Eric Hettler - ME William Gallagher - ISE Christopher Mieney - ME Gregory Ryan - ME Joseph Cole - EE FAB AMERICA

Design Review Agenda Project Overview Customer Needs Customer Specifications Concept Development and Proposed Design-Material Delivery Concept Development and Proposed Design-Color Delivery Concept Development and Proposed Design-Curing System Concept Development and Proposed Design-Motion Control Project Plan Risk Assessment

Project Overview open-source architecture Print photo-curable resin Color printing used as a vehicle to demonstrate multi-material print capability

Customer Needs Customer Need #ImportanceDescriptionComments/Status Safety CN1HighContains the UV radiation CN2LowMoving Parts will not hurt the userScrapes, pinching, sharp edges Multicolor/Material CN3HighCapable of printing multi color CN4HighCapable of printing photopolymerCured by UV light Repeatability CN5MedLayer to layer CN6MedPart to part Accuracy CN7MedPosition VariabilityPrint head can retrieve location CN8MedColor Variability mindset CN9HighLow Cost CN10LowGraphical User Interface CN11MedEasy to read User Manual Speed CN12MedPrints relatively quickly CN13HighDoes not take a copious amount of time to cure CN14LowCan be set up quickly and easily Aesthetics CN15MedMachine looks presentable CN16MedOperation is smooth and observable

Engineering Specifications Eng. Spec # ImportanceSourceSpecsDescription Unit of Measure Marginal ValueDesired Value ES1HighCN1Contain the UV radiation% Absorbed at 355 nm%8090 ES2LowCN2 No physical damage to users Opening sizecm^2< 1<.5 ES3HighCN3Can Print MulticolorQuantity of reservoirs#33 ES4HighCN4Can Print PhotopolymerViscosity of epoxycP165 ES5MedCN5Layer to LayerVariance of layer thickness%+/- 5+/- 2 ES6MedCN6Part to PartVariance of part dimensions%+/- 5+/- 2 ES7MedCN7Positional VariabilityToleranceinch ES8MedCN8Color VariabilityPrint Multiple Colors# of colors> 1> 256 ES9HighCN9Low CostStay within Budget$< 3,000< 2,500 ES10LowCN10Graphical User InterfaceSurvey of operators% Approval> 70> 80 ES11MedCN11User ManualSurvey of operators% Approval> 70> 80 ES12MedCN12Print SpeedRate of flow from print headmm^3/sec ES13HighCN13Curing Time Time to cure a given amount of epoxy sec/cm^2< 3< 1 ES14LowCN14Setup Time Time to prepare machine for operation mins< 30< 15 ES15MedCN15MachineSurvey of random people% Approval> 70> 80 ES16MedCN16OperationSurvey of random people% Approval> 70> 80

Systems Overview

WaterClear® Ultra Stereolithography Resin For Solid State (355nm) laser systems Looks like acrylic Feels like ABS

Material Delivery Concepts ABC Ball Point ApproachMicro-Valve Disposable Syringe (control) Selection Criteria DescriptionWeightRatingWeightRatingWeightRatingWeight CostLow cost10% Speed Speed at which the print head dispenses epoxy 15% PrecisionDroplet size consistency20% ServiceabilityEase of maintenance15% Feasibility How possible it is to implement the system 25% Controllability Ability to control the motor with the given software 15% Total Score Rank Continue? No Yes No Material Delivery Concept Selection

Material Delivery Proposed Design: material delivery nozzles Tube ID:.033”-.002”Proposed Design: Micro Valves Photos From The Lee Company

Material Delivery Nozzle size can range from 30ga. to 14ga. (.006”-.069” inner dia.) 30 gauge 0.006" (0.229mm) Inside diameter REG/Photographers_Formulary_09_0350_Micro_Mixer_Measuring_Syringe_12ml.html

Color Delivery Concept Selection

Color Delivery Concepts Pre-Colored Epoxy Reservoirs Deposition Mixing Process Deposition Carrier Stream Dye/Pigment Reservoirs Mixing Process Epoxy Reservoir Carrier Stream Dye/Pigment Reservoirs Mixing Process Proposed Design: Pre-Colored Resin Design Alternatives: Color Injection Deposition Mixing Process

Motion Control Concepts AB Servo MotorStepper Motor (Control) Selection CriteriaDescriptionWeightRatingWeightRatingWeight CostLow Cost20% Speed How fast the print carriage moves 10% Accuracy Ability to move to a given position 30% SizePhysical volume10% Ease of Control Ability to control the motor with the given software 15% Range of MotionAchievable positions15% Total Score Rank 2 1 Continue? No Yes Motion Control Concept Selection

Motion Control Assessment E35 H4B Used for the x and y axis inches (.0158mm) per step

Motion Control Stepper Motor Servo Motor

Curing Concepts ABCD Overhead Light Mini-Halogen (offset method) LED (offset method) Laser (ring method) Selection CriteriaDescriptionWeight RatingWeightRatingWeightRatingWeightRatingWeight CostLow cost10% Speed Speed at which the light cures the epoxy 20% Feasibility How possible it is to implement the system 25% Thoroughness Its ability to cure completely 25% Controllability Ability to control the motor with the given software 20% Total Score Rank Continue? Yes No Curing System Concept Selection

Potential Light Sources – LED’s Led Spot Cure Linear LED Array -Current LED control boards frequency output is too high (365nm.) Resin cures at 355nm. -Too expensive, $1650 -Fast cure times, 0.5 seconds -Cost is approx. $400

Overhead Lights Florescent UV Advantages Inexpensive, ~ $30 Ease of implementation Florescent UV Drawbacks Low Power, ~ 40 W Greater distance to part yields longer cure times UV Flood Lamp Advantages High power, up to 400 W Cure Times 5-30 sec UV Flood Lamp Disadvantages Poor irradiance at 355nm

Potential Light Sources - Laser -Current platform is too large for existing architecture.

Potential Light Sources – Mini Halogen Benefits -Small Size, bulb diameters ~ 5mm -Inexpensive, $15-75 Drawbacks -High operating temperature, > 250 C -Output at required wavelength somewhat low 355nm = 3.05E-3 (W/cm^2) Cure Time Estimate

Curing System – Light Delivery Concepts

Project Plan

Risks