BAB 11 : Prototyping

Dira Ernawati, ST. MT - P3 2 Prototyping An approximation of the product along one or more dimensions of interest –Industrial designers  concepts –Engineers  a design –Software developers  a programming concept

Dira Ernawati, ST. MT - P3 3 Types –Analytical vs Physical Analytical: Intangible; mathematical; investigate interesting aspects Physical: Tangible; approximate the product or parts of the product –Comprehensive vs Focused Comprehensive: Full-scale, fully operational Focused: Implement one or a few attributes of the model; often “looks like” or “works like”

Dira Ernawati, ST. MT - P3 4 Physical Comprehensive Focused Analytical Alpha Prototype Final Product Beta Prototype Not Generally Feasible Equation modeling of a part SLT model of a part Machined model of a subassembly FEA modeling of a part

Dira Ernawati, ST. MT - P3 5 What are prototypes used for? –Learning Will it work? Does it meet the customer’s needs? –Communication Look and feel For management, vendors, extended team, investors –Integration Do parts, subsystems, systems work together? –Milestones

Dira Ernawati, ST. MT - P3 6 Principles –Analytical – generally more flexible than physical –Physical – detect unanticipated phenomena –Prototypes can reduce iteration process –Prototypes may expedite other development stages –Prototypes may restructure task dependencies

Dira Ernawati, ST. MT - P3 7 Example: Physical Prototype Student Project: Automatic CD Changer

Dira Ernawati, ST. MT - P3 8 Modern Technologies –Computer modeling 3D modeling: shape, size, fit, kinematics Finite Element: stress, strain, deflection –Free-form fabrication Rapid prototyping: Stereolithography

Dira Ernawati, ST. MT - P3 9 Kinematics

10 Finite Element Analysis

Dira Ernawati, ST. MT - P3 11 Finite Element Analysis

Dira Ernawati, ST. MT - P3 12 Rapid Prototyping

Dira Ernawati, ST. MT - P3 13 Planning process –Define the purpose Learning, communication, integration, milestone –Establish the level of approximation Analytical/physical; focused/comprehensive –Outline an experimental plan –Create a schedule for procurement, construction, and test

Dira Ernawati, ST. MT - P3 14 Milestone prototypes –Provide tangible goals –Demonstrate progress –Enforce the schedule

Dira Ernawati, ST. MT - P3 15 Types of milestone prototypes –Alpha Similar shapes/materials; often different production processes Used to assess if product works as intended –Beta Use production processes, assemble by hand Used to assess reliability; identify bugs May be given to customers –Preproduction First products of entire production process Provide test product Validate production process