Crucial notes for final exam PDF

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Spring 2015 – Main Exam STUDENT NUMBER: This paper and all materials issued must be returned at the end of the examination. They are not to be removed from the exam centre. Examination Conditions: It is your responsibility to fill out and complete your details in the space provided on all the examin...

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Spring 2015 – Main Exam

STUDENT NUMBER:

This paper and all materials issued must be returned at the end of the examination. They are not to be removed from the exam centre. Examination Conditions: It is your responsibility to fill out and complete your details in the space provided on all the examination material provided to you. Use the time before your examination to do so as you will not be allowed any extra time once the exam has ended.

Time Allowed: 3 hours and 10 mins Includes 10 minutes of reading time. Reading time is for reading only. You are not permitted to write, calculate or mark your paper in any way during reading time.

This is a Closed Book exam

You are not permitted to have on your desk or on your person any unauthorised material. This includes but not limited to: • Mobile phones • Smart watches and bands • Electronic devices • Draft paper (unless provided) • Textbooks (unless specified) • Notes (unless specified)

Please refer to the permitted materials below:

You are not permitted to obtain assistance by improper means or ask for help from or give help to any other person.

Materials provided for this exam:

You are not permitted to leave your seat (including to use the toilet): • Until 90 mins has elapsed • During the final 15 mins During the examination you must first seek permission (by raising your hand) from a supervisor before: • Leaving early (after 90 mins) • Using the toilet • Accessing your bag Disciplinary action will be taken against you if you infringe university rules.

48240 Design & Innovation Fundamentals

Permitted materials for this exam: •

Calculators (non-programmable only)

•

Drawing instruments i.e. Rulers, Set Squares and Compasses

•

This examination paper

•

Six (6) answer booklets (5-pages)

Students please note: •

This exam is worth 40% of the final mark

•

This exam is in two parts – Part A and Part B. You are to attempt both parts for a total of 100 marks. The marks for each individual question are shown.

•

You are to answer ALL four (4) questions from Part A (for a total of 60 marks)

•

You are to answer ANY two (2) questions from Part B (for a total of 40 marks)

•

Use a SEPARATE ANSWER BOOK for EACH Question.

•

Write the QUESTION NUMBER on the front cover of EACH answer book.

•

Write your NAME and STUDENT NUMBER on this examination paper (above), AND on the front page of EACH answer book.

Do not open your exam paper until instructed. Faculty of Engineering and IT

Page 1 of 2

By Oscar A. Nieves and Jion Rao

PART A – Answer All Four (4) Questions in this Part A. (60 marks total)

Q

Parts

Main Topics

1

a, b, c, d

2

a, b, c

• •

Marks

Concept of Operations, Requirements Analysis

10

10 •

Stage Gate Process

3

a, b, c

20

4

a, b

20

PART B – Answer any Two (2) questions from this Part B. (40 marks total)

Q

Parts

5

a, b, c

• •

Event Tree Analysis (calculations and interpretation of results) Piper Alpha Case Study

20

6

a, b

•

Fault Tree Analysis (calculations and interpretation of results)

20

7

a, b, c

•

Failure Mode and Effects Analysis (calculations and interpretation of results)

20

8

a, b, c

20

9

a, b, c, d

20

10

a, b, c, d, e

20

a, b, c, d, e

20

11

Main Topics

Marks

By Oscar A. Nieves and Jion Rao

PART A Question 1. Concepts of Operations and Requirements analysis 1. Concepts of operation and requirements analysis Early design In the design stage of any project it is important to identify the customer’s needs so that a solution to the specific problem can be developed based on available technology. Some things to take into consideration during design are:

• • • • • • •

Health and safety, quality of life of the public Improvements to existing products Advances in science and technology (e.g. materials and manufacturing) Analysis of the commercial viability of the product by comparison with other competitive products Analysis of the cost and revenue from the product Experience and skills of the engineer designing the solution/product to improve accuracy, efficiency and reduce material/resource wastage Products must respond to their customer’s needs to be successful

Types of problems Problem of prediction: calculating a result or predicting a system’s behaviour by using appropriate equations, theories and data analysis. Problems of explanation: searching the causes for a phenomenon or behaviour. Problems of invention: developing new effective solutions to a problem.

Product concept (concept of operation) The product concept often offers a way of how to address the stakeholders’ needs with adequate justifications. It may need approval from the business or customer before proceeding, and is used to analyse stakeholder needs and identify design requirements. It is then refined in the requirements specification. Customer needs 9 What the customer wants, would like 9 May not be practical (e.g. too futuristic, not achievable at the moment) 9 Can be too complex 9 No constraints, no limitations

Stakeholder needs 9 More specific than customer needs 9 Usually more realistic and specific to the stakeholder 9 Involves all of those affected by the design 9 Often has set limits and constraints

Design requirements 9 Must meet both customer and stakeholder needs 9 Must be practical, realistic, verifiable, unambiguous, abstract 9 Must follow the constraints of the stakeholders 9 Design must be innovative

Developing the concept A design strategy must be outlined and different concepts must be explored. They must then be compared in terms of their strengths and weaknesses, how they address the customer and

By Oscar A. Nieves and Jion Rao

stakeholder needs, and whether they can be a real-win-worth opportunity. Concepts should be reviewed and assessed based on cost, viability, competitiveness, practicality, etc. The best one should be chosen with adequate justifications (perhaps a rating or scoring system, a weighed matrix might be a good way to compare designs).

Where requirements are used Requirements define what the stakeholders need, a description of the proposed system and what the system must do in order to satisfy these needs. They are used in project planning, risk management, acceptance testing, trade-off and change control.

Requirements analysis and specification After having a product concept, it is necessary to identify the design requirements based on the needs and then perform a requirements analysis.

1. Needs analysis: assess the needs of the customer. Organise them into a statement of the design problem (avoid technical language). Analyse the needs based on the possibility of meeting them using available resources and technologies. 2. Problem statement: state the main problem to be solved by the design/product based on the needs analysis and the data gathered from it (what are the objectives that the proposed solution must satisfy). It should be written in the language of the customer and cover all aspects of the design, and contain enough information to allow the design to be transformed into a product. It should also state the goals and capabilities of the project and the key decisions to be made. 3. Requirements analysis: specify the design requirements based on the problem statement. Classify requirements into functional (those related to the operation of the product, which describe how it will work) and non-functional or performance (e.g. appearance, size, shape, external features that do not affect operation). All requirements must be: 9 Abstract: must state what the problem is and not give any specific information about how it will be solved. 9 Unambiguous: must be specific as to what constraints or aims the product follows (e.g. if the requirement of a new car is to travel at a higher speed, that speed must be specified in the requirement, otherwise it is not unambiguous). 9 Traceable: the requirement should be traced back to the stakeholder needs. 9 Verifiable: a test should be designed for the requirement and thus should be realistic and achievable. It must be testable and quantifiable within bounded target values. A requirement must first be unambiguous to be verifiable. 9 Realistic: within budget and time constraints, SMART (Specific, Measurable, Achievable, Realistic, Timeframed). 9 Technically feasible: must be achievable by available means (existing manufacturing technologies, materials, etc.). Use “will”, “shall” and “should” when stating the requirements. The next step is to design the criteria for evaluating the design.

4. Requirements specification: once the requirements have been analysed they must be presented in an appropriate format.

By Oscar A. Nieves and Jion Rao

Common problems with requirements specification ¾ Incorrect or poorly-specified requirements can create many problems during system integration, testing, manufacturing or deployment of the finished product. Examples may include: improper constraints or specifications, non-verifiable requirements, etc. ¾ Requirements are not always validated by the stakeholders; and as a result the end product is not acceptable for most of them, even if it is verified by the testing department.

Uses of the requirements analysis ¾ Customer agreement ¾ Reduce the development effort ¾ Provide a basis for estimating costs and schedules ¾ Provide a baseline for validation and verification ¾ Facilitate use and re-use ¾ Serve as a basis for enhancement Requirements validation To validate requirements, one can use the following table: Requirement Phone must have a battery life of 500 hours

abstract YES

unambiguous NO (500 hours performing what function?)

traceable YES (who wouldn’t want it?)

verifiable NO (no constraints specified)

realistic… NO (seriously, 500 hours of battery life?)

By Oscar A. Nieves and Jion Rao

PART A Question 2. Engineering Lifecycles & High Level Design 1. Engineering Lifecycles What is a lifecycle? A life cycle model is a decision-linked conceptual segmentation of the good or service and its utilization, evolution and disposal in the real world.

What is it important? These segments provide an orderly progression of a system through established decision-making gates to reduce risk and to ensure satisfactory progress. Benefits of using Lifecycle model: Primary – where you need to make a decision to specific criteria before a system can progress to the next stage. Secondary – where the organisation prefers to think of its work and its processes within a larger framework, which may have useful business relevance or alignment with supply chain or customer processes.

By Oscar A. Nieves and Jion Rao

High level design is performed in the functional domain, which means that customer needs are translated to functional requirements. Some of the benefits of high level design are:

¾ ¾ ¾ ¾ ¾ ¾

Improvements to decision-making process (is the design manageable?) Determination of acceptable performance limits from requirements Good estimation of the cost early in the project Reduced risk of malfunction and increased reliability of the system Reduction of development costs Provides a framework for the team to work on the design High level design consists of 5 steps:

1. Solution concepts: this step usually involves defining the problem and looking at the possible solutions.

2. Synthesis: this is the process of bringing structure to the initial solution concept. It starts as a rough sketch that becomes more refined as the design develops, and should contain enough detail for an analysis to be performed. Some difficulties that might need to be dealt with are: the need for the design to be completed quickly and superior cost or performance over competitors. 3. Analysis: this step involves breaking apart the synthesised system to verify if it will meet performance and cost objectives stated in the requirement specification. It can also help determine the risks involved in developing the design through detailed design and implementation. Some useful tools for analysis include mathematical models, computer models, computer simulations and physical experiments in a laboratory. Models are useful for observing and predicting how the system will behave in the future and what improvements can be done to accurately reduce the risk of system failure. 4. Refinement: after enough information from the analysis stage has been collected, the synthesised concept can be modified to improve its performance and reliability. Nevertheless, the refinement can take place during the analysis stage, as it will usually cycle between

By Oscar A. Nieves and Jion Rao

synthesis and analysis. The iteration (or repetition) of this cycle will be useful for implementing the results from a particular analysis to perform another analysis, or for obtaining successively closer approximations to the desired solution.

5. Documentation (system specification): this is used to complete the detailed design and implementation. It includes a record of the systems engineering process to assist in modifying the design if any problems/errors are found. It can also be used as a reference for future generations of the product and also to develop manuals, advertisement and technical support. Additionally, the system specification documents the function of each block in the block diagram, as well as the inputs and outputs, how the blocks work together, test plan, calculations, computer simulations and laboratory tests. It usually follows this structure: Introduction (project definition) Concept/objectives Principles of operation Background List of functional elements Block diagrams + inputs and outputs + process description + test plan (for each element) Description of system How individual blocks interact System analysis Results from mathematical analysis, simulations and laboratory tests

By Oscar A. Nieves and Jion Rao

Abstraction Abstraction helps avoid fixation on currently available solutions and identify fictitious constraints and to eliminate non-genuine restrictions. The steps for abstraction are the following:

1. From the problem statement, stakeholder impact and requirements specification, identify what are the required functions and the essential constraints. 2. Broaden the problem formulation and express the solution in the general form of the problem (this is known as ‘inventor’s paradox’). The inventor's paradox is a phenomenon that occurs in seeking a solution to a given problem. Instead of solving a specific type of problem, which would seem intuitively easier, it can be easier to solve a more general problem, which covers the specifics of the sought after solution. 3. Look for solutions to the general form (either on the same field or in a different one).

Decision analysis Design matrices can be particularly useful for comparing different solutions/concepts based on established criteria. The best design will be chosen based on how it meets each of the criteria and how it outstands from the alternative designs. There are 3 main types of design matrices:

¾ Alternatives evaluation matrix (Y and N): each design is evaluated in terms of whether it meets the criterion (Y) or not (N). The one with most Y’s is the most desirable.

¾ Non-weighed matrix: the criteria are not weighted in terms of importance and each design is rated using a specific scoring system for each criterion. The total scores are added for each design. ¾ Weighed matrix: the criteria are weighed in terms of importance (e.g. portability 10%, ease of use 15%, etc.) and designs are rated with a scoring system. Each score is multiplied by the weight of the respective criterion, and then all of these results are added. For example:

By Oscar A. Nieves and Jion Rao

PART A Question 3. Stage Gate Process, Industrial Design & DFX New product development process (NPD) A new product development process (NPD) is a process by which new ideas, concepts or suggestions are transformed into real products and services that cater the needs of the customers. This often involves the assessment and selection of different ideas and concepts and analysing the possible market success of each concept. One of the main objectives of the NPD process is to minimise the number of products that are cancelled in the later stages of development, where costs are much higher and the need for successful products is greater. Another objective of the NPD process is to accelerate the time for the product to be released on the market and reduce breakeven times, taking into consideration the continuous improvement of the product. Critical success factors for NPD These factors can be classified into three categories: project, people and environment and strategic. These are described below: 1. Project level:

a. b. c. d. e. f. g. a. b. c.

a. b. c. d. e.

Striving for unique superior products Market driven, customer focused Predevelopment work Stable project and product definition Planning and resourcing the launch Quality of execution of key tasks from idea to launch Speed (without compromising quality) 2. People and environment:

Organisation of project teams Climate, culture, environment Top management support 3. Strategic: Product innovation and technology strategy for the business Synergy and familiarity Targeting attractive markets Project portfolio management (PPM) – focusing on the business’s operational and financial goals A multi-staged, NPD process covering Idea-to-Launch

By Oscar A. Nieves and Jion Rao

Stage Gate Development model The main steps for this model are illustrated below:

1. Initial stage – discovery • Technical research and brainstorming of new, innovative, attractive ideas. • Uncovering unarticulated needs by working with lead users (e.g. innovative customers) and disruptions in the marketplace, which can lead to the identification of gaps and good business opportunities. • Suggestion schemes to encourage ideas from all employees. • Gate 1: analysing the project feasibility, existence of the market, product advantage, availability of resources and compliance with company’s policies. 2. Stage 1 – scoping

• •

Determining project’s technical and marketplace merits.

•

Market research studies including analysis of customer needs, wants and preferences for a winning product.

Preliminary market, technical and business assessment (usually takes 10 – 20 days for a person to complete) based on new, more detailed research. • Gate 2: re-evaluation of product based on new research, and subjection of project to “Go” or “No Go” decision. Financial return of the product may be assessed by simple calculations on payback period. 3. Stage 2 – building business case • Clear description of the product based on advanced research and verification of the product’s attractiveness.

By Oscar ...