Objective

• To learn ideology used in surface modeling of components.
• To learn surface modeling methods.

Introduction

Solidworks is a multi-platform Computer-aided design (CAD) and Computer-aided engineering (CAM) software developed by a French Company Dassault Systemes.

Solidworks CAD modeling software is used in the following industries: Aerospace & Defense, Architecture, Engineering and Construction, Consumer goods - distribution, FMCG - Distribution, Energy, and processes, Finance and Corporate Services, High Technology, Industrial Equipment, Life Sciences, Marine & Offshore, Natural Resources, and Transport & mobility.

Solidworks enables the creation of 3D parts from 2D sketches, surfacing, sheet metal, weldments, molded tooling parts up to the definition of mechanical assemblies.

Some of the popular features of 3D part modeling are discussed below.

Sketcher (Sketch): Sketcher workbench is the most commonly used workbench to draw various types of profiles for different purposes. It consists of line, circle, spline, rectangle, ellipse, hexagon, etc. tools. It also consists of extend, trim, convert entities, offset entities, mirror, patterns, and 3D sketch features.

Features: This workbench is mainly used for producing solid parts from existing sketches. Extruded boss/cut, revolved boss/cut, swept boss/cut, lofted boss/cut, chamfer, fillet, mirror, shell, draft, rib, etc. tools will be seen in this workbench.

Surfacing: Very complex surfaces can be modeled in Solidworks. Popularly its surfacing workbench is used to design surfaces. In this workbench, you can see extruded, revolved, swept, lofted, boundary, filled, offset, etc. surfaces tools.

In this project, we will be using the concepts and terminology used while modeling. It will familiarize us with the commonly used functions in Solidworks.

Our aim is to do the surface modeling of the car. Hence, we will be using surfacing workbench for creation of the surfaces most of the time. And for parts like rims, tires and brake calipers we will be using solid modeling workbench.

The need for Surface Modeling

The product and industrial designers these days are giving importance to product styling and providing a unique shape to components.

Generally, this is done to make sure that the product looks attractive and presentable to the customer.

The shape of products are managed using surface modeling techniques. Surface models are three-dimensional models with no thickness and unlike solid models, they do not have mass properties.

Solidworks provides a number of surface modeling tools to create complex three-dimensional surface models.

Design Approach

For the surface modeling of the car, it is a tedious task to create the perfect geometry of the car. Hence, to ease the things we decided to build basic profiles of the car first and then separate each part from the main body. After separating the individual part, we will be modifying them as per our requirement and assemble them in an assembly file later.

The steps followed during the modeling are shown in the chart below.

Timeline

The linear graph shows the timeline of the work hours required to build the surfaces per week. Weeks shown here are as per weekly challenges. Please note that we have excluded hours taken to solve the problems occurred during the surface modeling stage.

Creation of Basic Profiles

Blueprints are one of the most useful things for modeling a car using any 3D software.

They are basically orthogonal drawings of the car in every direction (front, top, side, and rear). They allow us to draw curves over a picture so that we can be precise and match the real shape of the car.

Modeling of a car is a big task and is done by step by step surface modeling of different surfaces.

The car has a symmetric shape, and hence we will be modeling half of the car only and then mirror the body. It will reduce our lot of time. As said earlier, first we have built basic profiles of the car and later on created separate parts for our ease.

When modeling a car, the roof is often taken as a starting point, as its construction is quite easy and uses curves spanning the entire model. Hence, we started modeling of the roof first.

For modeling roof, projected curves are used to create precise 3D profiles for further surface creation using Surface Boundary tool.

For creation of projected curves we need to create sketches first. These sketches were made with the use of splines with their proper dimensioning.

The profiles of side, fenders, door, rear, front bumper, hood, windows are made with the help of various tools listed below.

• Boundary Surface
• Filled Surface
• Extruded Surface
• Offset Surface
• Ruled Surface
• Fillet
• Delete Face
• Extend Surface
• Trim Surface
• Knit Surface

Boundary Surface

The boundary surface feature lets you create surfaces that can be tangent or curvature continuous in both directions (all sides of the surface). When high-quality surfaces with curvature continuity are required Boundary Surface tool is used.

A boundary surface uses curves that fully enclose a single shape: say a rectangle. You can either use a single sketch or a combination of multiple sketches to describe a closed boundary.

Filled Surface

The Filled Surface feature constructs a surface patch with any number of sides, within a boundary defined by existing model edges, sketches, or curves, including composite curves.

Extruded Surface

The Extruded Surface feature lets you to extrude the surface from the sketch profile of the surface.

Offset Surface

The offset surface feature creates a surface from the existing surface. You can create an offset surface with a distance of zero.

Ruled Surface

The Ruled Surface command creates surfaces that extend out in a specified direction from selected edges.

Examples of how you can use ruled surfaces:

• Add tangent extensions to complex surfaces
• Create drafted sidewalls
• Replace non-drafted surfaces on imported models with drafted surfaces (using the Tapered or Sweep type)
• Create parting and interlock surfaces.

Fillet

A fillet is a tool that enables you to smooth the edge between two adjacent faces in a surface body that meets at an angle.

There are four types of fillet i.e. constant type fillet, variable size fillet, face fillet, and full round fillet.

Delete Face

With Delete Face tool, you can do the following:

• Delete a face from a surface body, or delete one or more faces from a solid body to create surfaces.
• Delete a face from a surface body or solid body and automatically patch and trim the body.
• Delete face and generate a single face to close any gap.

Extend Surface

Extend a Surface is a tool using which you can extend a surface by selecting an edge, multiple edges, or a face.

Trim Surface

The trim Surface tool is used to trim the intersecting surfaces. You can use a surface, plane, or sketch as a trim tool to trim intersecting surfaces. You can also use a surface in conjunction with additional surfaces, as mutual trim tools.

In the PropertyManager, under Trim Type, there are two types available, Standard and Mutual.

Standard - Trims surfaces using surfaces, sketch entities, curves, planes, and so on.

Mutual - Trims multiples surfaces using the surfaces themselves.

Knit Surface

The Knit Surface tool is used to combine two or more faces and surfaces into one.

Export to new file and refine the design

After the creation of basic profiles of the car, now it was time to separate the surfaces of the different parts from the main body and refine the design of each part.

We could have modeled the entire car and all its details within the same file. However, to ease the process, we divided the car into multiple parts defined in separate files. All the parts of the car were then assembled in a special file called an Assembly.

Different parts were exported to new files and their shapes were refined using surfacing tools to meet the final design expectations.

After finalizing the shapes, the other half portion of the car was created using the mirror tool as discussed earlier.

Windshield

Rear Window

Windows

Doors

Hood

Rear Bumper

Grille

Headlights

Main Body

In the end, the surfaces of the main body were knitted together to form a single surface body. This body was then mirrored with respect to the side plane and knitted to the respective surfaces.

A fuel tank opening is created at last on the rear side of the car as shown.

Solid Modeling

Up to now, we had created the bodies of the car using surface modeling techniques. Now, we needed to model the wheels of the car.

The wheel of the car consists of three parts i.e. rims, tires, and brake calipers. We modeled the rims (front and rear), tires (front and rear) and brake calipers using solid modeling techniques.

The various tools used for modeling wheels are

• Revolved Boss/Base & Cut
• Extruded Boss/Base & Cut
• Surface Loft
• Cut with surface
• Combine
• Swept Cut
• Circular pattern
• Chamfer
• Fillet
• Draft
• Sweep

Revolved Boss/Base & Cut

Revolves add or remove material by revolving one or more profiles around a centerline. You can create revolved boss/bases, revolved cuts, or revolved surfaces. The revolve feature can be a solid, a thin feature, or a surface.

Extruded Boss/Base & Cut

The Extrude Property Manager defines the characteristics of extruded features. You can create solid or thin extruded features.

A cut is a feature that removes material from a part or an assembly.

With multibody parts, you can use cuts to create disjoint parts. You can control which parts to keep and which parts are affected by the cut.

Surface Loft

Loft creates a feature by making transitions between profiles. A loft can be a base, boss, cut, or surface.

You create a loft using two or more profiles. Only the first, last, or first and last profiles can be points. All sketch entities, including guide curves and profiles, can be contained in a single 3D sketch.

Cut with Surface

You can cut a solid model by removing material with a surface or plane. With multibody parts, you can select which bodies to keep.

Combine

In a multibody part, you can combine multiple solid bodies to create a single-bodied part or another multibody part.

You can add or subtract bodies, or keep material that is common to the selected bodies.

Circular Pattern

The Circular Pattern Property Manager appears when you pattern one or more features around an axis.

Chamfer

The chamfer tool creates a beveled feature on selected edges, faces, or a vertex.

Fillet

Fillet/Round creates a rounded internal or external face on the part. You can fillet all edges of a face, selected sets of faces, selected edges, or edge loops.

There are different types of fillets such as constant size fillet, multiple radius fillet, round corner fillet, setback fillet, variable size fillet, face fillet, full round fillet, asymmetric fillet.

Draft

Draft tapers faces using a specified angle to selected faces in the model.

Sweep

Sweep creates a base, boss, cut, or surface by moving a profile (section) along a path. A sweep can be simple or complex.

Rims

Tires

Disc

Caliper

Emblem

After creating all parts, now the car needed the emblem. The construction of the emblem only relies on relatively straightforward solid modeling.

The modeling of an emblem was a bit more challenging because of its embossed design.

Extruded Boss/Base, Extruded cut and Flex tools were used in the design of the emblem.

Flex

Flex features deform complex models in an intuitive manner.

You can create four types of flexes:

• Bending
• Twisting
• Tapering
• Stretching

Assembly

Assembly is a file consisting of two or more parts and other assemblies called sub-assemblies.

Adding a component to an assembly creates a link between the assembly and the component. Changes in the component are automatically reflected in the assembly.

Sub-assembly

When an assembly is a component of another assembly, it is referred to as a subassembly. You can nest subassemblies in multiple levels, to reflect the hierarchy of your design.

In this project’s assembly, we have different parts like doors, hood, windows, bumper, etc. and sub-assemblies of front and rear wheels.

All the parts of the car are assembled together with the help of the mate feature.

Mate

Mates create geometric relationships between assembly components.

As you add mates, you define the allowable directions of linear or rotational motion of the components.

You can move a component within its degrees of freedom, visualizing the assembly\'s behavior.

Sub-assembly of Brake Disc

Sub-assembly of Brake Disc consists of a disc and a caliper.

Both the parts are assembled using concentric and centered width mates.

Sub-assembly of Wheel

Sub-assembly of the front wheel and the rear wheel is the same. This sub-assembly consists of rim, tire, and sub-assembly of the brake disc.

All the parts are assembled using concentric, coincident and distance mates.

Assembly of Aston Martin One-77

After completion of all the sub-assemblies, we proceeded to the final assembly of the car.

Final assembly of the Aston Martin One-77 consists of the grille, hood, windshield, windows, doors, rear window, rear bumper, emblem and sub-assemblies of front and rear wheel.

Front View

Top View

Side View

Rear View

Photorealistic renderings

Renderings is the process of creating a 3D model into a realistic image.

The photorealistic renderings can be done in two ways:

• Using PhotoView 360
• Using Solidworks Visualize

For the rendering of Aston Martin car, I have used PhotoView 360.

Two types of color variants are rendered.

Conclusion

We have learned from simple to complex surface modeling methods, creation of surfaces with different approaches to get the expected results.

A new approach to solid modeling using different tools were learned during this project.

The model can further be improved by adding more details to the rear light, adding numbers on the number plate to look it more operational.