Product development process - schedule illustration
				Duration in weeks
	Milestone		Complexity ->	Low	Medium	High
	RD	Requirements Defined phase		1	1	3
			Commercial specification (includes info on target destination markets) to be translated into technical requirements such as applicable regulatory standards & their parameters, customer-specified quality standards, commercial requirements such as limits for noise, cost & mass limits etc.
	CS	Concept Selection phase		0	3	5
		Feasibility assessment		0	1	2
			May be required if product involves new or unproven technology.
			Also time to do some engineering feasibility work such as basic thermal / structural / tolerance studies
		Concept Selection		0	2	3
			A number of concepts would be generated and short-listed to 3-5.
			May require the manufacture of "appearance" block models etc. Particularly applicable if Industrial Design is required.
			Would need to show how visual language works in different deployment / mounting scenarios if relevant.
	CR	Concept Ready phase		1	2	4
			Chosen concept is developed further and all aspects considered - industrial design, cost, manufacturability, tolerancing etc.
			Would usually involve detailed thermal management study.
			At this point the chosen concept must show how all specified requirements will be met.
	FA	Functional Agreement phase		2	5	8
			Detail design commences after this milestone.
			The first deliverables after Concept Ready (CR) are the PCB constraints files to enable layout to commence.	1	2	3
			Detail design continues to a point whereby 3D files are available for build	1	3	5
	SR	Sample Review phase		5	10	15
		Prototype build
			May require the procurement of special materials (place orders early at risk).	0	1	2
			Likely to include the manufacture of fabricated sheet metal parts, machined components, rapid prototyped plastic parts, dummy PCBs, labels & cables.	4	5	6
			May need to add 1-2 weeks for surface treatments & painting	0	1	2
		Fit, Form & Function inspection		0	0	1
		Prototype test
			May wish to perform some basic confidence tests: Airflow / thermal, Shock / Vibration, EMC etc.	0	2	3
		Sample Review
			Milestone at which prototype build & test results are assessed.	1	1	1
	PA	Physical Agreement phase		1	2	3
	MR	Manufacture Ready phase		1	2	3
			Preparation of Manufacturing Documentation
			> piece-part drawings
			> assembly documentation
			> stock lists / Bill of Materials (BOMs)
		Production tooling		1	6	14
			Can range from "soft" tooling (programming), through purchase of punches to full tooling for castings or plastic injections mouldings.
			Typical duration for plastic Injection Mouldings
		First-off Sample build		4	5	6
		Assembly & functional test		1	1	2
		Regulatory test & approval		6	8	12
			Minimum regulatory test, e.g. Safety, EMC
			Typical duration in weeks ->	23	45	75