P15503 Electrophotographic Cascade Test Rig System Level Design Review Dalton MeadBridget Kearney Mike WarrenRuishi Shen Tom WossnerZack Foggetti

Overview ●Background ●Where We Left You Last - Week 3 Action Items ●System Analysis ○Updated CR/ER & HOQ ○Functional Decomposition ●Architecture Development ○Concept Development ○Morph Chart & Pugh Charts ○Concept Selection ●Feasibility Analysis ○Benchmarking ○Questions ●System Architecture ●System Proposal ●Risk Assessment ●Test Plan ●Project Plan ●Questions

Brief Background Electrophotography - How a laser printer works

Action Items from Week 3 Review 1. Create risk assessment spreadsheet 2. Finalize ER specs 3. Continue benchmarking 4. Find video or other, new, better ways to define electrophotography 5. See device in action/get our hands on it

System Analysis - Updated HOQ

System Analysis - Functional Decomp.

-Brainstorming Process -Selection Criteria: - Is safe -Total costs is less than $5,000 -Contains particles easily -Processes can be automated -Development zone is easily accessible -EM field is easy to adjust -Flow rate is accurate -Prevents particles clumping -Is able to recirculate particles easily -Is doable within two semesters -Is able to hold constant flow rate Architecture Development -Concept Development

Architecture Development - Morph Chart

Architecture Development -Select Alternative ●Accept Charged Particles - Load Cartridge + Funnel o Advantages  Self-contained  Controls flow  Similar to current InkJet printers  Feasible/ simple design  Reusable o Disadvantages  Particles manually loaded  May lose particles to the air

Architecture Development -Select Alternative ●Initiate & Stop Flow - Aperture o Advantages  Precision control  Programmable  Cheap  Readily available / market variety o Disadvantages  Potentially accumulate particles in mechanism

●Move Particles - Rely on Gravity o Advantages  Predictable & Reliable  System does not break o Disadvantages  Requires additional mechanism to adjust flow Architecture Development -Select Alternative

●Attract/Repel Particles - Charged Plates o Advantages  Creates capacitor  Predictable and uniform electric field o Disadvantages  The effect of Paschen’s Law Architecture Development -Select Alternative

●Collect Excess Particles - Container o Advantages  Simple, cheap, readily available  Choice of size, material, and shape  Reliable o Disadvantages  May lose particles to the air Architecture Development -Select Alternative

●Recirculate Particles - Vacuum Pump o Advantages  Self-contained  Automated  Easy to use  Readily available o Disadvantages  May require maintenance Architecture Development -Select Alternative

●Contain Particles Throughout - Exhaust Hood o Advantages  Currently in place  Reliable  Easy to use o Disadvantages  Airborne particles are lost  Limits portability Architecture Development -Select Alternative

●Allow Inspection of Results & Allow Cleaning - Removable Develop Zone o Advantages  Allows plates to be replaced  Easy access to development zone  Allows for different methods of cleaning o Disadvantages  May disturb particle flow path  Requires user intervention Architecture Development -Select Alternative

●Prevent Particle Clumping - Vibration Mechanism o Advantages  Constant / Continuous  Adjustable  Low Power Consumption o Disadvantages  More likely to malfunction Architecture Development -Select Alternative

Architecture Development -Pugh Chart Example

Architecture Development -Pugh Chart Summary

FunctionConcept Selection Accept Charged ParticlesLoad Cartridge Move ParticlesGravity Initiate and Stop FlowAperture Attract/Repel ParticlesCharged plates Collect Excess ParticlesContainer Recirculate ParticlesVacuum/Pump Contain Particles ThroughoutExhaust hood Allow Inspection of ResultsRemovable development zone Allow CleaningRemovable development zone Prevent Particles from ClumpingVibration Architecture Development -Concept Selection

Feasibility Analysis - Benchmarking

Feasibility Analysis - Questions -- How does Paschen breakdown affect our system? For this design we will be implementing a parallel-plate capacitor in order to create an electric field. Paschen’s Law describes the voltage necessary to create an electric arc relating to the pressure and gap length between the two parallel plates. -- What is the relationship between arc flash distance and voltage? – Max voltage at given gap distance: – For 50 microns, 515V; for 100 microns, 786V -- Do charged particles flow easier on conductive or insulating materials? – Confirmed by basic electrophysics

-- Is the proposal of using carrier particles to flow the testing particles feasible? If yes, what are the potential medium particles that are able to carry the particles through? – Feasibility of carrier particles depends on the type of testing particles chosen Feasibility Analysis - Questions

What is the function of the second grounded plate? - Safety? - Discharge excess particles? - Just need to create a bias to attract/repel particles as well as ground the surrounding area Existing Unit Desired Design with removable inserts + + -

Risk Assessment - Technical Risks

Risk Assessment - Project Risks

Test Plan

System Architecture ●Power Supply powers: ○Vibration ○Aperture ○Vacuum Pump ○Charged Plates ●Some components have multiple purposes

System Proposal - Rough Sketch

System Proposal - What’s Next? ●Subsystem Design o Benchmark  Are there other systems similar to our subsystem?  Granular Particle Flow Research o Brainstorm o Rough sketches of subsystems  Feasible ways of acquisition ●Updated/maintain current documents (ERs, HOQ, etc)

Project Plan - What have we done?

Project Plan - What’s next?

Questions We have some too...