PRODUCT DESIGN and DEVELOPMENT

Chapter 6: Product Specification

LecturerTetuko Kurniawan

Teaching sourebook:Chapter 6 of Product Design and Development Karl T. Ulrich & Steven D. Eppinger

PRODUCT DEVELOPMENT PROCESS

establishingTarget Specifications:1. Prepare the list of metrics2. Collect competitive benchmarking

information3. Set ideal and marginally acceptable

target value4. Reflect on the results

Set Final Spec.:1. Develop technical models of the product2. Develop a cost model of the product3. Refine the specifications, making trade-

offs where necessary4. Flow down the specifications5. Reflect on the results and the process

What are specifications?

• Product Specification is precise description of what the product has to do.

Customer needs“language of the customer”’Example- Easy to install

Customer needs“language of the customer”’Example- Easy to install

Product specifications“metric” and a valueExample:metric: time required for assembly of fork to the frame. Value: 20 seconds.

Product specifications“metric” and a valueExample:metric: time required for assembly of fork to the frame. Value: 20 seconds.

Customer needCustomer need

Metric and valuesMetric and values

Need - metric Table Need - metric Table

A few guidelines...● Metrics should be complete: all metrics correlate with

satisfaction of need. ● Metrics should be dependent variable.

Dependent: mass of fork vs independent: material of fork. ● Metrics should be practical● Some needs cannot easily be translated into quantifiable

metrics. Example “pride when using the product”● The metric should include popular criteria for comparison

in the marketplace

Collect Competitive Benchmarking Information

Compare all the metrics in competitor products

Time consuming activities

Data from competitors not always true

Compare all the metrics in competitor products

Time consuming activities

Data from competitors not always true

Other format of benchmarking

Dot: customer perception of the relative degree to which their products satisfy their needsNeed more time to collect customer perception data

**** more dots means better satisfaction

● Two types of target values– Ideal values: best result the team could hope for

– Marginally acceptable value: value of the metric that could just barely make the product commercially viable

● Five ways to express:– At least X

– At most X

– Between X and Y

– Exactly X

– A set of discrete values

Set Ideal and Marginally Acceptable Target values

Example

Setting the final Specifications:Develop technical models of the product

Develop a cost model of the productRefine the specifications, making trade-offs where necessary

Flow down the specificationsReflect on the results and the process

(recommended steps)

Develop technical models of the product

● Technical model of a product is a tool for predicting the values of the metrics for a particular set of design decisions → analytical and physical approximations of the product

● This modeling:– Allows prediction if set of spec. is technically feasible by exploring different

combinations of design variables → predict technical performance

– prevents the team from setting a combinations of specifications that cannot be achieved

Input: independent variable

Output: dependent variable

Built and test

Simulation/theory

● Product can be produced at a target cost● Target cost is the manufacturing cost at which

the company and its distribution partners can make adequate profits while still offering the products to the customer at competitive price

● Creating Bill of Material → estimate cost for each part + rough estimate assembly & overhead cost

● Cost model → predict cost performance

Cost Model of the Products

Cost Model of the Products

Competitive map and trad off curves

Competitive map: position the new product relative to the competitionTrade off curves: performance of the product concept for a range of design variables

Set the Final Specification