together, securing the harness to a bracket, or creating loops in the harness for strain relief.

 

4. Offset Clips:

Function: Offset clips resemble a single-hole P-clamp but with an angled base. This angled design allows the harness to be routed at a specific angle relative to the mounting surface.

Applications: Ideal for situations where the harness needs to be routed around corners, follow contours of body panels, or maintain a specific clearance from other components.

 

5. Separator clamps:

 

Function: Separator clamps are typically machined from lightweight materials like aluminium. They feature two or more compartments or channels designed to hold individual wiring harnesses. The clamps secure the harnesses together, preventing them from tangling, rubbing against each other, or interfering with other components.

Applications: Separator clamps are commonly used in areas where multiple wiring harnesses converge, such as:

1. Engine compartments
2. Firewall areas
3. Behind the dashboard
4. Underneath the car (for routing harnesses to different vehicle sections)

 

Additional Supporting Features:

• Spiral Wraps: Provide a lightweight layer of protection against abrasion and dust.
• Wire Ducting: Offers more robust protection against abrasion, moisture, and chemicals compared to spiral wraps. Available in corrugated tubes and split loom conduits.
• Grommets: Reduce friction and protect the harness from chafing when passing through sheet metal panels. They can also help prevent moisture ingress and dampen noise.
• Adhesive Mounts: Used for temporary or low-stress applications where the harness needs to be secured to a surface without drilling holes.
• Heat Shields: Made from reflective materials to protect the harness from exposure to excessive heat sources like exhaust manifolds.

 

Guiding Channels in Automotive Wiring Harnesses: Balancing Protection and Efficiency

Guiding channels are specifically designed components used in automotive wiring harnesses to offer targeted protection and manage routing within the vehicle.

Here's a detailed explanation of their importance and when their use might be  avoided, if possible:

Importance of Guiding Channels:

Thermal Protection: Engine compartments generate significant heat. Guiding channels, often made from heat-resistant materials like nylon or fibreglass, shield the wiring harness from exposure to extreme temperatures. This protects the wires and insulation from degradation, ensuring long-term reliability and preventing potential electrical malfunctions due to heat damage.

Abrasion Protection: Guiding channels can provide a physical barrier between the harness and surrounding components that could cause chafing or wear. This is especially crucial in areas with movement, vibration, or sharp edges.

Organized Routing: Guiding channels can assist in maintaining a clean and organized routing path for the wiring harness within the tight confines of the engine compartment. They can also help separate the harness from other components, preventing interference and facilitating easier assembly and servicing.

Strain Relief: In some cases, guiding channels can offer a degree of strain relief on the harness, reducing stress on wires and connectors at connection points.

 

When to Avoid Guiding Channels (if possible):

Cost and Weight: Guiding channels add some cost and weight to the overall wiring harness design. If adequate protection can be achieved through other means like strategic routing, heat shields, or robust wire insulation, then avoiding guiding channels can offer cost and weight savings.

Complexity and Assembly Time: Adding guiding channels introduces additional components that need to be designed, manufactured, and assembled. In situations where space constraints are not severe and alternative protection methods are feasible, simplifying the design by omitting guiding channels can reduce assembly complexity and time.

Limited Space Availability: In extremely tight spaces, guiding channels might not be physically accommodated within the available packaging envelope. In such cases, alternative approaches like using high-temperature insulation or carefully planned routing become necessary.

 

The Decision-Making Process:

The decision to use guiding channels hinges on a careful analysis of several factors:

The severity of the environment: High temperatures, potential for abrasion, or exposure to harsh chemicals would necessitate the use of guiding channels for optimal protection.

Alternative protection methods: If sufficient protection can be achieved through alternative strategies like heat shields, robust insulation, or strategic routing, guiding channels might not be essential.

Packaging constraints: Limited space availability might necessitate exploring alternative methods to accommodate the wiring harness without adding the bulk of guiding channels.

By carefully considering these factors, automotive wiring harness engineers can determine the optimal approach, balancing the need for protection with cost-effectiveness, ease of assembly, and space limitations.

 

Conclusion:

Guiding channels offer a valuable tool for protecting and managing automotive wiring harnesses in challenging environments. However, their use isn't always necessary, and alternative methods should be explored when possible to optimize cost, weight, and assembly efficiency. The key lies in striking the right balance between protection, functionality, and cost-effectiveness for a reliable and well-designed wiring harness.

 

 

WIRING HARNESS ROUTING, PACKAGING AND FLATTENING PROCESS FOR OUR ENGINE:

First, we'll import the STP file that was provided to us into the CATIA environment and save it as a part file.  

 

Next, we're going to create the context assembly as it serves as a central repository for the engine wiring harness design, encompassing three distinct sub-assemblies.

WHAT IS A CONTEXT ASSEMBLY?

A context assembly is a top-level product file within the CATIA V5 environment. It serves as the central container for all the components that constitute the wiring harness.

It typically encompasses three main sub-assemblies:

Geometrical Bundle (or Assembly): This sub-assembly defines the physical layout of the wiring harness within the vehicle. It includes the actual routing of the wires, connectors, clips, clamps, and other supporting features.

Electrical Bundle: This sub-assembly contains all the electrical data associated with the harness. This includes information on wire gauge, colour coding, pin assignments, and connector specifications.

Annotations: This sub-assembly holds any notes, comments, or additional information relevant to the wiring harness design.

 

WHY IS THE CONTEXT ASSEMBLY IMPORTANT?

Centralized Management: The context assembly provides a single, unified location for managing all aspects of the wiring harness design. This allows for efficient organization, version control, and collaboration among engineers working on the project.

Visualization and Packaging Analysis: By incorporating the geometrical bundle within the context assembly, engineers can visualize the complete routing of the harness within the 3D model of the vehicle. This allows for early identification of potential packaging issues, such as interference with other components or insufficient space for proper routing.

Design Verification and Validation: The context assembly facilitates the verification and validation of the wiring harness design. With all the electrical data and annotations readily accessible within the same file, engineers can ensure the design meets all functional and electrical requirements.

Manufacturing and Assembly Support: The context assembly can be used to generate manufacturing documentation, including flat-pattern drawings and bills of materials (BOMs). This information is crucial for efficient harness fabrication and assembly.

 

Issues Without Using a Context Assembly:

Data Fragmentation: Without a central location, electrical data, routing information, and annotations could be scattered across multiple files, leading to confusion, version control issues, and potential inconsistencies.

Packaging Challenges: The inability to visualize the complete harness layout within the vehicle could result in significant packaging problems later in the design process. Clashes with other components or insufficient space allocation for the harness might require costly redesigns.

Design Errors and Omissions: The lack of a centralized location for design verification could lead to undetected errors or omissions in the electrical data or routing configuration. These issues might not be discovered until later stages of development, causing delays and rework.

Manufacturing Difficulties: Generating accurate manufacturing documentation becomes challenging without the centralized data organization provided by a context assembly. Incomplete or inaccurate BOMs and drawings can lead to production delays and potential quality issues.

 

CONCLUSION:

Context assembly is a vital element in CATIA V5 for designing effective and well-packaged automotive wiring harnesses. By providing a centralized platform for managing all aspects of the design, it streamlines collaboration, facilitates verification, and helps avoid costly errors down the line.  Using a context assembly ensures a more efficient, reliable, and well-coordinated wiring harness design process.

 

Next, In CATIA, we will initiate the design process by establishing a new product. This product will function as the context assembly and serve as the central hub for managing all data about the engine wiring harness.

Engine Model Incorporation: Subsequently, we will import the existing part file of the engine into the newly created context assembly. This establishes a reference for the engine geometry within the design environment.

Dedicated Harness Assembly: Next, we will create an additional product within CATIA. This product will be specifically designated for the wiring harness assembly. Naming the product appropriately, for example, "Engine Wiring Harness", will enhance clarity and organization.

Component Import and Routing: All necessary components, including:

• Connectors
• Mounting equipment
• Supports
• Any other relevant elements

These components will be imported into the dedicated wiring harness assembly product. Within this dedicated product, the essential tasks of:

1. Wiring harness routing: Defining the physical path of the wires within the engine compartment.
2. Packaging operations: Ensuring optimal placement of the harness components to avoid interference with surrounding parts and achieve efficient space utilization, will be undertaken.

 

Independent Design: It's crucial to emphasize that the wiring harness assembly will be designed entirely independently. This means:

No direct reference will be taken from the engine model geometry.

The harness will be designed as a self-contained assembly, ensuring it functions independently within the engine compartment.

By adhering to these steps, we establish a well-structured and organized approach for designing the engine wiring harness in CATIA V5. This approach fosters clarity, and efficient data management, and minimizes the risk of errors during the design process.

 

Before integrating these electrical components into our CATIA environment, we'll assess their placement and determine the appropriate locations for each component.

1- Engine Coolant Sensor

2. Transmission's Neutral Position Sensor

3. Vehicle Speed Sensor

 

We'll access the dedicated wiring harness product by double-clicking it. Then, using a right-click, we'll open it in a separate CATIA window for focused routing and packaging.

 

Next, following the predefined locations, we will import and position all necessary electrical components within the dedicated wiring harness product.

Imported and positioned four camshaft connectors at desired locations as shown in the above image.

1- Coolant Temperature Sensor

2- Vehicle Speed Sensor

3- Transmission's Neutral Position Sensor

4 & 5- Positioned P-Clamps  

 

 

 

The required guiding channels and L-shaped clip for mounting the interconnection connector have been incorporated into the context assembly. These components are mechanical and will not be electrically defined within the wiring harness product file.

 

 

All requisite pre-defined electrical components have been imported and placed within the design environment. We will now proceed with the creation of organized wire bundles using the 'Electrical Harness Assembly' workbench.

 

Now, we're going to activate the product file named 'Wiring Harness Routing & Packaging' and start routing these components together as shown below:

All of these harness bundles are 5mm in diameter.

 

Protective coverings will be applied to designated segments of the wiring harness bundles. These coverings, specifically 5mm inner diameter and 6.5mm outer diameter corrugated tubes, will exclude the fuel injector connectors. The guiding channels, with their top sections covered, will provide sufficient protection for these connectors.

 

The next step involves transitioning the complete wiring harness assembly into a two-dimensional representation. This will be achieved within the 'Electrical Harness Flattening' workbench by defining a set of parameters to govern the flattening process.

Then, we're going to use the 'Extract' option present under the 'Flatten' Toolbar. 

The flattening process will be guided by the selection of a target plane within the design environment. Subsequently, a single, representative bundle segment will be chosen. Utilizing the 'Select All Branches' function, all electrically continuous segments within the harness will be automatically identified and included in the flattening operation.

 

The flattened wiring harness assembly will be documented in a drawing utilizing the A0 ISO paper size (1189mm x 841mm) in landscape orientation. A first-angle standard projection will be employed to ensure a clear and consistent representation of the assembly.

 

 

Drawing for our Flattened Wiring Harness Assembly:

Selection of Front View and 3D Wireframe Representation:

The drawing will utilize a single "Front View" of the flattened wiring harness assembly. This is because a flattened representation eliminates the need for additional views, as all elements are now displayed in a single plane. To ensure clarity of the harness layout, the "3D Wireframe" representation will be chosen. This displays the individual wires within each bundle, providing a more detailed view compared to a simple line representation. Additionally, the "Always Visible" setting will be enabled for the wireframe, guaranteeing their consistent display throughout the drawing.

 

Frame and Title Block:

Following the selection of the front view, the drawing will be enhanced by accessing the "Edit" menu and selecting "Sheet Background" This allows for the insertion of a frame and title block template. The frame provides a visual border for the drawing, while the title block serves a critical purpose:

 

Title Block: This crucial element contains essential project information such as the drawing title, part number, revision number, and scale. It also includes designated areas for the engineer's signature and approval date. The title block streamlines communication and ensures clarity for anyone referencing the drawing – from engineers and designers to the purchasing team and manufacturing personnel.

 

Bill of Materials (BoM):

Finally, the project will be completed by incorporating a Bill of Materials (BoM) within the drawing. The BoM is a tabulated list that specifies all the components required to assemble the wiring harness. It typically includes:

 

Part Number: Unique identifier for each component.

Description: Detailed description of the component (e.g., wire size, colour, length).

Quantity: Number of each component required.

 

Importance of BoM:

The BoM serves as a vital resource for various teams involved in the project:

Engineers: Reference the BoM to ensure all necessary components are included in the design.

Purchasing Team: Utilize the BoM to accurately order the required materials and quantities.

Manufacturing Personnel: Rely on the BoM during assembly to verify they have the correct components readily available.

Inventory Management: The BoM provides a clear picture of component usage, aiding in inventory control and forecasting future needs.

By incorporating a comprehensive BoM, the drawing becomes a self-contained document that effectively communicates the assembly requirements to all stakeholders involved in the project.

Finally, we'll convert our Context Assembly's CATproduct file into a CATpart file from the 'Tools' option as shown below:

We'll save that CATpart as an IGS file as well.

Engineers convert their CAD (Computer-Aided Design) product files into different file formats for several reasons:

Data Exchange and Compatibility: Different CAD software packages may use proprietary file formats that are not compatible with one another. By converting the files to a neutral format like IGES (Initial Graphics Exchange Specification) or STEP (Standard for the Exchange of Product Model Data), engineers can share and exchange design data with other systems, suppliers, or manufacturers that may be using different CAD software.

Manufacturing Compatibility: Many computer-aided manufacturing (CAM) systems and computer numerical control (CNC) machines require specific file formats for processing and manufacturing the design. Converting the CAD model to a format like IGES or STL (STereoLithography) allows these manufacturing systems to read and interpret the design data correctly.

Simplification and Data Reduction: CAD product files often contain a lot of additional information, such as assembly constraints, meta-data, and other non-geometric data that may not be necessary for certain downstream processes. Converting the product file to a part file or neutral format like IGES can help strip away unnecessary data, simplifying the file and reducing its size for easier handling and processing.

Legacy System Compatibility: Some older manufacturing systems or CNC machines may only support specific file formats like IGES, which was one of the earliest neutral CAD data exchange formats. Converting modern CAD files to IGES ensures compatibility with these legacy systems.

Intellectual Property Protection: In some cases, engineers may convert their CAD files to a neutral format like IGES or STEP to protect their intellectual property when sharing designs with external parties. These neutral formats can exclude proprietary features or design details that the engineer wants to keep confidential.

By converting their CAD product files to part files or neutral formats like IGES, engineers ensure that their designs can be seamlessly shared, processed, and manufactured by various systems and stakeholders involved in the product development and manufacturing process.