Design Technology | Unit 3. Modelling

Sketching

Ideation helps communicate ideas solidify rough concepts

Types of Cad softwares

2D Autodesk AutoCAD Adobe Illustrator 3D Autodesk Inventor or inventor Fusion SketchUp Solidworks Rendering 3D Studio Max Blender Maya Inventor & Solidworks have some capability as well

Purpose of 2d and 3d freehand drawings

3d sketches provide designers with a sense of form, proportions, and aesthetics 2d sketches detail structural features

Vector graphics

Graphics that use points, lines, curves, and shapes based on mathematical equations to represent images.

Haptic technology

Haptic technology is an emerging technology that interfaces the user via the sense of touch.

Attribute Listing

Technique which attacks problem by listing various characteristics then thinking of ways to improve each characteristic

Steps of rapid prototyping

Using CAD software produce a full scale model Export or convert model in STL (Standard Triangle Language and Standard Tessellation Language). send to RP machine manufacture the item clean up the item

What are Digital Humans?

computer based models that are designed to assist research on biomechanics and predict how human body would react to different situations (ie. human motions, forces, fatigue)

Low Fidelity (restricted)

conceptual representation analogous to the idea, for example paper prototypes. No really tangible. The user can offer input into the design idea.

Cabinet Drawing

depth is half the scale less depth distortion and appears more realistic

Cavalier Drawing

depth is shown to full scale

Animation

the ability of linking graphic screens to simulate motion or process - can be used to test different scenarios (can be dangerous)

three types of oblique projections

cavalier, cabinet, and general oblique

What is 3D Graphical Models?

- 3D sketches tend to provide designers a sense of form, proportion and aesthetics - 3D CAD require knowledge, skills and time to generate but it can be effective when interpreting or manipulating

What are the disadvantages of Rapid Prototyping?

- can be ineffective if it fails to replicate the real product - design steps are skipped hence many problems are overlooked and design may be flawed - may not be suitable for larger size product

What are the disadvantages of conceptual modelling?

- it can cause problem through the design process - the models may not be an accurate representative of the final product - simplicity can lead to vital aspects being left out - scale models can be misleading - it can be misinterpreted as there's lack of detail

What are the advantages of conceptual modelling?

- it is a creative and innovative method of thinking - clients can have input in developing the idea - save time and money by eliminating mistakes - speeding up the product development cycle - testing production methods before production - reviewing functionality of mechanism

What is a scale model?

- it is architectural concept models that are quick and inexpensive way to visualise - models use variety of materials to communicate materials and aesthetic appeal - clay modelling is also used (easy to manipulate) -maintains accurate relationships between the important aspects of the model

What are assembly drawing?

- it is often orthogonal - it is visually descriptive, showing actual configurations and fastening details.

What is a mathematical model?

- it is used in predicting systems and processes - these predictions can inform the designers of possible developments that are worthy to investigate (ie. materials, strength) - manufacturers use mathematical model to calculate and manipulate variable to optimise profits (ie. inventory, production time) - it is not entirely reliable when predicting real life situation

What is an aesthetic model?

- it is used to assess the appearance of the design - the view of aesthetics is based on culture, experience and emotions - it provides no information on the interior or functionality

What is a mock-up?

- mock ups are used to catch design flaws and acquire feedback ex. automobile testing in a wind tunnel ex. consumer goods to get the impressions on art and other factors behind product design ex. furniture-used to make a cheap full size replica to verify a design (proportion and spacial arrangement)

What are the advantages of CAD?

- models are real-life like - it can be stored in variety of formats - it enhances designers ability to see design flaws - it can be rescaled, zoomed, cropped and oheer - the model can be rapid prototyped -greater design quality -increases productivity and communication -greater freedom in the customization of products no physical components more accurate than hand drawn designs and reduces human error edit and save ideas choose pre-drawn designs

What is 2D Graphical Models?

- models that are used in early stages of the design process - 2D sketches tend to isolate details - they are quick to generate and useful for communicating initial design concepts

What are the advantages of Virtual Prototyping?

- modifications can be quickly evaluated in a time effective manner - costs will be reduced as materials are minimised - eliminate costly errors

What are the advantages of Rapid Prototyping?

- reduce time for development of product - reduce costly mistakes - increase product complexity - increase effective communication

What are the disadvantages of CAD?

- staff training is required - initial cost for software is expensive - constant requirement for upgrading softwares -requires a PC

What is a Scale Drawing?

- they are constructed to a specific ratio relative to the actual size of the object

What are the uses of sketches?

- used to quickly convey ideas - modify concepts - communicate with inside and outside design teams

Motion capture disadvantages

-specificity of software cost requirements for space hard to manipulate data results are limited without extra edition movement that doesn't follow the laws of physics cannot be captured

Steps of Sketching

1. mental visualization 2. outline 3. sharpening and darkening

Freehand sketching

A spontaneous representation of ideas on paper without the use of technical aids. perspective drawing, isometric assembly, orthographic projections, and annotated orthographic Advantages hand Quick Easy No specialised skills required No specialised equipment required Easy to communicate with manufacturer and client Disadvantages May not look like the intended outcome Lacks details

Morphological Synthesis

An elaboration of attribute listing. After completing the list of attributes, list them along two sides of a 2D grid.Think creatively about how the attributes can be developed through new ideas in each of the cells to improve the design.

2d CAD Software

Autodesk was the first traditional drawings like orthographic projection

What are the CAD modelling strategies?

Bottom Up (reengineering existing data structure forms) and Top Down Modeling (abstract way getting information about the subject from experts, serves as a reference point)

Bottoms up vs top down modeling

Bottom up: starts with an initial sketch in which the designer builds the design. Top down: starts with a 3D shape in which the designer removes material to build the design.

Brainstorming

Brainstorming combines a relaxed, informal approach to problem-solving with lateral thinking

Isometric assembly

Breaking down each part of a mechanical object to better understand its function Advantages Shows all views at once Easy to communicate with manufacturer and client Disadvantages Not all details are included May not look like the real thing

What is conceptual modelling?

Designers use conceptual modelling to describe a potential design solution or idea. - designers will be able to evaluate how effective the design is against the specifications and straighten their thinking before physically starting. -originates in the mind and its primary purpose is to outline the principles, processes and basic functions of a design or system. -the activity of describing major aspects of the design goal for the purposes of understanding and communication

What is 3D modelling?

It is a representation of the object - it can be further manipulated and changed without the need for a new drawing - it is suitable for testing new design and problem solving

What is Virtual Prototyping?

It is a software that simulate products and environment by mimicking real world behaviours - designers are able to simulate visually and mathematically - increase application in the development, testing and assessment of products

What is a wireframe modelling?

It is constructed surface by surface to produce a 3D representation of the object - it has the ability to rotate and examine the drawing from variety of perspectives

What is a prototype?

Models that include functionality aspect of a design - it should feel and look like a real product produced to provide full evaluation before mass production.

What the types of Digital Humans?

Motion Captures, Virtual Reality, Animation, Finite Element Analysis (FEA)

Third angle projecion

Object is positioned bellow and behind the viewing planes.

Annotated orthographic

Orthographic projection with descriptions

What is perspective drawing?

Perspective drawing is an observation based from a single point. - it creates the illusion that the further away the object is, the smaller it is. 2 Point Perspective - has 2 vanishing points 3 Point Perspective - has 3 vanishing points

Instrumented Models

Prototypes that are equipped with the ability to take measurements to provide accurate quantitative feedback for analysis. investigating hydraulic fluid flows

Raster Graphics vs Vector Graphics

Raster graphics are resolution dependent, meaning they cannot scale up to an arbitrary resolution without loss of apparent quality. This property contrasts with the capabilities of vector graphics, which easily scale up to the quality of the device rendering them. Raster graphics are more photo-realistic (computer PNG, IMG, JPEG) Raster program: photoshop vector graphics often serve better for typesetting or for graphic design Vector program: Adobe illustrator

What are the types of physical modelling?

Scale models, aesthetic models, prototypes, Mock-Ups

What are the types of Rapid Prototyping?

Stereolithography (SLA), Laminated Object Manufacturing (LOM), Fused Deposition Modelling (FDM), Select Laser Sintering (SLS)

First angle projection

The form of projection where the front view is located above the top view. Drawn using a six sided box

solid model

The model contains geometric information of all CAD models - it contains wireframe and surface information - it can be used for rapid prototyping

surface model

The surface or skin of the CAD object - produce a detailed view than wireframe models - it aims to produce a realistic effect - it is used to generate complex shapes quickly - no information is provided about the object's interior.

Form Study Prototype

This type of prototype will allow designers to explore the basic size, look and feel of a product without simulating the actual function or exact visual appearance of the product.

Steps of CAD

sketching of ideas modification analysis optimization of a design

Motion Capture advantages

assists the understanding of human factors, physical limitations and product evaluation - it is used to record, track and analyse movements - it creates a more natural movement than animation - reduce cost as it requires an animator to draw - it can help gather anthropometric data (safety factors) - it can be used at early stages of design process to reduce time an costs - digital humans reduces the need for physical model -quicker and costs are reduced

Top Down Modelling

a design that originates as a concept and gradually evolves into a complete product - it saves time throughout the evolution of design - reduce chances of error in complex assemblies

Parametric solid modeling

a solid modeling system that allows the user to vary the dimensions and other parameters of the model

Evolutionary Aesthetics

basic aesthetic preferences have evolved based on survival needs We look for regularity and symmetry

Aesthetics

branch of philosophy dealing with nature of beauty, art, and taste with the creation and appreciation of beauty studies sensory-emotional values

Pierre Bourdieu

examined how elite define aesthetic values cultural capital=education economic capital=money

Bottom Up Modelling

involves creating parts and then joining them together to form a product - it is time consuming when one modification to a part may affect other components

Scale Formula

ip/im ip=quantity value of the prototype im=quantity value of the model

What is Laminated Object Manufacturing ?

is a subtraction manufacturing technology - cuts each layer of a roll of material using laser beams - it is environmentally friendly and cost effective sometimes not super accurate though

What is Fused Deposition Modelling ?

is an additive manufacturing technology - operates layer by layer - the thin filaments are extruded through a heated chamber that converts into semi-liquid form. - it may not be accurate but models are strong and can be cleaned

What is Select Laser Sintering ?

is an additive manufacturing technology - uses high power laser (CO2 laser) to fuse small particles of plastic, metal, glass powder - operates layer by layer, a new layer pf powder is deposited with a roller - it has a rough finish

What is a Stereolithography?

is an additive manufacturing technology that build physical models using CAD - tank is filled in liquid plastic - UV laser beams shoots into the plastic and hardens - it produces smooth and quality surface for models and prototypes Advantages: fast and makes a wide variety of shapes Disadvantages: expensive

What is Rapid Prototyping?

is the production of physical model using 3D CAD data - increase effectiveness, costs and speed - it enables designers to produce a complex physical models

Finite Element Analysis (FEA)

it is used to test virtual models under variety of pressure or stress - this help with the material selection, manufacturing choices and costs

Fidelity

level of detail and functionality included in a prototype.

Software mockup

looks like the real thing, but doesn't function

What is an Orthographic Projection?

means of representing a 3-d object in two dimensions form of parallel projection where all projection lines are at right angle communicate the completed design - it provides a detailed information to manufacturers and engineers about dimensions, construction methods, materials and assembly. Advantages Detailed Contains all necessary information Can construct from it Accurate Easy to communicate with manufacturer Disadvantages Need specialised skills such as using CAD Specialised equipment needed Time consuming Not easily understood by a lay person (e.g. client)

High Fidelity (total)

mock-up of the idea, as close as possible to the final product, for example a full scale working prototype. They are tangible and testable. This allows full user interaction.

Performance capture

motion capture with face and fingers

Bourdieu Lifestyle Classification

need to know

Data modelling

process of creating a data model for an information system by applying formal data modeling techniques

Differences between prototype and production design

prototypes have low cost materials lost cost processing techniques low fidelity

Middle Fidelity (general or partial)

representation of aspects of the idea, such as, a working mock-up with limited functionality.

What is Graphical Modelling

same—to simplify the data and present it in such a way that understanding of what is being presented aids further development or discussion.

oblique projection

show the depth of an object

Virtual Reality (VR)

the ability to simulate a real situation and interact with it in a near natural way. - VR allow designers to predict how the model will perform when use and exposed to real world forces - VR provides feedback on ergonomics - reduce time and costs needed to produce a physical model

Lateral thinking

the solving of problems by an indirect and creative approach, typically through viewing the problem in a new and unusual light.

Physical modeling

three-dimensional, tangible representation or a design or a system Primarily used to test aspects of a product against user requirements allows for feedback and costumer interaction Advantages Explore and test ideas Easily understandable Communication with clients Communication with team members Ability to manipulate ideas better than with drawings Is tangible Can be used in user trails and user research more readily. Disadvantages Designers can easily make assumptions about how accurately a model represents reality It may not work like the final product Might not be made of the same material Time consuming to make Level of skill required Can be costly (prototypes)

Proof of Principle Prototype

used to test some aspect(s) of the intended design without attempting to exactly simulate the visual appearance, choice of materials or intended manufacturing process.

General Oblique

uses any reasonable scale. Allows perception to look natural. between 1/2 in and 1 in.