3.4 Computer-aided design (CAD)
Essential Idea
A computer-aided design is the generation, creation, development and analysis of a design or system using computer software.
Nature and Aims of Design
Nature of design:
As technologies improve and the software becomes more powerful, so do the opportunities for designers to create new and exciting products, services and systems. Greater freedom in customization and personalization of products has a significant impact on the end user. The ability to virtually prototype, visualize and share designs enhances the whole design cycle from data analysis through to final designs. (1.14)
Aims:
Aim 10: The use of CAD to simulate the conditions in which a product will be used allows the designer to gain valuable data at low cost. For example, simulating the flow of air across a car exterior negates the need for a car and wind tunnel.
Guidance
As a student of Design Technology, you should:
Identify the advantages and disadvantages of using computer-aided modelling
Understand how data models structure data through database models
Understand that the design of information systems enable the exchange data
Understand how haptic technology, motion capture, VR and animation can be used to simulate design scenarios and contexts
Be able to compare FEA testing strategies with physical models testing
Understand how FEA systems are used when designing and developing products
Korean text
Summary
컴퓨터 지원 설계 (CAD)는 디자이너가 혁신적인 제품과 서비스를 만들고 분석하며 개발하는 강력한 도구입니다.
CAD를 사용하면 가상 프로토타이핑, 시각화 및 디자인 공유가 가능하여 전체 디자인 프로세스를 개선할 수 있습니다.
2D 및 3D 소프트웨어와 같은 다양한 유형의 CAD 소프트웨어가 디자인 프로세스 전반에 걸쳐 실제적인 가상 디자인을 만드는 데 사용됩니다.
표면 모델링 또는 솔리드 모델링을 사용하여 CAD 모델을 생성할 수 있으며, 크기, 재료, 부품 및 기능에 대한 자세한 정보를 제공합니다.
CAD의 장점은 빠른 변경, 쉬운 커뮤니케이션, 비용 및 낭비 감소이며, 단점은 비용과 전문 교육이 필요하다는 것입니다.
유한 요소 분석 (FEA) 및 가상 프로토타이핑은 디자이너가 물리적 프로토타입을 만들기 전에 디자인을 테스트하고 개선할 수 있는 도구입니다.
디자인에 사용되는 다른 기술에는 디지털 인간, 동작 캡처, 햅틱 기술 및 가상 현실 (VR)이 포함되며, 안전성, 편안함 및 효율성을 향상시킵니다.
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애니메이션은 프로세스 시뮬레이션 및 제품의 형태와 기능을 보여주는 강력한 도구입니다.컴퓨터 지원 설계(CAD)는 디자이너가 혁신적인 제품과 서비스를 만들고 분석하며 개발하는 강력한 도구입니다. CAD 소프트웨어를 사용하면 디자이너는 제품을 맞춤화하고 개인화하는 기회를 갖게 되어 최종 사용자에게 혜택을 제공할 수 있습니다. CAD는 가상 프로토타이핑, 시각화 및 디자인 공유를 통해 전체 디자인 프로세스를 개선하는 기능도 제공합니다.
CAD의 한 목표는 낮은 비용으로 가치 있는 데이터를 수집하기 위해 제품 조건을 시뮬레이션하는 것입니다. 예를 들어, 자동차 외부에 대한 공기 흐름을 시뮬레이션함으로써 물리적 테스트의 필요성을 없앨 수 있습니다. 디자인 기술 학생으로서 컴퓨터 지원 모델링, 데이터 모델링 및 정보 시스템 설계의 장단점을 이해하는 것이 중요합니다.
2D 및 3D 소프트웨어와 같은 다양한 유형의 CAD 소프트웨어가 디자인 프로세스 전반에 사용됩니다. 이러한 프로그램은 디자인의 현실적인 가상 표현을 만드는 데 도움이 되며, 클라이언트에게 보여주거나 광고에 사용할 수 있습니다. Parametric 모델은 빠르고 정확한 변경을 가능하게 하며, surface 및 solid 모델은 디자인에 대한 다양한 수준의 세부 정보를 제공합니다.
CAD 모델은 surface 모델링 또는 solid 모델링을 사용하여 생성할 수 있습니다. Surface 모델링은 디자인의 외관에 초점을 맞추고, solid 모델링은 내부 부품 및 구성 요소에 대한 정보를 포함합니다. Solid 모델은 크기, 재료, 부품 및 기능에 대한 상세한 정보를 제공하며, CAD/CAM 기술을 사용하여 디자인을 만드는 데 사용할 수 있습니다.
CAD 소프트웨어를 사용하는 것에는 장단점이 있습니다. 빠른 변경, 쉬운 커뮤니케이션, 비용 및 폐기물 절감이 가능하지만, 비용이 많이 들고 전문 교육이 필요할 수 있습니다. 또한 디자이너는 bottom-up, top-down 또는 hybrid 접근 방식과 같은 다양한 전략을 사용하여 CAD 모델을 개발할 수 있습니다.
유한 요소 분석(FEA)은 물리적 프로토타입을 만들기 전에 디자이너가 디자인을 테스트할 수 있는 강력한 도구입니다. FEA에는 피로 및 열 분석이 포함되어 있어 디자이너가 디자인 내구성과 열 분포를 이해하는 데 도움이 됩니다. 가상 프로토타이핑은 디자이너가 현실적이고 대화식 모델을 만들 수 있는 또 다른 도구로, 초기에 실수를 잡아 시간과 비용을 절약할 수 있습니다.
디자인에 사용되는 다른 기술로는 디지털 인간, 동작 캡처, 햅틱 기술 및 가상 현실(VR)이 있습니다. 이러한 기술은 디자이너가 디자인에서 안전성, 편안함 및 효율성을 보장하는 데 도움이 됩니다. 애니메이션은 또한 프로세스를 시뮬레이션하고 제품의 형태와 기능을 보여주는 데 사용할 수 있는 강력한 도구입니다.
결론적으로, CAD는 디자이너에게 맞춤화, 가상 프로토타이핑 및 개선된 디자인 프로세스를 제공하는 가치 있는 도구입니다. 다양한 유형의 CAD 소프트웨어, 모델링 기술 및 분석 도구에 대한 이해는 디자인 기술에서 성공을 위해 중요합니다. 또한 동작 캡처, 햅틱 기술 및 VR과 같은 신흥 기술에 익숙해지면 디자인 프로세스를 향상시키고 최종 제품의 품질을 향상시킬 수 있습니다.
Chinese text
Summary
计算机辅助设计（CAD）是设计师创建、分析和开发创新产品和服务的强大工具。
CAD允许进行虚拟原型设计、可视化和设计共享，改善整个设计过程。
不同类型的CAD软件，如2D和3D软件，在整个设计过程中用于创建真实的虚拟设计表示。
CAD模型可以使用表面建模或实体建模创建，提供有关尺寸、材料、零件和功能的详细信息。
CAD的优点包括快速更改、简便的沟通、降低成本和减少浪费，而缺点包括费用和专业培训。
有限元分析（FEA）和虚拟原型是设计师在制作物理原型之前测试和改进设计的工具。
设计中使用的其他技术包括数字人类、动作捕捉、触觉技术和虚拟现实（VR），提高设计的安全性、舒适性和效率。
动画是模拟过程和展示产品形式和功能的强大工具。
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计算机辅助设计（CAD）是设计师用来创建、分析和开发创新产品和服务的强大工具。借助CAD软件，设计师有机会定制和个性化产品，使最终用户受益。CAD还允许虚拟原型设计、可视化和设计共享，改善整个设计过程。
CAD的一个目标是模拟产品条件，以低成本收集有价值的数据。例如，模拟汽车外部的气流可以消除对物理测试的需求。作为设计技术的学生，了解使用计算机辅助建模、数据建模和信息系统设计的优缺点非常重要。
设计过程中使用不同类型的CAD软件，如2D和3D软件。这些程序帮助创建逼真的虚拟设计表示，对于向客户展示和广告宣传非常有用。参数化模型可以快速准确地进行更改，而表面模型和实体模型则提供有关设计的不同详细程度的信息。
可以使用表面建模或实体建模创建CAD模型。表面建模侧重于设计的外观，而实体建模则包括有关内部零件和组件的信息。实体模型提供有关尺寸、材料、零件和功能的详细信息，可以使用CAD/CAM技术制作设计。
使用CAD软件有优点和缺点。它可以实现快速更改、简化沟通，减少成本和浪费。然而，它可能成本高昂，并需要专门的培训。设计师还有不同的CAD模型开发策略，如自下而上、自上而下或混合方法。
有限元分析（FEA）是一种强大的工具，允许设计师在制作物理原型之前测试他们的设计。FEA包括疲劳和热分析，帮助设计师了解设计的耐久性和热分布。虚拟原型设计是另一种工具，允许设计师创建逼真的交互模型，通过及早发现错误节省时间和金钱。
设计中使用的其他技术包括数字人体、动作捕捉、触觉技术和虚拟现实（VR）。这些技术帮助设计师确保设计的安全性、舒适性和效率。动画也是一种强大的工具，可以用来模拟过程并展示产品的形式和功能。
总之，CAD是设计师的宝贵工具，可以实现定制化、虚拟原型设计和改进设计过程。了解不同类型的CAD软件、建模技术和分析工具对于在设计技术中取得成功至关重要。此外，熟悉动作捕捉、触觉技术和虚拟现实等新兴技术可以增强设计过程并提高最终产品的质量。
Concepts and Principles
Concepts and principles:
Types of CAD software
Surface and solid models
Data modelling including statistical modelling
Virtual prototyping
Bottom-up and top-down modelling
Digital humans: motion capture, haptic technology, virtual reality (VR), and animation
Finite element analysis (FEA)
Guidance:
Advantages and disadvantages of using computer-aided modelling
How data models structure data through database models
Design of information systems to enable the exchange data
How haptic technology, motion capture, VR and animation can be used to simulate design scenarios and contexts
Comparison of FEA with testing physical models
Use of FEA systems when designing and developing products
Types of CAD software
CAD stands for Computer Aided Design.
CAD software is used in various stages of the design process to create, modify, and evaluate designs.
2D Software
Software that produces a 2D image of a design. These images are used to communicate about the design.
Adobe Illustrator
Adobe Photoshop
3D Software
Software that creates a 3D model that contains information about about the dimensions, materials, etc. of the design. This information can be used to produce the design using CAM.
Autodesk Fusion 360
Autodesk Inventor
SketchUp
Solidworks
Rendering Software
Software that creates a realistic, but virtual representation of a design. This is used to present the design concept to clients and for advertising.
Blender
Maya
3D Studio Max
Use Cases
to create digital drawings that can communicate concepts and information to a client;
Serve as a foundation for refining a design;
Some 2D drawing file formats (DFX, for example) can be used to by CAD equipment such as laser cutters and routers;
Presentation of schematic drawings such as circuits, floor plans, etc.
Use Cases
Creation of parametric models that can be used by CAM equipment to produce the final product;
Present and explore concepts before going into production or prototyping;
Calculate material properties of a design using Finite Element Analysis (FEA).
*Parametric models: 3D models that are defined by constraints and features. This type of modeling allows for changes to be quickly and accurately made and updated automatically. The kind of models you build in Fusion 360 are parametric models
Use Cases
presentation of design to clients
preparation of advertising and promotion materials
Surface Modeling and Solid Modeling
There are many ways to create a CAD model. The way a model is created determines the type of information and detail contained in the model.
Surface modeling
Surface modeling, sometimes called rendering, only communicates information about the surface of the design. Rendering software uses data about the surface qualities, material, lighting, etc., to create a virtual representation of the product. There is no information about the interior of the product, the parts, or components.
These types of models are usually presented as 2D graphics files (JPEG, PNG, TIFF, etc.) or animated videos. Blender, Maya, and 3D Studio Max are examples of surface modeling programs.
Purpose: To communicate the aesthetic form and scale of an object.
Audience: Clients who want to understand how a design will look. Designers who want to quickly communicate ideas fro form.
This image of a Dyson hair dryer is created as a 3D model. However, the data in the file can only be used for 2d graphics, and animation. There is no information about the internal components, materials, etc. The model does not contain information that another machine (like a 3D printer) could use to produce the part.
Solid models, on the other hand, are accurate digital models of the whole part or object. They contain information that can be used by CAM hardware to produce the part or object. Solid model file formats include STL, commonly used for 3D printing.
Purpose: To communicate in great detail the dimensions, materials, components, function, etc of a design. To provide detail that can be used in the manufacture of the design using CAD/CAM technologies
Audience: Designers and Manufacturers who need information about how to manufacture the design using CAD/CAM technology.
This example of a drone contains information about the form and shape, but also materials, dimensions, etc. The information in this CAD model could be used by other machines (like a 3D printer, for example) to produce the product.
Advantages and Disadvantages of CAD software
Advantages
Changes, iterations and modifications to ideas can quickly be made;
Convenient communication between designer and clients, teams, and manufacturers
Electronically stored and transferred files are safe, secure, and easily shared.
Modeling can reduce costs and risks by identifying errors before full scale manufacturing
Reduced costs and waste as fewer physical prototypes need to be manufactured
Time and resources can be saved through efficient work practices
High accuracy of design and product
Disadvantages
Software can be expensive
Specialized training required can be time consuming and expensive
CAD Modeling Strategies: Top-Down, Bottom-up, or Hybrid
Designers have several strategies by which they can approach developing a CAD model. It is important to consider which strategy is best suited for the design goal.
Bottom-Up Strategies
Top-Down Strategies
Features
Design begins with detailed criteria and specifications
Individual parts are designed separately and then assembled into the final design
There is no relationship between parts - if a dimension is changed, associated dimensions must be changed indivually
Components can be reused across multiple assemblies
Design begins with criteria and parameters and is then developed as concept
New features and parts are added as the design evolves
Related parts are connected - if one dimension is changed, associated dimensions on other parts will also be adjusted.
The final design is a collection of inter-related parts that are uniquely design.
Use Cases
Detailed and precise parameters and design specifications are established before the actual designing takes place
Few or limited changes are anticipated
Large complex systems (buildings, spacecraft, vehicles)
Designing products that are made from standard parts
The design begins as a concept, with some design specifications established.
Design is expected to evolve through numerous iterations - numerous changes are expected
Product design of unique consumer products
Hybrid / Middle Out
A combination of both approaches. Some of the parts are designed individually (bottom up) while others are designed using the relational Top-down approach. Most modern CAD software allows a combination of both approaches.
Data Models
These types of models typically consist of a database or data set that is used to present and or understand the performance fo a design. Data modeling is based on the requirements for for the use context or application.
Data models can be structured either as a flat, hierarchical or relational databases.
Using motion capture technology, accurate data can be gathered to understand the performance and design context.
Motion tracking in Logger pro is one tool that can be use to generate data.
Autodesk using generative design and BIM (Building Information Modeling) to design the layout of their Toronto offices. Data on daylight, views, needs, worker preferences, etc., were used to optimize the workspace.
Finite Element Analysis (FEA)
Finite Element Analysis (FEA) is the calculation of loads and stresses on a product using CAD software. FEA uses a computer model of an object that is then analyzed to how it reacts when certain stresses such as heat, force, or load are applied.
FEA is a powerful tool that allows a designer to virtually evaluate the suitability, durability, and strength of design before producing a costly physical prototype.
Two common forms of FEA that a product designer might perform are:
Fatigue: to analyze the durability of a product. To determine where cracks might propagate in the design
Heat: to analyze how heat is transferred through the product. To determine where hot spots might be in a design and if these may degrade the design
FEA analysis of the bicycle frame above shows areas of great stress (Red), and low stress (Blue)
Virtual Prototyping
Prototyping is the use of CAD to develop realistic, interactive models. These virtual models allow the designer to simulate the design, communicate with clients and the design team, and explore the design. Virtual prototyping is powerful tool because it can:
reduce development costs by identifying errors without the need to produce physical prototypes
improve quality of the final product as performance characteristics can be analyzed and confirmed before production
reduce development time as designs can quickly be created and modified based on feedback from the client, engineers, etc.
Virtual prototyping can involve various aspects of CAD, from Solid or Surface models, FEM, to video fly-throughs.
Digital Humans, Motion Capture, Haptic Technology, Virtual Reality (VR), and Animation
Digital Humans
Digital simulations of the biomechanics of the human body. These kinds of models are used to predict how humans will move and interact with a virtual prototype.
Using digital models of humans designers can analyze and confirm:
Safety and Comfort
ensure there is enough space to perform a maintenance task (i.e. Is it possible to remove a part by hand and replace it?)
ensure that controls are accessible and adjustable (Can the dashboard controls of the car be reached by a seated and belted passenger?)
ensure that tasks do not require excessive force to perform by hand (Can a handle be turned comfortably?)
Efficiency
ensure equipment, controls, and machines are positioned to save time and avoid hazards
Digital Humans being used in Seimen's Technomatix software to analyze accessibility of controls in a vehicle.
Motion Capture
Motion capture is the recording of actual human movement using video, magnetic, or electro-mechanical devices.
Motion capture systems use some type of reflective, LED, magnetic, or acoustic marker that is connected to the joints.
To produce a motion capture, the movements of a human are captured and then mapped to a digital model. The capture recuords just the movements, not the physical appearance of the model. The movements are much more natural looking, and much time (and cost) is saved.
Models can only perform movements that are anatomically possible. Using a system such as MVN Analyzer from Xsens (see video) also allows for the real-time capture of accurate kinematic data.
In addition to the obvious use in animation and entertainment, motion capture can also be used to analyze how different users interact with a product, with the goal of improving safety and ergonomics.
Haptic Technologies
Haptic technologies use the sense of touch to provide feedback to the user. When interact with haptic technologies when our mobile phone vibrates when you press a button. More recently, some touch pads on notebook computers provide haptic feedback to the user as the move the mouse around the screen. It is also used in many gaming consols
Haptic technologies allow the user to interact more closely with the computer simulation and to respond to feedback from the system. Remote surgery systems rely on haptic feedback to communicate to the surgeon the nuance of the operation.
This haptic glove, the AxonVR, uses micro-pockets of air in the touch surfaces to communicate touch to the user.
Virtual Reality (VR)
Virtual reality technologies create a virtual environment where the user can interact with it in a realistic way. VR technologies rely on wearable technologies such as a helmet and goggles as well as haptic technologies to provide feedback to the user.
As seen in the video of Ford's Immersive Vehicle Environment Lab, VR technologies can provide valuable feedback about the design, ergonomics, use, and safety of a design. Because of its virtual nature, changes can be easily and quickly tested, saving time and development costs.
In addition, valuable data can be gathered about how users interact and use a product.
Ford's Immersive Vehicle Environment Lab is used to evaluate safety and ergonomic features of a car. Note how the system uses a combination of VR, Haptic, and Motion capture technologies.
Hyundai uses VR Tech as part of the design process to explore ideas, collaborate, and test concepts.
Animation
Animation can be used to simulate a process. It can be used to confirm the placement of equipment and determine safety, ergonomics, and efficiency of a factory layout.
Animation can also be used to communicate form and function of a product.