ECE 495 - INTEGRATED SYSTEMS

1. ECE 495 - INTEGRATED SYSTEMS Requirements Specifications and Standards Timothy Burg

2. Life Cycle of a Troubled Project Project Initiation Wild Enthusiasm Disillusionment Search for the Guilty Change Punishment of the Innocent Promotion of the Nonparticipants Definition of the Requirements

3. In 1999, NASA lost the $125 million Mars orbiter Failure was attributed to conversion between metric and English measurement units between contractors Lockheed Martin used English measurements NASA navigation team used metric measurements The contractor, by agreement, was supposed to convert its measurements to metrics Design Example – Mars Orbiter Crash

4. Generic Design Process Lesson: A successful project will have a technical agreement between all parties (and they will monitor and enforce the agreement). Identify Need Retire Research Requirements Specification Maintain Use by Customer(s) Concepts Distribute and Sell Design Manufacture Prototype Testing

5. Requirements • Collection of engineering and marketing targets that a design must satisfy • Mission statement that drives all subsequent stages of development • Communication tool for everyone involved in the design; Engineering, Marketing, Client,… • In some cases serves as a legal binding contract Every important detail about what is expected is written in this document. All parties should understand the size, weight, reliability, electrical performance, etc. expected in the final product.

6. Design Example – Gamma-Ray Large Area Space Telescope (GLAST) Harmonize the vision for the telescope through a Requirements Document Design Team Customer’s Vision

7. Design Example – Gamma-Ray Large Area Space Telescope (GLAST) Gamma-Ray Large Area Space Telescope Telescope developed by NASA in collaboration institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States. The subsystems designed (independently) by each group must be assembled and work together to perform the function of GLAST Calorimeter: US, France, Sweden http://xweb.nrl.navy.mil/glast/

8. Design Example – Gamma-Ray Large Area Space Telescope (GLAST) One important component (PIN Diode)

9. Design Example – Gamma-Ray Large Area Space Telescope (GLAST) Used Standards to describe how routine items are done.

10. Design Example – Gamma-Ray Large Area Space Telescope (GLAST) Thousands of pages that describe what the system should do and how well. This all-sky view from GLAST reveals bright emission in the plane of the Milky Way (center), bright pulsars and super-massive black holes.

11. Two Types of Requirements Specifications • Marketing Requirements – What Customer “Wants” • “high-quality audio” • “fast” • “easy to use” • Engineering Requirements – Technical Targets • 2% distortion • 100 mph • 3 button interface, on-off, volume, balance

12. Marketing Requirements • Determine the voice of the customer. • May require asking what the customers wants • Customer may communicate solutions with the needs. • Need to understand source of solutions and if really appropriate • “I want a 1KW motor controller for …” may actually mean “I want to control the speed of the conveyer in …” . These are likely different solutions.

13. Engineering Requirements • Quantify the voice of the customer • 10 grams • 2% distortion • 100 mph • 3 button interface

14. Properties of An Engineering Requirement • Abstract • Specify what the system will do, not how • Unambiguous • Single stated meaning with short complete sentences • Traceable • Each requirement is a response to the customer’s need • Verifiable • Can measure that the requirement is met

15. Engineering Requirement Examples • Performance and Functionality • Accuracy and speed • Reliability and Availability • Failure rates and amount of time that a system is available for operation • Energy • Energy consumption • Operating lifetime +/- 0.1 mA, 800 mm/sec Mean time between failures (MTBF) = 30,000 hours <5W normal operation and <5mW sleep mode > 10 hours on single charge What is the common theme? We could measure the final system to see if it met these requirements. I can’t make a measure to determine if something is “fast” but I could measure if it moves at 800 mm/sec

16. Engineering Requirement Examples • Environmental • Temperature range, shock, vibration, EMI • Software and Computing • Data rates, system interface, data formats • Estimated learning time, menus, user error Operate in -20oC to 100oC ambient conditions. You are writing requirements for internet service, is this a good specification? It is great if you are the seller, terrible for the buyer

17. Need a Common Vision for a Design Project What sales department Sold to customer What engineering designed. How the software was written. How it was fixed in the field during installation. What the customer wanted We need a common vision. Why is this cartoon funny? Because it is so often true.

18. Thought Exercise • What are the Engineering Requirements you would give to someone to have them design a peanut butter and jelly sandwich? • If you were describing the requirements for a picnic, it would be nice to be able to say use the “standard peanut butter and jelly sandwich”.

19. Engineering Standards Help you leverage the wisdom and experience of many experts to describe the system to be designed. Document that tells how to do something or how something must behave.

20. Engineering Standards 550 standards issuing bodies in the United States • National Fire Protection Association (NFPA) • Trade association (organization founded and funded by businesses) • Publishes the National Electrical Code (NEC) • Federal Communications Commission (FCC) • An independent agency of the US government • Enforces standards • ANSI (American National Standards Institute) • Private non-profit organization • To aid portability between compilers defined ANSI C -> ISO C -> Standard C • ANSI paper sizes: A:8½ × 11

21. Engineering Standards 550 standards issuing bodies in the United States (cont.) • The Institute of Electrical and Electronics Engineers (IEEE) is a professional association • Professional society (EEs and CpEs) • 800 standards products • Examples: 802.11, FireWire • National Institute of Standards and Technology (NIST) • Government agency • Atomic clock, Weights and Measures • Antenna calibrations • 2012 budget $750,800,000

22. Engineering Standards – Must I Follow a Certain Standard in My Design? • “Voluntary” Standards • Adopted for the sake of ease of manufacture, interchangeability, and safety • May be used in an exclusionary way, to favor one group or organization over its rival • Mandatory Standards • Standards which are laws • Failure to follow would result in legal penalty • They are generally adopted out of concern for safety

23. Engineering Standards – Types of Standards • Definition Standards • Standards that provide standard measurement, symbology or terminology • SI or Standard system of measurement • Performance Specification Standards • Doesn't matter how a thing is made or done, but it defines a certain level of performance • Blu-Ray, USB 3.0, FireWire 800 (IEEE 1394b-2002) • Criteria Standards • How to go about an activity, kind of the "opposite" of a performance standard.

24. Example – US FCC Describes Use of the Radio Spectrum

25. Example – US FCC Describes Use of the Radio Spectrum • What type of standard? • Definition Standard • Performance Specification Standard • Criteria Standard • “Voluntary” or Mandatory Standard

26. Example: IEEE-STD-299-1997 Standard Method for Measuring the Effectiveness of Electromagnetic Shielding Enclosures • What type of standard? • Definition Standard • Performance Specification Standard • Criteria Standard • “Voluntary” or Mandatory Standard • Note: Cost $150 to purchase

27. Example – Standard for Specification of Requirements IEEE Standard 1233, Guide for Developing System Requirements Specifications Properties of the Requirements Specification (the set of all Engineering Requirements) • Normalized set • Complete set • Consistent • Bounded • Granular (Abstractness) • Modifiable

28. Engineering Standards – Who Writes Standards? You and your colleagues.

29. Standards and the Design Process Identify Need Standards give a good point to start or at least narrow down your research Retire Research Requirements Specification Maintain Usually standards help in describing expectations Use by Customer(s) Concepts Distribute and Sell Design Manufacture Prototype Testing Testing- Standards should be met for all tests conducted on product

30. Example: Marketing Requirements for a Controller for a Roller Bottle Incubator Apparatus System that turns bottles in an incubator. ? Motor and controller Cells Media What is in the Marketing Requirements and the Engineering Requirements?

31. Example: Marketing Requirements for a Controller for a Roller Bottle Incubator Apparatus The customer has asked for the following, what are the Marketing Requirements? Wheaton Science Products seeks an apparatus to enable you to easily scale-up anchorage-dependent cell lines from standard plastic flasks. Benefits of the Roller Bottles are the increased surface area, gentle agitation and improved gas exchange when cells are rotated out of the medium. All models are CE/UL/CSA marked for international use and are available with different electrical plug configurations. Economy bench models allow inexpensive entry into this technology with units rotating from one to eight bottles. For vaccine production or when high yield is needed, use the Wheaton Modular Cell Production Apparatus and add decks that will hold additional bottles, as needs increase. Backup battery systems and rotation alarms can also be added to any Wheaton Roller Production Equipment. Wheaton Roller Apparatus accommodates standard culture vessels, 108 to 121 mm in diameter and up to 550 mm long.. Rotation speed can be set by the user.

32. Example: Engineering Requirements for a Controller for a Roller Bottle Incubator Apparatus Map Marketing Requirements to Engineering Specifications • Gentle agitation -> acceleration rate rad/s/s • CE/UL/CSA marked -> • testing per UL standards **** • testing per CE standards **** • testing per CSA standards **** • International use -> 100V-240V input range • Economy, Inexpensive -> control system components <$5, installation < 2 minutes

33. Example: Engineering Requirements for a Controller for a Roller Bottle Incubator Apparatus Map Marketing Requirements to Engineering Specifications Include a similar table in your design report.

34. Summary – Two Types of Requirements Specifications • Marketing Requirements • Determine the voice of the customer. • Engineering Requirements • Quantify the voice of the customer • Properties of Engineering Requirements • Abstract (what not how) • Unambiguous • Traceable to customer need • Verifiable

35. Summary - Standards • Many Constraints on a Design • Standards summarize a class of constraints • Capture a body of experience • Conformance • Voluntary - not required by law • Mandatory - legal requirement • Contents • Definition - terminology • Performance – how well it should do some activity • Criteria – how to do something

36. Project 1 – Laser Cutter Demonstration

37. Project 2 Voltage Adapter A parts manufacturer has asked your team to propose an adapter design to interface between a General Performance Master Unit (Master Unit) and a General Performance Conditioning Module (Conditioning Module). The adapter will connect to a 9V supply that is accessible on the back of the Master Unit and supply 5V to the Conditioning Module. A general sketch of the desired adapter unit is shown in Figure 1. The Master Unit output voltage may be adjusted to exactly 9V (assume perfect voltage source). The Conditioning Module requires 5V ± 5%. The Conditioning Module consumes exactly 0.1W at 5V. An indicator light should be included to show that the adapter is functioning properly. The adapter must be implemented as a voltage divider with no active components. Design a device that meets the requirements above at the lowest cost (e.g. use a 10% over a 0.1% resistor if possible).

38. Project 2 Voltage Adapter • This is a design (you don’t physically build anything) • Prototype is a simulation – SPICE

39. Website • Your Team will use a website to build the final report • Hosting the Website • If you log onto Novell there should be a mapping U:\public.www which can then be accessed via the web as www.clemson.edu/~usernameFor example, you may create U:\public.www\index.htm and access as www.clemson.edu/~username/index.htm from a browser. • DO NOT USE Google or you will not be able to transfer at the end of the semester.

40. Individual Assignment • Respond to article at Forbes.com "Why Amazon Can't Make A Kindle In the USA" see website for instructions.

41. Questions ?