DEVICE PRODUCT DEVELOPMENT
this doc is very much WIP and incomplete_. Notable TODOs:
- Identify items that are particularly collaborative between e.g. ID/ME, EE/FW
- Integrate an OKR framework into project manager role
- More cleanly define product manager and systemeng/techlead activities, right now lumped under project manager
- Break ME/EE stuff out into test/mfg where applicable
- Cleaner break between tech leads p
- Refactor Inputs to map to gates.
- Add algo info
- Add SQA
- Add Quality/Regulatory
- Define _all_ acronyms
- Add "usual problems" section
- etc
- test, regulatory, quality, biostats, hfe, ux
- clin ops
- clin science
Over the years I’ve worked on many development projects, usually of the “let’s commercialize this new technology” sort. No two are completely alike; the relationships between and skills of the team members, the sense of urgency, the market, and of course the product itself all vary from one project to the next.
The main thing common across all of them is that the devices exist to generate data. Since this is common, I want to generalize what I can about these projects through the lens of data.
Functional Roles
Throughout development of a product multiple roles must be filled. In large organizations there could be at least one person (often multiple) assigned to each of these roles. In smaller organizations individuals often take on multiple roles. For example a mechanical engineer may act as a manufacturing engineer or an electrical engineer may act as an algorithm engineer. The possibilities are as variable as the unique experiences of the team at your disposal.
If any of these roles are neglected. The data will suffer.
Management
Product Management (PM)
Responsible for the product vision. Balances what Technical Lead says is doable with what marketing/sales wants.
If neglected, you’ll collect the wrong data.
Technical Lead (TL)
Responsible for overall functional performance. Balances what Product Manager wants with what Industrial Design, Mechanical, Electrical, Firmware, Software says are possible.
If neglected, you won’t be able to collect any data.
Technical Program Manager (TPM)
Responsible for schedule, budget, and other logistics. Balances what Product Manager and Technical Lead want to do with the resources available.
Device
Industrial Design (ID)
Responsible for making the device something people want to use (usually means easy-to-use and attractive). Works closely with Mechanical and Product Management.
If neglected, peple won’t use your device (no data) or they’ll use it wrong (bad data)
MEchanical (ME)
Responsible for making sure parts fit together, sensors are well-packaged can reach what they need, move appropriately, don’t break, and are produced cost-effectively. Works closely with Industrial Design and Electrical.
If neglected the device will be too expensive (no data), unreliable (bad data), or get in the way of the sensors (bad data)
Electrical (EE)
Responsible for making sure the right combination of components are configured in such a way the device has the required “brainpower” and can sense the required phenomena. Works closely with Mechanical and Firmware
If neglected the device will be too expensive (no data), unreliable (bad data), or have poor sensors (bad data)
Firmware (FW)
Responsible for making sure the the code running on the device does what its supposed to do. Works closely with Electrical, Software, and Algorithm. May also work w/ ID re: on-device UI.
If neglected the device will be unreliable (less/bad data)
Interface
Software (SW)
Generally peripheral to device engineering. Most critical device-related responsibilities are the mobile app (works closely with ID) and data infrastructure (works closely with FW/Algo).
Algorithm (Algo)
Responsible for creating algorithms to turn the data from the sensors into a digital biomarker. Works closely with Firmware and Software
Overarching
New Product Introduction (NPI)
Responsible for getting the device built. Works closely with Mechanical, Electrical, and Firmware Engineering
If neglected the device will be too expensive (no data) and ship late (fewer data)
Quality Engineering (QE)
Responsible for ensuring that regulatory requirements are met. Works across with Mechanical, Electrical, Firmware, Algorithm.
Disciplines: A closer look
To engineer a device Mechanical, Electrical, and Firmware engineering are required. Their constitution varies slightly.
Also each may need their own TPM if the team gets large enough.
Firmware
Team Structure
A Firmware team comprises developers, testers, planners (TPM) and a FW lead
FW Lead
Sets the architecture, high-level design, and test strategy. Enables developres to break that architecture down into implementable and testable tasks.
Developers
Implement chunks of the architecture in code and unit tests. Also responsible for building tools/libraries for test development. (e.g. BLE)
Testers
Develop test strategies and protocols. Execute tests based on sysetm requirements. May also build automated integration tests.
Methodology
Its super common in Firmware to use an agile/scrum approach. It comprises the following elements.
Tasks
A “task” is the smallest piece of work that is tracked. Typically estimated in hours (sometimes ‘points’) they usually require from a few hours to 2-3 days of work.
Features (a.k.a. “Stories”)
Phases
What follows is a progression of the levels of maturity a device development project goes through, and the sorts of work that should be done by various roles. Laid out in this manner makes it look deceivingly clean and linear and so it is my hope that the reader uses it as a guide but resists the temptation to follow it too slavishly.
Initiation
Define Business Case
A good business case should provide history and context for support and should conclude that completion of the project is good for the organization.
Define Scope
Describe the high-level goals of the project. Also describe adjacent goals that are explicitly not in the project.
Define Objectives
Describe each objective in detail. Ideally this rolls right into an OKR scheme.
Define Stakeholders
Both internal and external.
Define team
If you’re early on you can get away with a tech lead and a few engineers to start. If the pace is quick you’ll want to make sure you have capability to scale to all the roles above.
Define costs/benefits
- salaries?
- capital expenditure?
- unit costs?
- opportunity costs?
Planning & Requirements
Define the Product, Staffing, and Requirements. Also identify sizeable business opportunities
Inputs
- Product Concept
- Market Research
Work
PM
- Define Total Addressable Market (TAM)
- Identify target audience and what resonates with them
- Make vs buy analysis
- Define User Needs
- DesignToValue assessment? (link)
- Define value proposition
- Define competitive landscape
- Define Volume & Cost Targets
TPM
- Define Budget
- Define Schedule
- Define Responsibilities Staffing
- Identify Key Demos and Integrations
- Identify NPI Support
- Identify Potential IP Issues
- Define Success
TL
- Define deliverables for architecture
- Define product requirements
- Estimate material costs
- Define resources
- Estimate resourcing against schedule
- Assess risks
Gates
- Internally approved product definition
- First draft marketing requirements document
- Product 1-pager
- Rough Schedule
- Buy-in from stakeholders on “project charter”
Architecture
Identify candidate end-to-end systems to meet requirements
Inputs
- Draft concept/MRD
- Rough experience needs & use cases
- Architecture success criteria
Work
TPM
- Draft Program development Plan
- Draft Regulatory Plan
- Create Resource Plan
- Create Communication Plan
- Updated responsibilities/staffing
TL
- Draft PRD (doc)
- Generate and maintain Open Issues List (doc)
- Identify regulatory requirements
ID
- Define User Interaction
- Form Studies
- Proof-of-concept sketches
- Volumetric renderings
ME
- Research state of the art
- Identify Mechanical Engineering risks
- Identify environmental factors
- Define operating ranges
- Identify critical features
- Volumetric study with Electrical Engineering
- Draft Critical Feature Designs
EE
- Research State of the Art
- Identify Electrical Engineering Risks
- Preliminary BOM
- Volumetric study with Mechanical Engineering
- System Block Diagram
- Eval or Bread-boards for risk items
- Component Decision Matrix
- Draft HW/SW Interface Document
FW
- Research state of the art
- Identify SW Risks/constraints
- System Block diagram (FW Architecture)
- Interface defintion (product ecosystem)
- Draft software requirements
Gates
- Documentation of candidate design solutions
- Stakeholder buy-in on design risks
- Stakeholder buy-in on architecture
- Stakeholder buy-in on PRD
- Development Plan (Cost, budget, schedule)
Proof-of-Concept (PoC) Builds
The goal of PoC is to build and test enough variants of high-risk interfaces that the team can downselect to one design concept for each. A good heuristic is Assuming that the concepts selected are no more than three major iterations from a mass-production design.
Inputs
- Draft PRD
- Draft Program Development Plan
- Updated MRD
- System Architecture
- PoC success criteria
Work
TPM
- Update PRD
- Update Regulatory Plan
- Manage/Message Risks
- Manage/Plan demos
ID
- Draft A-surface CAD
- Generate Cosmetic Model
- Update user interaction
ME
- Material/Component Trials
- Risky Critical Feature Trials
- Test Models
- NFF Design/CAD Package
- Generate Initial Mechanical Engineering BOM
- Update Mechanical Engineering Risks
- Draft CM Criteria
- Alpha Development Plan
- Tolerance Analysis (Risky Features)
- Draft Reliability Test Plan w/ Electrical Engineering
EE
- NFF Schematic Layout, Electrical Engineering BOM
- Functional NFF PoC System
- Key Component Selection
- Updated Volumetric Study with Mechanical Engineering
- 100% HW Validation with SW
- HW/SW Integration Test
- Update Electrical Engineering RIsks
- Draft CM Criteria
- Alpha Development Plan
- Draft Regulatory Plan
- Create Experience Metric Model
- Update HW/SW Interface Document
- Draft Reliability Plan with Mechanical Engineering
- Draft Line Test Plan & Limits
FW
- Update/Refine Architecture
- Electrical Engineering Schematic Review
- Prototype (Throw-away) code
- NFF Hardware Validation
- Updated Risks/Constraints
- Development Plan (WBS)
- Unit & Integration Test Plan
- Update Software requirements
Gates
- Proven feasibility of critical components
- Stakeholder buy-in on PoC system
Alpha Build
The Alpha build (sometimes called “E0”, or “Proto”) is the first time the design is built in its intended Form-Factor, or at least very close to it. The mechanical parts are generally OTS, machined, or 3d-printed where possible. A few items might be tooled up. EE boards are generally in the correct form-factor as well.
The parts are built and tested in-house. The purpose is to gain enough confidence in the design to begin the RFQ process with contract manufacturers.
Depending on your quantity and manufacturing resources, you may be able to fold this and the first EV build into a single build.
Inputs
- Updated PRD
- Updated Program Development Plan
- Draft RET Plan
- Updated MRD
- Functional PoC
- Form-Factor & Alpha Success Criteria
Work
TPM
- Updated PRD
- Maintain OIL
- Manage/Message Risks
- Monitor System Integration
- Manage Vendor Relationships
- Mediate ID, Cost, Performance Battles
- Manage/Plan Demos
ID
- Updates to A-Surface CAD
- Draft CMF
- Validate User Interaction
ME
- Final Component Selection
- Update ME BOM
- FF CAD Package
- Functional Form-Factor Prototypes
- Perform high-risk reliability tests
- Update Reliability plan with EE
ME/EE
- Update Reliability Plan
- Update Regulatory Plan
- Identify CM Criteria/Risks
- Estimate Costed BOM
- Test fixture deveopment
EE
- FF Schematic, Layout, EE BOM
- Functional FF Protos
- Validate FF Hardware
- High-risk Reliability/Integration testsing
- Validate User Interaction
- Regulatory High-Risk Pre-Scans
- Update Experience Metric Model
- Update Line Test Plan & Limits
FW
- Update/Refine Architecture
- Key Product Feature Dev (Refactor)
- Boot Loader
- Initial Mfg Tets Suite
- Regulatory Test FW Plan
- Develop Test Tools
- Development Plan
- Update Documentation (APIs, etc.)
- Update Software Requirements
- Update Unit & Integration Test Plan
Gates
- Proven integrated system
- Design ready for quoting
- Stakeholder FF approval
- Locked Regulatory Plan
Request For Quote (RFQ)
Take alpha design and refine it for volume manufacturing
Inputs
- Final PRD
- Final MRD
- CM Short-List for RFQ
Work
TPM
- Orchestrate RFQ Package
- Organize Test Plans (Reliability and Line)
- Mediate Cost vs Performance
- Support IP demands
- Factory Selection
ME
- EVT CAD Package
- Tooling/Fab Strategy
- Restricted Substances Check
- FMEA
ME/EE
- RFQ Documentation packages
- DFx Incorporation
- Updated Costed BOM
- Update CM Criteria/Risks
- Define Assembly Instructions
- Finalize Reliability Plan
- Finalize Line Test Plan
EE
- Vendor Schematic/Design Review
FW
- Finalize Mfg Test Suite
- MFG Test Docs
NPI
- Ramp up
- DFx Input
- Review CM Line Process Plan
- Review Test Plans
- Supply Chain Plan
- Sample Allocation Plan
- NPI Build Plan
Gates
Engineering Validation (EV) Build
This is the usually the first build at the production factory. The parts are made with production processes and the assembly process includes required testing stations
Inputs
- Buld Package
- NPI Build Plan
- Line Test Plan
- RET Plan
- Functional FF Units
- Manufacturing Tests (Firmware)
- Full QA Coverage
- CM Supply Chain Plan
- EVT Success Criteria
Work
TPM
- Mediate Design Transfer
- Manage/Message Risks
ID
- Cosmetic Review
ME
- Production Tooling Review
- DVT CAD Package
- Update ME Risks
ME/EE
- Reliability Results Review
- Assembly Process Review
- Process Capability Review
- Enterprise BOM Control
- Update Risks
- Support Regulatory Testing
EE
- DFX Updates
- Approve Proposed Second-Sources
- Fab and Assembly Docs
FW
- Manufacturing Test Updates
- Line Test Troubleshooting
- Regulatory Test Support
NPI
- Design Ownership Transfer
- Reliability Review
- Qualification DOE
- Draft Line Documentation
- Draft Line Test Coverage & Limits
- Update NPI Build Plan
Gates
- Device is manufacturable
- Device meets regulatory requirements
- Assembly Documentation
- Device meets assembly requirements
Design Validation (DV) Build
Build validated form-factor design in high volume and refine to eliminate design issues
Inputs
- Updated NPI Build Plan
- Updated Line Documentation
- Successful EV Build
- Successful Regulatory Testing
- EVT Yield & Limit Data
- EVT Reliability Results
- Enterprise BOM Control
- NPI Team Ownership
Work
TPM
- Manage Risks
ID
- Cosmetic Review
- Final CMF Tweaks
ME/EE
- Reliability Results Review
- Failure Analysis Assistance
- Design Updates
- Update Risks
EE
- Review Line Limits and Failure Stats
FW
- Manufacturing Test Updates
- Line Test Troubleshooting
NPI
- Monitor Line Data
- Monitor Reliability Results
- Freeze Test Limits
- Qualification DOE
- Update Line Documentation
- Update Line Test Coverage and Limits
- Update NPI Build Plan
Gates
- Manufacturing Process meets QC Criteria
- CMF Lock
Process Validation (PV) Build
Build validated DVT design in high volume to find associated process and capacity issues
Inputs
- Updated NPI Build Plan
- Updated Line Documentation
- Successful DVT Build
- DVT Yield and Limit Data
- DVT Reliability Resutls
Work
TPM
- Manage Risks
ID
- Cosmetic Review
ME/EE
- Reliability Results Review
- Failure Analysis Assistance
- Design Updates
- Update Risks
EE
- Review Line Limits and Failure Stats
FW
- Manufacturing Test Updates
- Line Test Troubleshooting
NPI
- Monitor Line Data
- Monitor Reliability Results
- Qualificication DOE
- Pilot Units
- Update Line Documentation
- Update Line Test Coverage and Limits
- Update NPI Build Plan
Gates
- Process meets capacity and yield requirements for MP
Mass Production (MP) Build
Build Validated PVT design in high volume to find associated process and _capacity issues
Inputs
- Successsful PVT Build
- PVT Yield and Limit Data
- PVT Reliability Results
Work
TPM
- Project Post-Mortem
- Final Documentation
ME/EE
- Final Documentation
FW
- Field Upgrade Development
- Field Upgrade Test Cases
NPI
- Cost-down exercises (Sourcing, design)
- Monitor Line Data
- Monitor Reliability Results
Gates
Manufacturing process continues to meet QC and yield requirements
End-products exhibit acceptable return-rates
###### Functionality is frozen