Consistent Terminology Consistent Results Introduction and Definitions 2005

Consistent Terminology, Consistent Results Introduction and Definitions 2005 MAPLD 5 Design Integrity Concepts

Agenda – Introductions and Definitions • Design integrity – A working definition • Why is this important? – A tale of two designs – Has anything changed? – Why should I care? • The miracle cloud • The alternative – Overview – Implications – Additional Definitions • Summary 2005 MAPLD 6 Design Integrity Concepts

Definition and Goal • Design – The invention and disposition of the forms, parts, or details of something according to a plan. (AH dictionary online) • Integrity – The state of being unimpaired; Soundness; The quality or condition of being whole or undivided; completeness (AH) • This seminar is intended to talk about techniques and issues that ensure the soundness and completeness of both the end product and the means used to produce it. 2005 MAPLD 7 Design Integrity Concepts

Design 1 – Radarsat 1 ACP 2005 MAPLD 8 Design Integrity Concepts

Radarsat 1 ACP Overview • Program dates: late 1990 – late 1992 • Specifications – Processor: 8 MHz 80386/80387 – Memory: 128 k x 8 SRAM, 128 kx 8 EEPROM, 16 k x 8 PROM – Interfaces: A/D (16), D/A (4 -12), Synchronous serial (3 input, 3 output), RS-232 GSE – Function: Attitude control processor for the RADARSAT 1 satellite – Logic Implementation MSI logic + PALs (16 L 8, 16 R 6, 16 R 8) • Additional functions (cross-strap, control) external 2005 MAPLD 9 Design Integrity Concepts

PAL Reminder 2005 MAPLD 10 Design Integrity Concepts

Design 2 - Command Telemetry Board (CTB) 2005 MAPLD 11 Design Integrity Concepts

CTB Overview • Program Dates: early 2001 – late 2003 • Specifications: – Processor: RTX 2010 (16 MHz) – Memory: 4 M x 8 (random), various FIFOs (16 k x 8) as necessary – Interfaces • • • MIL-STD-1553 B Synchronous Serial (command / telemetry) Analog input High-level discrete (output) Low-level discrete (input / output) – Functionality: S/C command/telemetry (level 0 and active) – Logic Implementation: 4 54 SX 32 S FPGAs • Additional resources (in same box): RAD 750, Mass Memory, Instrument Interface Card 2005 MAPLD 12 Design Integrity Concepts

What’s Changed? • Capability / Complexity • Logic Density • Specificity – RADARSAT (1 small specification with interface focus) – CTB (1 large specification with interface, s/w, operations focus) • Software Centricity • Initial Errors – RADARSAT: 3 jumpers; 1 PAL design change – CTB: 14 FPGA revisions • 2 spec change • 5 -6 mistakes • 6 -7 data dependency 2005 MAPLD 13 Design Integrity Concepts

What’s Not Changed? • • Overall program schedules Proportional budget Expectation of correctness Pain from mistakes 2005 MAPLD 14 Design Integrity Concepts

What Explains the Difference? • Engineers aren’t as capable? – Insulting! • Everything is just more complex? – Copout! • Methodology? – Methodology hasn’t changed • Always inadequate, we just got lucky • Adequate for old designs, no longer adequate – Methodology has changed • Used to be adequate, but we lost the recipe • Design philosophy of systems has changed? – Predicated on maximum flexibility – Expectation of extreme complexity – Over-specification – almost impossible to meet 2005 MAPLD 15 Design Integrity Concepts

What Do These Examples Illustrate? • The incidence of initial correctness for designs seems to be decreasing – Design changes seem to be more common – Problems late in the verification/validation cycle seem to be more frequent • Perhaps a combination of the factors presented explains this, but … – Desired complexity is not going to decrease – Budgets are not going to get bigger – The expectation of excellence isn’t going to go away • The only solution is to develop and improve a consistent methodology for implementing robustly designed products – Based on basic principles – Applicable to a variety of conditions 2005 MAPLD 16 Design Integrity Concepts

Why Should I Care? • Why do I work? – Self-actualization (fun, monetary reward, interest) • Why do people want us to work for them? – They need what we produce • What do people want engineers (especially in Aerospace) to produce? – A quality product that satisfies the customer’s needs • How do they want us to produce such a product? – Consistently and efficiently 2005 MAPLD 17 Design Integrity Concepts

The Layman’s View – The Miracle Cloud 2005 MAPLD 18 Design Integrity Concepts

The Miracle Cloud Method • Note that too many engineering schools teach this approach without meaning to • Advantages to the miracle cloud method – Total creative freedom • Disadvantages to the miracle cloud method – Product quality is variable • Team makeup dependent • Team mood/morale dependent (Monday morning car) • Luck dependent – Product is not produced in a repeatable manner – Product is not produced in an efficient manner • Result – Quality low – Customer Satisfaction Low 2005 MAPLD 19 Design Integrity Concepts

How Do We Replace the Miracle Cloud? • • Provide structure to the development effort Evaluate the effort and the product produced Improve the effort and the product Repeat 2005 MAPLD 20 Design Integrity Concepts

Definitions of Importance • From Q 9000 -2000 • Process – A set of interrelated and interacting activities which transforms inputs to outputs [in our case ideas to devices] • Product – The result of a process 2005 MAPLD 21 Design Integrity Concepts

Implications From These Definitions • If we want a consistent product, we must have a consistent process • If we want to improve a product, we must improve the process • If our company has no (or inadequate) process and we must produce a quality product, then we must establish a process [personal responsibility] • Developing, imposing, and improving a process is not an end (in and of itself) it is only a means to an end 2005 MAPLD 22 Design Integrity Concepts

A Model for Discussing the Design Process 2005 MAPLD 23 Design Integrity Concepts

Notes on the Model • Feedback / iteration are not shown for clarity • Model may be recursive – Board development process includes FPGA requirement definition, FPGA development, instantiation, etc. – Board development process includes the FPGA validation product • Successes and failures are cumulative – Good requirements + successful development => successful instantiation – Bad requirements + failed development => failed instantiation • Complexity multiplies – Complex requirements increase design complexity which, in turn, increases verification complexity • Processes are absolute gates to the next stage of development 2005 MAPLD 24 Design Integrity Concepts

Implications From the Model • All processes must be addressed at all levels of design [there are no shortcuts!] – Does not imply same formality at all levels – Does imply same rigor at all levels • Up front work on requirements is essential! – Must provide adequate time and money – Must gain team buy-in to the process* – Benefits compound throughout the rest of the activities • Simplicity is an essential virtue – Complexity inevitably multiplies • A product is not qualified until both verification and validation are complete 2005 MAPLD 25 Design Integrity Concepts

Additional Useful Definitions (courtesy of Q 9000 -2000) • Specification – A document* stating requirements, needs, or expectations that are obligatory • Quality – The degree to which a set of inherent characteristics fulfill requirements • Customer satisfaction – Customer’s perception of the degree to which the customer’s requirements have been fulfilled • Verification – Confirmation, through the provision of objective evidence, that specified requirements have been fulfilled • Validation – Confirmation, through the provision of objective evidence, that the requirements for a specific intended use or application have been fulfilled • Objective evidence – Data supporting the existence or verity of something • Continual Improvement – recurring activity to increase the ability to fulfill requirements • Note the importance of Requirements 2005 MAPLD 26 Design Integrity Concepts

Summary • I have no assurance that my product will have consistent quality without: – Well-defined requirements – A well planned approach to implementing the requirements – A clearly defined plan for verification and validation of the requirements – The ability to improve the process that produces the product • Without quality product, customer satisfaction is impossible • Without customer satisfaction, I won’t work! • Therefore, I must care about ensuring design integrity 2005 MAPLD 27 Design Integrity Concepts