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ConstraintsDescription Power RequirementsThe solar panel must be coupled with a battery to function during night time usage and instances or periods without adequate sunlight. Battery ProtectionThe battery must be protected from deeply discharging and overcharging according to predetermined specifications provided by the manufacturer Output PowerThe unit must be able to output a range of power from 10W to 40W. Up to 5A combined. User InterfaceThe user interface must display when charging station has power available, the user’s remaining charge time, and whether the station is in normal operation or a low power state. Secure EnclosureThe charging station must provide a secure weatherproof enclosure for users to leave a device unattended while charging

CategoryNameDescription EnvironmentalWeatherproofingCharging station must be able to operate in areas where precipitation is likely to occur. Health and SafetyProtectionWires must be properly insulated and the battery must be inside an enclosure.

Charge Controller Battery DC Power DC/AC Inverter AC Power Microcontroller User Interface Database [7] [8] [9] [8] [9]

ProsConsSelection Monocrystalline 10% - 20% More efficient Perform better under low intensity sun light More tolerant to heat Cost :$165 Polycrystalline Just as reliable as Monocrystalline panels Cost $125 Less Efficient Absorbs less sunlight [4]

ProsConsSelection Flooded Offers a higher discharge rate Constant deep discharging Requires ventilation Requires maintenance AGM (Absorbed Glass Mat) Maintenance free Longer life span Operation temperature ranges Doesn’t perform well when constantly deep discharging [3]

ProsConsSelection Pulse Width Modulation(PWM) Inexpensive: $30 Help in extending battery’s life Cost efficient for smaller systems Peak operation with full battery Solar panel & battery voltages must match Maximum Power Point Tracker(MPPT) Operation temperature ranges Offer a higher rate of charge Cost efficient for larger systems Price: $115 [2]

ProsConsSelection Arduino Mega ATmega 2560 Digital and Analog Pins Based on C/C++ Cost: $25 8 KB SRAM No network capability Wi-fi Shield ($80) Raspberry Pi ARM microprocessor core USB outputs Video outputs Network capability Python Higher Power Consumption Only digital pins Cost: $35 [5] [6]

Atmega328 Operating voltage is 1.8 to 5.5 Cheaper than purchasing 3 Analog to Digital Converters Easy to program Dedicated for low level functions

Atmega328 Output Raspberry Pi Output

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January Research February Research (Jack Hatcher Endowment And ECAB) Order Parts Develop Code March Order Remaining Parts Construct Prototype And Test Subsystems April Finalize Coding, Testing, And Constructing Finished Prototype

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