Solar Powered Tracker and Charging Device Sponsored by

Solar Powered Tracker and Charging Device Sponsored by: Progress Energy Group 12: Diijon Gumbs James Lillie Kaniel Martin

Goals and Objectives To build a mobile device to track sunlight and use it for conversion to energy for charging batteries (car and normal sized battery). � Needs to be cost efficient � Needs to be able withstand different types of weather conditions. � Track the most amount of sunlight through actuation. �

Specifications and Requirements � � Solar panels ◦ Weather Resistant ◦ Produce 40 W of power ◦ Have 50% efficiency Frame ◦ Weather Resistant ◦ 360 degree horizontal rotation ◦ 120 degrees vertical rotation ◦ Total Weight No larger than 30 pounds ◦ Rotating Frame No larger than 15 pounds ◦ Dissipate heat Voltage Regulator ◦ Used to charge 5 -12 Volt batteries ◦ Have about 85% power efficiency Stepper Motors ◦ Use 0. 5 -1. 5 amps ◦ Can freely move 5 pounds

Specifications and Requirements Continued � Microcontroller � Batteries � Voltage Sensors � Display ◦ ◦ Can at least receive 8 inputs Has at least 10 output ports Can handle both analog and digital I/O Has Pulse Width Modulation ◦ Rechargeable ◦ 15 -20 V ◦ Can read voltage from 0. 1 - 50 V ◦ Can display our four output criteria ◦ Can support at least a 5 V input � Servo Motor ◦ Operates on 5 V ◦ 100 degree turning radius

Block Diagram of Design Solar Panels Batteries Regulator LCD Display Photo Sensors Voltage Sensors Microcontroller Motor Controller Motors

Solar Panels, Microcontroller, Voltage Regulator, Batteries Kaniel Martin

Arduino Mega 2560 � 5 V operating voltage � 6 -20 V input � 54 digital I/O pins � 14 PWM outputs � 16 analog Input Pins � 256 KB Flash Memory � 8 KB SRAM � 16 MHz Clock Speed

BSP 10 Solar Panel Characteristics Dimensions Weight Typical Data at STC (Standard Test Conditions) 16. 5 in 10. 7 in 1. 31 in 4. 2 lbs Rated Power Pr 10 W Peak Power Pmpp 10 W Peak Power Voltage Vmpp 17. 3 V Peak Power Current Impp . 58 A Open Circuit Voltage Voc 21. 3 V Short Circuit Current Isc . 66 A

Solar Panel Diagram

LM 358 Voltage Regulator • 35 Max Voltage

Batteries � 19 V Battery used to power the board, and LCD � 16 V Battery used to power the motors � 12 V and AA Batteries used for charging

Alkaline Batteries �Rechargeable � 80% efficiency �Up to 50 times the lifetime of the non-rechargeable variety � 50 – 500 cycles �Easy to predict charge �Non Rechargeable � 95% efficiency �Less than 5 year lifespan �Harmful to the environment �Cheap!!

Nickel Cadmium � 70%-90% efficient � Lasts up to 5 years � 1500 cycles � Charge rate of C/10 � Lose charge quickly � Toxic! � Average Cost

Lithium Ion � High initial voltage � Have a high charge level � Become very hot � Excellent performance initially but declines with time. � Very expensive � 1200 cycles � 2 -3 years � 5%- 10% discharge rate

Lead Acid Batteries � 70% – 80% efficient � Lasts 5 -8 years � 500 -800 cycles � Charge Rate of C/8 � Low Cost � Easily Recycled � Large Array of sizes and voltage levels

Problems � Deciding on whether to use one battery to power the whole project, or to designate a battery for each component. � How to deal with the major fluxuations in voltage from sunlight to the circuit design and overall efficiency. � Not only learning more about the different programming codes needed for our design, but the integration of them as well.

LCD Display, Solar Sensors, Voltage Sensors Diijon Gumbs

LCD Display �We need a display to show the proper criteria in relation to the project. �These criteria include: power efficiency, current, voltage, and battery life. �This criteria must be produced on the display through a percentage or as a unit of measurement. �Memory storage will be an important element in determining what type of display chosen.

Hitachi HD 44780 Display � � � Usage of ASCII symbols through binary to read to the display. Cheap in cost Dimensions: 98. 0 x 60. 0 x 15. 0 mm 16 ports to be used Components ◦ 20 characters by 4 line display ◦ White characters with a blue background and backlight display ◦ 7 pin GPIO pin usage for 4 -bit mode and 11 pin GPIO pin usage for 8 -bit mode ◦ 5 V DC operation ◦ Wide viewing angle and high contrast ◦ +5 V DC LED backlight

HD 44780 LCD Display

HD 44780 LCD Display � For this project we will be only using a limited amount of ports and not all of them for our displaying of data. � Will be employing 4 -bit mode operation � 16 -bit male header needs to be put on through a soldering process before being used with breadboard.

Viewing our results on LCD Display �Backlight will be incorporated when weather conditions hinder viewing ability. �We need to also change the contrast by using a 10 k potentiometer connected to the contrast port (port 3).

Circuit Schematic

Solar Sensing � Sense how much sunlight is being shone. � Usually most solar sensing is used through the use of photodiodes or photoresistors. � Must be used through devising a circuit.

Photoresistors �Same as photodiodes except they don’t react to sunlight well. �Use simple voltage divider circuit to get readings. �Best decision when it comes to our project. �Looked into the VT 400 Perkin Elmer series. �Three main types: Indium Antimonide, Silicon, and Cadmium Sulfide.

Photoresistors Continued � � � Our choice was the Cadmium Sulfide type photoresistor from Adafruit (light: 5 -10 K; dark: 200 K). Will be using with a 1 K resistor to realize voltage reading circuit with the 5 V input connected to microcontroller port. Other portion will be connected to analog pin on arduino board. Can use a 10 K resistor instead, but it will hurt our readings at bright levels of light.

Voltage Sensing � Looked into many types of panel sensors. � One approach: we were looking into using a voltmeter to incorporate into our finalized circuit through the soldering of the contacts onto a finalized circuit. � Final decision: ◦ Simple voltage divider circuit to read the voltage as we used for the light sensing. ◦ similar to photoresistor circuit

Circuit Implementation � Using a breadboard kit to conglomerate LCD Display, voltage dividers with the photoresistors will make up our circuit.

Problems LCD Display ◦ Have to learn more about the use of the codes for the ASCII characters (display). ◦ Looking into how to incorporate display with the main microcontroller to show the accuracy of the results. � Solar Sensor (Photoresistor) ◦ Finding out if the resistor value chosen will indeed show the brightness of the light or miscalculate the results. � Voltage Sensor ◦ How to make sure the readings were read precisely with accuracy (noise). �

Frame, Motors, & Motor Controllers James Lillie

Frame Required to house electrical components as well as allow mounting locations for solar panels Allows two Panels to be mounted one facing up one facing down Has reflective surface for downward facing solar panel Allows for a locking mechanisms Water Resistant

Panel Rotation 360 Degrees of Horizontal Rotation 120 Degrees of Vertical Rotation DC Motors, Stepper Motors, Servos, Linear Actuators Gear Reducing Ratio for higher torque Accurate Rotational Speed

Frame Side View

Frame Top View

Sunlight Sensor Design

Servo Motor Used as a locking mechanism Can operate off of the Arduino Mega 2560 Can operate on 5 V power source Rotation Range of at least 60 degrees

Servo Motor Comparison Servo Motor Range Operating Voltage Price Hitec HS 311 Servo Standard 90 degrees 4. 8 -6 V $8. 99 Hitec HS-322 HD standard hobby servo Hitec HS-422 standard hobby servo 100 -200 degrees 60 -200 degrees 4. 8 -6 V $9. 99 $12. 99

Hitec 322 Standard Servo Motor Torque: 41. 66 51. 38 oz*in Voltage: 4. 8 V - 6 V Turning Range: 100200 Degrees

Stepper Motor � Needed to turn frame. � Low power consumption (less than 2 amps) � High Torque � Able to output enough force to rotate a static 15 lb disk

Stepper Motor Comparison Stepper Motor Holding Torque Current Rating Torque Price NEMA-23 12. 5 Kg-cm Bipolar 76 mm Stepper 2. 2 A $31. 20 M-200 ROB 09238 0. 28 -0. 33 A $14. 95 2. 5 A $51. 65 2. 4 kg*cm NEMA-17 30 Kg-cm Bipolar 5. 18: 1 Planetary Gearbox

Bipolar Stepper Motor Step Angle: 1. 8 degrees 2 Phase Rated Voltage 12 -15. 4 Volts Rated Current. 28 -. 33 Amps Holding Torque 2. 4 kg*cm Detent Torque 120 g*cm

Motor Controller Needed to drive two stepper motors Voltage rating of at least 16 volts Easily interfaced with micro-controller Has quarter, half, and full step capabilites Has Sleep Mode for Power Saving

Motor Controller Comparison Stepper Motor Controller Current Supply Voltage Supply Number Of Motors Driven Price Easy. Driver 150 v 4 750 m. A 7 -30 V 1 $14. 95 L 298 5 -46 V 1 $23. 50 2 A

Eazy Stepper V 4 Drives one Bipolar Stepper Motor Compatible with 4, 6, or 8 wire Motors Power Supply Range of 7 -30 Volts Adjustable Current From 0. 15 -0. 75 Amps Sleep Mode

Motor Controller Circuit

Problems Frame Rotating Location Ø Frame cannot rotate more than 360 degrees to stop the tangling of wires.

Progress Chart Solar Power Tracking Device Research Design Parts Acquired Parts Built Testing Total Progress 0 20 40 60 80 100

Budget Components Prices Microcontroller $72, 00 Motor Controller x 2 $35. 50 Stepper Motor x 2 $33. 50 LCD Display $25. 00 Photoresistors $12. 00 Circuit Board Kit $26. 00 Batteries TBD ~ $60. 00 Solar Panels TBD ~ $240. 00 Misc. (resistors, wires, etc. ) TBD ~ $20. 00 Frame Materials TBD ~ $100. 00 Estimated Total (subject to change) $626. 00