Modelling and rendering of Audi A7.
TITLE OF THE PROJECT: Final Independent Project - Modelling and rendering of Audi A7.
OBJECTIVE: To model and assemble an Audi A7 using Solidworks and render it using Solidworks Visualize.
INTRODUCTION
Solidworks
It is a solid modelling computer-aided design (CAD) and computer-aided engineering (CAE) computer program that runs primarily on Microsoft Windows. SolidWorks is published by Dassault Systèmes. SolidWorks is a solid modeler, and utilizes a parametric feature-based approach which was initially developed by PTC (Creo/Pro-Engineer) to create models and assemblies. The software is written on Parasolid-kernel.
Building a model in SolidWorks usually starts with a 2D sketch (although 3D sketches are available for power users). The sketch consists of geometry such as points, lines, arcs, conics (except the hyperbola), and splines. Dimensions are added to the sketch to define the size and location of the geometry. Relations are used to define attributes such as tangency, parallelism, perpendicularity, and concentricity.
In an assembly, the analog to sketch relations are mates. Just as sketch relations define conditions such as tangency, parallelism, and concentricity with respect to sketch geometry, assembly mates define equivalent relations with respect to the individual parts or components, allowing the easy construction of assemblies.
Finally, drawings can be created either from parts or assemblies. Views are automatically generated from the solid model, and notes, dimensions and tolerances can then be easily added to the drawing as needed. The drawing module includes most paper sizes and standards.
Solidworks Visualize
It is a suite of standalone software tools that combine industry-leading rendering capabilities with design-oriented features and workflows that enable easy and fast creation of visual content for designers, engineers, marketing, and other content creators. The software is provided in two different versions:
- SOLIDWORKS Visualize Standard
- SOLIDWORKS Visualize Professional
SOLIDWORKS Visualize Professional includes a Virtual Reality (VR) output which renders a user-specified number of images from around the model and stitches them together so the model can be viewed from all angles, creating a truly interactive experience tumbling around the model.
Audi A7
It is an executive car produced by Audi since 2010. A five-door liftback, it features a sloping roofline with a steeply raked rear window and integrated boot lid (forming the so-called "Sportback"), and four frameless doors.
The A7 is in essence, a four-door fastback version of the C7-series Audi A6, based on the Volkswagen Group MLB platform. The A7 was released before the more conventional A6 saloon/estate. Both cars share the same core structure, drivetrain, chassis, dashboard and interior, whilst the A7 has its own unique exterior panelwork. It also differs from the A6 in that it uses aluminium for much of its front body structure. The A7 was also the first fastback to appear within the Audi C-platform series since the Avant version of the C2 Audi 100, which was discontinued in 1982.
There are series of variants in it like Audi A7 Sportback, Audi S7 and Audi RS7. These vary in terms of facelifts, petrol and diesel engine model specifications. The new A7 was launched in India in 2018.
DESIGN METHODOLOGY
The car was modelled using both solid modelling as well as surface modelling. Most of the parts were made by surface modelling. Once after all the parts were modelled separately they were assembled to create the Audi A7. It consists of following parts,
- Disc Brake
- Rim
- Calliper
- Tyre
- Bolt
- Car body
Following are the assemblies created,
- Wheel aseembly
- Car assembly
- Solid Modelling: The 3D part is the basic building block of any large scale design. Features are the individual shapes that, when combined, make up the part. One can also add some types of features to assemblies. Part documents can contain multiple solid bodies that we can manipulate the same way as single solid bodies.
- Surface Modelling: It plays a major role in modelling the car. Most of the parts in the car are surface modelled. Surface modelling is a more complex method for representing objects than wireframe modelling, but not as sophisticated as solid modelling. Surface modelling provides the ability to build out a visual representation of an object’s exterior and its contours.
Design methodology is explained by the flow chart as follows,
BLUEPRINT SETUP
Below is the blueprint used for the rim,
This blueprint was used to create accurate curves for the rim.
Following are the blueprints used to create the car body,
Front
Back
Top
Side (Right)
Isometric view of blueprint setup in Solidworks
First the side blueprint was fixed in the workspace by fixing its starting point at the origin and giving it a desired length, then by taking it as a reference rest of the blueprints were fixed in the environment. The top blueprint was fixed by taking origin as the starting and mid point reference and also the length of the side blueprint was taken as a reference. The front and the back blueprints were fixed with respect to the origin, by taking it as mid point reference and taking the height and width of the side and top blueprint as a reference.
PARTS OF THE CAR
Bolt
Following is the image of a bolt,
Commands used:
- 2D sketch
- Smart Dimensions
- Appearance
- Extruded boss/base
- Surface revolve
- Replace face
- Body-delete/keep
Appearance given: Chromium plate.
Rim
Following is the image of a rim,
Commands used:
- 2D sketch
- Smart Dimensions
- Appearance
- Reference plane
- Sketch picture
- Extruded boss/base
- Surface revolve
- Extruded cut
- Axis
- Circular pattern
- Combine
- Draft
- Fillet
- Surface cut
- Revolved boss/base
- Split line
- Dome
- Surface offset
- Surface extend
- Mirror
- Body-Delete/keep
Appearance given: Chromium plate.
Tyre
Following is the image of a tyre,
Commands used:
- 2D sketch
- Smart Dimensions
- Appearance
- Revolved cut
- Surface revolve
- Reference plane
- Extruded cut
- Circular pattern
- Mirror
Appearance given: Matte rubber
Calliper
Following is the image of a calliper,
Commands used:
- 2D sketch
- Smart Dimensions
- Appearance
- Extruded boss/base
- Dome
- Extruded cut
- Axis
- Mirror
Appearance given: Matte iron
Disc Brake
Following is the image of a disc brake,
Commands used:
- 2D sketch
- Smart Dimensions
- Appearance
- Reference plane
- Extruded boss/base
- Chamfer
- Axis
- Circular pattern
- Extruded cut
- Extruded revolve
Appearance given: Chromium plate
Car body
Car body comprises combination of both solid and surface modelling but mostly it's created using surfacing tools.
Following are the images of the car body in different views,
Front view
Back view
Top view
Right side view
Isometric view
Commands used:
- 2D sketch
- 3D sketch
- Smart Dimensions
- Appearance
- Reference plane
- Sketch picture
- Project curve
- Filled surface
- Boundary surface
- Lofted surface
- Trim surface
- Offset surface
- Extend surface
- Extruded surface
- Knit surface
- Shell
- Dome
- Extruded boss/base
- Split line
- Body-Delete/Keep
- Delete face
- Ruled surface
- Thicken
- Body-Move/Copy
- Surface cut
- Composite curve
- Swept surface
- Chamfer
- Circular pattern
- Extruded cut
- Mirror
Appearance given: Clear glass, area light, chromium plate, metallic cool grey, white, glass fibre, red neon tube and black paint.
ASSEMBLIES
Wheel assembly
Following is the image of the wheel assembly and feautre tree,
Mates:
Rim :- Inplace mate
Tyre :- Inplace mate
Calliper :- Inplace mate
Disc brake :- Inplace mate
Bolt :- Inplace mate.
For the all the parts inplace mate was given as they were built by taking reference of each other, so after inserting them in the assembly environment they got fixed by themselves according to the reference used to build them initially.
In case of bolts, only one bolt was imported and was given inplace mate and the rest of the bolts were circular patterned by taking axis as the reference for five instances for the rotation of 360 degrees.
Car assembly
Since parts of the wheel were modelled separately, the assembly of the wheel was large when compared to the size of the tyres in the blueprints of the car. So, in order to mate wheel with the car body it had to be scaled down to match the size of the tyre in the blueprints of the car.
So to do that wheel assembly was saved as a part first and then it was scaled down about the centre to a factor of 0.16, i.e., size was reduced to the factor 0.16 in comparison to its original size and then it was assembled with the car body.
Images:
Wheel assembly saved as a part
Scaling parameters
Car assembly
Mates: Tyre - Concentric and coincident. The tyre was given concentric and coincident mate with the cylindrical rod in the car which was created as a reference for the wheels to rotate about so that they can have dynamic motion.
Same procedure was followed to fix rest of the tyres with the car body.
PHOTOREALISTIC RENDERS
Following are the rendered images of the car created in Solidworks Visualize,
Modern Garage - Back
High contrast studio
Industrial lot
Racetrack
Modern Garage - Front
CONCLUSION
By doing this project I have learned various new tools and number of new ways to model complex parts in quick and easy way to get the desired results. I have also learned to scale the parts according to the requirement in the assembly rather than creating a whole new part saving large amount of time and effort.
This project has also increased my ability to model complex parts using surface tools in much less time and has also increased my fluidity in both surface and solid modelling.