Aston Martin ONE-77 Challenge-11 (Project)

Aim: To do the Surface modelling of Aston-Martin One-77

Introduction:

The Aston-Martin One-77 is a two-door, two-seater sports car built by the British car manufacturer Aston-Martin. In this project we are going to model the car in SolidWorks 2021(student edition) using the Surfacing and Solid Modelling (Hybrid-Modelling).

 

BASICS OF SURFACING:

Why need Surfacing modelling?

• We can perform most of things done using solid modelling. However, many of these things(part-modelling) are inefficient and may raise difficulties in complex shape modelling.
• The word surfacing has often been used and confused with complex shapes. Not all surface work is done to create complex shapes, and many complex shapes can be made directly from solids.
• Many users think that because they don’t make complex shapes, they never need to use surface features. But mainly examples that don’t require complex shapes, can easily be done using surfacing techniques.

What is Class-A Surface?

• Class A surface refers to those surfaces which are VISIBLE and abide to the physical meaning in a product. They are given to a product for aesthetics (for good looks).
• We can see these types of surfaces in our day-to-day life products such as automobiles and in consumer goods such as toothbrushes, mobile phones, laptops, etc.
• It is a requirement where aesthetics has a significant role. For this reason the exterior of automobiles are referred to as Class-A.
• This term “Class-A Surface” is mostly used in Plastic part designs.

Quality requirements about Class-A surfaces:

• The primary requirements for Class-A are the same as for production quality surfacing in all industries: to build to tight tolerances for G0, G1 and G2 continuity.
• It is important to note that there are no absolute rules for tolerances or continuity levels. It is part of the skill and knowledge of the Class-A modeler to be able to judge which settings will result in the right quality in the production car.
• It is highly required that surfaces created as a Class-A should have Curvature continuity (i.e. the continuity between the surfaces sharing the same boundary).

Surface Continuities and its types:

• The term “Surface continuity” is valid only when there is a connection or contact between 2 surfaces.
• Technically speaking this terminology is used in surface modelling to define the flow of curves/surfaces.
• The types for Surface Continuity are nothing but the way with which the 2 surfaces meet
• We describe the ‘smoothness’ of a junction, where one surface meets another, using the term 'G' (Where G = Geometry)

Types of Surface Continuities:

1. G0 – Position (touching) Continuity:

• If 2 curves are having a common endpoint, with no further condition, are positionally continuous. This is the less smooth type of joint, as the condition to satisfy the common endpoint, no matter what the flow of the 2 curves/surfaces around the joint.

 

2. G1 – Tangent (angle) Continuity:

• We cannot have G1 continuity unless we have at least G0 continuity.
• The best example of G1 continuity is a fillet or a blend with the tangent continuity.

 

3. G2 – Curvature (radius)Continuity:

• Previous 2 conditions are the prerequisites before this G2 continuity can be applied to a pair of curves/surfaces.
• Our curves must now touch, be tangent with each other and have the same curvature, at the point where they touch.
• Technically speaking, this means that our output geometry must now be curved as well.
• Straight lines have no curvature (or infinite curvature) so a pair of inputs containing a straight line cannot meet G2 conditions.

 

4. G3 – Acceleration/Torsion (Rate of change of curvature):

• Previous 3 conditions of continuity are prerequisites before applying this input condition.
• G3 curvature continuity includes the concept of ‘Acceleration’ of curvature e. the amount of change in the curvature, over the length of the curve.

BASICS TOOLS/ENTITIES OF USED IN THIS PROJECT:

Sketch Entities:

Fig. Shows the list of Sketch Entities

Sketch Tools:

• Sketch Fillets
• Sketch Chamfers
• Offset Entities
• Convert Entities
• Intersection Curves
• Face Curves
• Trim Entities
• Extend Entities
• Split Entities
• Jogging Sketch Lines
• Make path
• Construction Geometry
• Mirror Entities
• Dynamic Mirror Entities
• Move, Copy, Rotate, Scale or Stretch Entites
• Align Grid/Origin Property Manager
• Modify Sketch Dialog Box
• Repair Sketch
• Share Sketch
• Closing Sketches to Models
• Sketch Picture
• Sketch Patterns

Sketch Picture:

Sketch picture includes the following capabilities:

• Insert pictures(.bmp, .gif, .jpeg, .tif, .tiff, .wmf, .png, .psd) on sketch plane.
• Use pictures as an overlay for creating 2D sketches.
• Convert raster data to vector data using Autotrace.

 

Features:

Features are the individual shapes that, when combined, make up the part. We can also add some types of features to assemblies.

              Fig. Shows the list of features in SolidWorks

 

Surfacing Tools:

• Extrude
• Revolve
• Sweep
• Loft
• Fillet
• Trim
• Untrim
• Extend
• Thicken
• Offset
• Radiate
• Ruled
• Boundary
• Fill

Knit:

• Knit function is similar to the solid feature Combine in that it joins multiple surface bodies into a single surface body.
• Unlike Combine, Knit doesn’t perform the subtract or intersect Boolean operations.
• Knit feature has an option to create a solid if the resulting surface body meets the requirements (a fully enclosed volume without gaps or overlaps).
• However, unlike the solid bodies in Combine, which may overlap volumetrically, surface bodies must only intersect edge to edge more like sketch entities touch end to end.

Trim:

• The trim function in SolidWorks is analogous to the Extrude Cut in Solid Modelling.
• We can use sketches, planes, or other surface bodies to trim a surface body.
• When we trim a surface, we can choose to delete the either side of the Trim tool.
• With a mutual trim, both surfaces can be trimmed. A mutual trim usually leads to a corner created by the intersections of two surfaces.

Untrim:

• The Untrim function is predictably the opposite of trim.
• It removes the boundary from a surface.
• Untrim restores the natural four-sided boundary that was changed by being trimmed by adjacent surfaces.
• Untrim can remove the boundary selectively (one edge at a time, interior edges only) or remove all the edges at once.
• Untrim works as imported geometry.

 

• Untrim works on native and imported geometry.
• It is not truly like imported geometry, but it does help to uncover the underlying original shape of the face.

Ruled Surfaces:

• Ruled surfaces are defined as surfaces on which a straight line can be drawn at every point.
• Ruled surfaces are used frequently in plastic parts and plastic mold design where draft and parting surfaces from 3D parting lines are needed.
• The Ruled Surface feature in SolidWorks is one of those features that we may never miss until we see it in action. It’s extremely useful for constructing faces with draft, extending faces tangent to a direction, making Radiate Surface types, building molds, and other applications.
• A ruled surface requires a model (surface or solid) edge from which to start. We cannot create a ruled surface from a sketch or curve. The icon will not become active until we have solid or surface geometry in the graphics window.
• 

Fig. Shows the Ruled Surface property manager interface

 

• The Ruled Surface feature works from the edge of a solid or surface body. The feature has 5 basic types of operations that it can perform:
• Tangent to Surface
• Normal to Surface
• Tapered to Vector
• Perpendicular to vector
• Sweep
• Tangent to Surface:
• The Tangent to Surface setting creates a surface that is tangent to the surface of the selected edge.
• Normal to Surface:
  • With the Normal to Surface setting, it tilts up 5 degrees from the horizontal because the surface is lofted with a 5-degree draft angle at the big end, making a ruled surface that’s normal.
• Tapered to vector:
  • The Tapered to vector setting needs a plane or axis selection to establish a direction, and then a ruled surface is created from that reference at the angle that we set.
  • With the combination of the Alternate Side button and the arrow-direction toggle button next to plane selection, we can adjust the cone created by this setting.
• Perpendicular to Vector:
  • The Perpendicular to vector setting is better option than the Normal to Surface setting when the surface has been created with some sort of built-in draft angle.
• Sweep
  • The Sweep setting makes a face that’s perpendicular to the surface created by Perpendicular to Vector. It’s as if a straight line were swept around the edges. This is actually a great way to offset an edge. This is actually a great way to offset an edge or 3D sketch: using the edge of the surface as the offset of the original.

 

Extruded Surface:

• The Extruded Surface works exactly like an extruded solid, except that the ends of the surface aren’t capped.
• It includes all the same end conditions, draft and contour selection, sketch rules and so on.
• 

              Fig. Shows the property manager of Extruded Surface.

 

• We can create extruded surfaces from open or closed sketches, with open probably being the most popular type.

Boundary Surface:

• The Boundary surface feature was created as a higher quality replacement for Loft feature, but certain limitations mean that Loft has not been removed from the feature list in SolidWorks.
• The Boundary Surface feature resembles a loft, but it has elements of the sweep and fill.
• Loft also does a Boundary Surface cannot, such as a closed loop loft without a direction 2 curve, and most importantly a centerline loft.
• Boundary Surfaces can use sketches, curves, or edges in several arrangements, such as curves arranged in an X, F, E, T, L, and other shapes.
• Below fig. shows some of these shapes:
• 

Fig. Shows use of different curve arrangements with the

              Boundary Surface feature

 

• If several edge or sketch segments combine to form a curve in one direction, then we must use the Selection Manager to form the edge segments into a group.
• Selection Manager enables us to select potions of a single sketch or to combine elements such Sketch, Edge and Curve into a single selection for use as a profile or guide curve for Boundary or Loft features.

 

              Fig. Shows the Boundary Surface property manager

 

• The main advantage of Boundary Surface over Loft is that Boundary Surface can apply a curvature boundary condition all the way around while Loft cannot apply curvature continuity across the guide curves.

Fill Surface:

• The Fill Surface is the one of the most powerful tools in the surface modeler’s toolbox.
• It is intended to create oddly shaped holes between surface bodies. We can use constraint curves to drive the shape of the fill between the existing boundaries.
• It can also knit a surface body together into a solid, all in one step.

Offset Surface:

• The Offset surface feature’s closest relatives are the Thicken feature and the Sketch Offset.
• It also fails for some reasons. For example, if you offset a 0.25-inch radius arc by 0.3 inches to the inside, it will fail because it cannot be offset up to or past a zero radius.
• The same is true for Offsetting Surfaces.
• We can use offset surfaces to copy the surface by zero distance to create a new surface.

This is usually done to copy either solid or surface faces to make a new surface body.

 

Thicken Surface:

• The thicken surface feature is used to create a solid from a surface.
• If a surface body that encloses a volume is selected, then the option Create Solid from enclose volume appears in the Thicken Property manager
• 

Fig. shows the feature property manager

              Of thicken feature

Planar Surface:

• Planar Surfaces can be created quickly and are useful in many situations, not just for surfacing work.
• Because they are by definition planar, we can sue them to sketch on and for other purposes such as we can use as a plane for mirroring, cutting and dimensioning.
• However, planar surfaces are created from a closed sketch such as a rectangle.

Extend Surface:

• The Extend surface feature functions in much the same way as the Extend functions works in sketches.
• However, spline-based surfaces are more difficult to extend than sketch entities.
• 

                             Fig. Indicates the property manager of Extend Surface

 

Aston-Martin One-77:

Step : 1 Insertion of blueprints on specific planes

Step : 2 Surface Modelling of Roof

Step : 3 Surface Modelling of Side Rails

 

Step : 4 Surface modelling of Front and Rear fenders

 

 

Step : 5 Surface Modelling of Front Bumper

 

Step : 6 Surface Modelling of Rear Bumper and Windows

 

 

Step : 7 Surface Modelling of Doors

Step : 8 Creating Front and Rear Winshields, Side mirrors and Saving them as   

new part file

 

Step : 9 Detailing of Hood and saving as new part file

 

Step : 10 Hybrid Modelling of Rear Bumper

 

 

Step : 11 Surfacing of Lights

 

 

Step : 12 Hybrid Modelling of Grilles

 

 

 

Step : 13 After saving the parts as different files, also save the car body new      part file.

 

 

Step : 14 Solid Modelling of Rim

Step : 15 Solid Modelling of Tyre

 

 

Step : 16 Saving the Wheel Subassembly after the disc-brake and caliper has been created

Step-17 Emblem

           

Step : 18 Assembly

 

 

 Renderings:

Conclusion: 

With the completion of this project I have learned how to do class A surfacing in SolidWorks

 

References:

Book: Mastering SolidWorks – MattLombard

https://help.solidworks.com/2018/english/SolidWorks/sldworks/c_Sketch_Picture.htm

 Link for files:

https://drive.google.com/drive/folders/1DrQimzm78vvo3I2s7uRgoqMaSSqOXDG5?usp=sharing