Jason Andrews Tyler Burns Maxamillion McMahon Nicolas Reginelli Tyler Schmidt Anna Sementilli Guide: Gerry Garavuso Customer: B9 Plastics

Agenda Project Description Requirements Summary Concept and Design Summary System Architecture Competitive Advantage Testing Results Project Evaluation Recommendations for future work Lessons Learned

Project Description The goal of this project is to improve B9 Plastic’s Better Water Maker. The Better Water Maker works by reducing the number of dangerous waterborne microbes via the use of a UV bulb. Two different designs have been tried in the past, with the current version utilizing a hand crank flywheel as a method of mechanical power generation. The major goal is to design the power system so that it generates the required power with less human effort. The current UV treatment process must not be altered.

Requirements Summary Engineering Requirement DescriptionMetricTarget Value Marginal Value ER1Power GeneratedPower (V/A/W) 12/2.5/17+3/-0 ER2Training TimeTime (minutes) ER3Installation TimeTime (minutes) 90+/- 30 ER4Effort RequiredCO2 L/Min.9-.9 ER5Number of Installers Required # People11 or 2 ER6Unit LifeLife of Parts (Yrs) ER7Electrical Protection Voltage (V), Current (A) 25/3+0/-3

Concept and Design Summary Began with: Plywood Stepped gear box Moved to: Custom gear for correct ratio Solid AL plate Ended with: Static line for pulley Sprocket and chain system

Concept and Design Summary Final Design: Ratio of ~15 through the use of sprockets Turned out to be a little unbalanced Gears… Heat, friction, stretch = energy loss Improvements: In need of a lighter, cheaper redesign Longer base supports Sprocket & chain connected to pedals Cover for safety Alternative way to hold yourself up Some adjustability

Concept and Design Con’t Accomplished: Speed to create power Working prototype Lessons Learned: Design early, allow for time for redesigns Design with assembly in mind Models can be misleading Missed the mark: Cost more than anticipated Some parts showed extreme wear characteristics Safety concerns regarding sprockets Loud noise the prototype makes while operated isn’t pleasant

System Architecture

Competitive Advantage Design chosen due to increased efficiency with use of leg muscle vs arm muscle Standing concept allows use of full body weight Stepping is a more natural motion Allows for a high gear ratio, reducing total work and lactic acid build up

Testing Results-Power Generated Motor Output- 18.4V,2.9A,53W Buck Converter Output- 15V,2.9A,43.5W

Testing Results-Electrical Protection 3A fuse failed (as expected) with a 4.5Ω load at 15V (3.33A) Max voltage is limited to 25V by a capacitor in the Buck Converter The UPS system also has a 3A fuse and the components can handle 40V

Testing Results Hand Crank-max CO2=.85(L/m) Treadle System- max CO2=1.42(L/m) 2.5 steps/second.48 Gal/Min Ramp up to required SPS Pump Delay Pumping Water

Project Evaluation Electrical Power generated was satisfied with 1 motor generating ~18.4V/2.9A/53W. Electrical protection put in place to protect circuitry against a 3A surge in current with buck converter regulating voltage to 14.8V. Battery Management System added to compensate for non-periodic motion of motors and so users will not exert energy for 10 seconds to power on light. System was designed to charge at 15V and to trickle charge at 12V.

Project Evaluation Mechanical Treadle system designed to take advantage of leg strength and body weight. Easier to sustain a constant motion as compared to hand crank. Step rate: 2.53 steps/sec which is at a faster pace than what was designed for. Add flywheel to keep motion constant and reduce step rate. Pulley identified as the failure point of the system. Plastic coated steel cable or spring/bungee pedal return system could be a solution. System could be too complex for people in the third world to assemble properly

Engineering Requirement DescriptionMetric Target Value Marginal Value Actual Performance Rating Was the requirement satisfied? ER1Power Generated Power (V/A/W) 12/2.5/17+3/-0 Power generated was satisfied by generating ~18.4V/2.9A/53W Yes ER2Training Time Time (minutes) Not formally tested for but observed during Imagine; determined that the training time for a child to use the system is <20 minutes Yes ER3Installation Time Time (minutes) 90+/- 30 System could be too complex for people in the third world to assemble properly No ER4Effort RequiredCO2 L/Min.9-.9 Step rate: 2.53 steps/sec which is at a faster pace than what was designed for; Hand crank requires less effort No ER5 Number of Installers Required # People11 or 2 Because of the weight of the system and the complexity, more than 1 installer will be required No ER6Unit Life Life of Parts (Yrs) Pulley identified as the failure point of the system No ER7Electrical Protection Voltage (V), Current (A) 25/3+0/-3 Electrical protection put in place to protect circuitry against a 3A surge in current with buck converter regulating voltage to 14.8V Yes

Schedule and Budget Budget: $1,000 Actual Spending: $940 Project Plan: We fell behind at times during the year but it came together in the end Things left to do: Finalize Paper Final Review Final Peer Reviews Update Edge

Recommendations for future work Weight reduction would be a great way to improve this design Experiment with wrapping rope around the shaft Add flywheel to help reduce the required step rate Simplify amount of parts in product Include stronger pulley/better pedal return system PCB layout for UPS system

Lessons Learned Communication: External (customer) and internal (project team) communication should be more frequent and consistent. Have written agreements for decisions and goals. Planning: Plans constantly change and evolve. Tasks like testing the system will often take longer than anticipated and may introduce issues that further extend timelines. Risks: Discover as many risks as you can. Make sure you account for a lot possibilities, from very likely situations to those you’d never expect to occur. Execution: Teamwork is essential. Share roles and split up work to get things done faster and more efficiently.

Questions?