1. Alternative Power Source for Dental Hygiene Device Nizar Almansouri Ningbiao Jiang Francisco Heath Jin Niu Jiaqi Xie Concept Generation and Selection

2. Contents of Presentation 1 1. Problem Statement 2. Design Summaries 3. Criteria Comparisons 4. Gantt Chart 5. Conclusion 6. References

3. Problem Statement NAU Department of Dental Hygiene  Humanitarian work in remote areas  No electricity available to power Wig-L-Bug 2

4. Possible Solutions  Solar + Battery  Manual Charger + Battery  Battery Only 3

5. Solar + Battery  Flexible Solar Panel, 2 square meters  Battery and Inverter connected in Parallel  Calculations based on average insolation in December 4

6. Component Size(in)Weight(lb)Cost($)Quantity Total Cost($) Solar Charger 8.5×14.53.29401 24V Inverter Modified Sinewave 5×2.25×7.254.2401 Cable360.8301 Total14.5×8.5×58.2 1010 5 Detail of Solar Battery Method

7. Manual Generator + Battery 6 × A Bicycle style crank will turn an alternator with a belt or chain drive Off-the-shelf bicycle parts will ensure good efficiency and reliability 100 watts of input at the pedals is a sustainable level for average college student

8. Manual Generator + Battery Details 7 PartCost($)Weight (lb) Alternator758 Battery1001 Inverter501 Frame758 Gears, Cranks, Pulleys, etc 1505 Wiring, electronics, etc501 TOTAL50024

9. Battery Only 8 Battery Cell Details Cell Voltage3.7 V Capacity120 Watt hours Charge Current1.8 Amps Discharge Current1.2 Amps Weight5 lbs

10. Battery Only 9 PartsQuantityPrice ($)Subtotal ($) Battery460240 Charger130 Inverter120 Frame120 Total310

11. Raw Comparison 10 SolarGeneratorBattery Uninterrupted Power (% Down Time)2000 Cost ($)1000450300 Weight (lb)1225 Life Span (hours)5001000500 Size (Within 56 x 45 x 25 cm)yes Peak Output (watts)120400250

12. Normalized Data 9 SolarGeneratorBattery Uninterrupted Power (% Down Time)010 Cost ($)05.57 Weight (kg)1055 Life Span (hours)5510

13. Weighted Comparison 10 Uninterrupted Power Cost Weight Lifespan Raw Total Normalized Total Uninterupted Power123390.425 Cost0.51326.50.307 Weight0.33 123.660.173 Lifespan0.330.20.512.030.096 Certain Criteria, like size and peak output, either meet constraints or they don’t. Others, like weight and cost, should be as low as possible

14. Weighted Criteria 11 SolarGeneratorBattery Uninterrupted Power (% Down Time)04.25 Cost ($)01.68852.149 Weight (kg)1.730.865 Life Span (hours)0.48 0.96 Total (Higher is Better)2.217.28358.224

15. Gantt Charts 12

16. Summary 13 Problem Statement Design Concepts Comparison Design Selection Gantt Chart

17. References  www.solar-electric.com  www.batteryspace.com  www.autozone.com/autozone/parts/Alternator  www.weatherbase.com/weather 14