automotive design Automotive design is the process of developing the appearance (and to some extent the ergonomics) of motor vehicles, including automobiles, motorcycles, trucks, buses, coaches, and vans. The functional design and development of a modern mot ...

, a class A surface is a freeform surface of high efficiency and quality, in terms of aesthetical reflectivity. Strictly, class A surfaces have

curvature In mathematics, curvature is any of several strongly related concepts in geometry that intuitively measure the amount by which a curve deviates from being a straight line or by which a surface deviates from being a plane. If a curve or su ...

and tangency alignment. However, many people interpret class A surfaces to have G2 (or even G3) geometric continuity. Class A surfacing is done using

computer-aided industrial design Computer Aided Industrial Design (CAID) is a subset of computer-aided design (CAD) software that can assist in creating the look-and-feel or industrial design aspects of a product in development. CAID programs tend to provide designers with impr ...

applications. Class A surface modellers are also called "digital sculptors" in the industry.

Industrial design Industrial design is a process of design applied to physical Product (business), products that are to be manufactured by mass production. It is the creative act of determining and defining a product's form and features, which takes place in adva ...

ers develop their design styling through the A-Surface, the physical surface the end user can feel, touch, see etc.

Application

A common method of working is to start with a prototype model and produce smooth mathematical Class A surfaces to describe the product's outer body. From this the production of tools and inspection of finished parts can be carried out. Class A surfacing complements the prototype modelling stage by reducing time and increasing control over design iterations. Class A surfaces can be defined as any surface, that has styling intent, that is either seen, touched, or both and mathematically meets the definition for Bézier.

Automotive design application

application Class A surfaces are created on all visible exterior surfaces (ex; body panels, bumper, grill, lights etc.) and all visible surfaces of see-touch & feel parts in interior (ex: Dashboard, seats, door pads etc.). This can also include beauty covers in the engine compartment, mud flaps, trunk panels and carpeting.

Product design application

Back of iPhone 3G white showing the fixed focus 2 megapixel camera

In the product design realm, Class A surfacing can be applied to such things like housing for industrial appliances that are injection moulded, home appliances, highly aesthetic plastic packaging defined by highly organic surfaces, toys or furniture. Among the most famous users of

Autodesk Alias Autodesk Alias (formerly known as Alias StudioTools) is a family of computer-aided industrial design (CAID) software predominantly used in automotive design and industrial design for generating class A surfaces using Bézier surface and non-u ...

software in product design is

Apple An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...

Aerospace design application

Aerospace has styling and product design considerations in interiors like bezels for air vents and lights, interior roof storage racks, seats and cockpit area etc. In recent years

Airbus Airbus SE ( ; ; ; ) is a Pan-European aerospace corporation. The company's primary business is the design and manufacturing of commercial aircraft but it also has separate Airbus Defence and Space, defence and space and Airbus Helicopters, he ...

used ICEM Surf for generating the exterior surface geometry for

Aesthetics Aesthetics (also spelled esthetics) is the branch of philosophy concerned with the nature of beauty and taste (sociology), taste, which in a broad sense incorporates the philosophy of art.Slater, B. H.Aesthetics ''Internet Encyclopedia of Ph ...

and

Aerodynamic Aerodynamics () is the study of the motion of atmosphere of Earth, air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an ...

optimisation before delivering the surface to downstream CAD software like

CATIA CATIA (, an acronym of computer-aided three-dimensional interactive application) is a multi-platform software suite for computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), 3D modeling and product li ...

Clay modelling

Class A surfacing / digital sculpting is similar to clay modelling with the added advantage of computing power to change or incorporate design changes in existing/new design. Moreover, the revisions of clay modelling and refinement iteration are carried out in digital version. The scanned data of a selected clay model will be taken as a "Point cloud data" input, and Class A designers work on this Point cloud data to generate preliminary surfaces and further refine them to Class A surfaces.

Normalisation

Class A surfaces are currently not standardized, a team of French engineers propose a new idea for standardization: * Class A: G0/G1/G2/G3 – Good aesthetic quality of reflections * Class B: G0/G1 – Minimal classic quality (G0 = 0,001mm, G1 = 0.2° Max, Undulations Cu = 0.003mm-1, Radius minimum) * Class C – Surface holes/Bad tangents/Bumps/Undulations... Class C is a rough, poor surface, which will cause a problem in CAM/CAD and not aesthetically. Holes (G0), bad tangencies (G1), and micro Bumps that cannot be used for a ball cutter for example. Class B is the minimum quality for everything to go well in CAM/CAD. In Aeronautics, everyone is in Class B without Holes with good Tangencies (G1) and without unusable micro Bumps. Class A has the qualities of a Class B, but in addition is mainly in G2/G3 curvatures, allowing very beautiful aesthetic reflections, smooth and without cuts. Necessary for mass consumer products such as cars or iPhones.

Notable software

The most widely used software tools are Alias by

Autodesk Autodesk, Inc. is an American multinational software corporation that provides software products and services for the architecture, engineering, construction, manufacturing, media, education, and entertainment industries. Autodesk is headquarte ...

, ICEM Surf a standalone software, ICEM Shape Design and ICEM Shape Design AeroExpert followed by Dassault systems etc integrated in module in Catia V5.

References

{{DEFAULTSORT:Class A Surfaces Vehicle design Computer-aided design software Computer-aided industrial design Computer-aided design 3D computer graphics Surfaces Graphic design