E-Goat Robotic Solar Farm Grass Cutting System Department of Electrical Engineering and Computer Science University of Central Florida Dr. Lei Wei & Dr. Samuel Richie Sponsors: OUC & Duke Energy April 21, 2020 Senior Design II Group 26 Steven Cheney Computer Engineer Jordan Germinal Computer Engineer Eduardo Guevara Computer Engineer Davis Rollman Computer Science Jonathan Smith Electrical Engineer Table of Contents 1 Executive Summary ...................................................................................... 1 2 Project Description ........................................................................................ 3 2.1 Project Motivation .................................................................................. 3 2.2 Goals ..................................................................................................... 4 2.3 Existing Projects and Products .............................................................. 4 2.4 Articulated Autonomous AI-Assisted Solar Farm Grass Cutter .............. 4 Husqvarna Auto Mower Series ......................................................... 6 iRobot Terra t7 Robot Mower ........................................................... 7 Existing Rover Location and Navigation Technology ........................ 8 2.5 Engineering Specifications ..................................................................... 9 Customer Specifications & Constraints .......................................... 10 Requirement Specifications ............................................................ 12 Team and Product Constraints ....................................................... 13 2.6 House of Quality .................................................................................. 14 2.7 High Level Control Scheme ................................................................. 16 3 Applicable Standards & Design Constraints ................................................ 17 3.1 Applicable Standards ........................................................................... 17 Serial Communication Standard ..................................................... 17 Surface Mount Package Standards ................................................ 21 IEEE Wireless Standards ............................................................... 21 Economic Constraints ..................................................................... 22 Environmental Constraints .............................................................. 22 Social Constraints ........................................................................... 23 Political Constraints ........................................................................ 23 ii Ethical Constraints .......................................................................... 23 Health and Safety Constraints ........................................................ 24 Time Constraints ............................................................................. 25 Testing/Presentation Constraints .................................................... 25 4 Research ..................................................................................................... 27 4.1 Relevant Technologies ......................................................................... 27 Motors ............................................................................................. 27 Power .............................................................................................. 29 Single Board Computer ................................................................... 30 4.2 Microcontroller Control Board ............................................................... 46 Microcontroller Overview ................................................................ 46 Microcontroller Need ....................................................................... 46 Microcontroller Board Options ........................................................ 47 Microcontroller Board Comparisons ................................................ 49 Microcontroller Selection ................................................................. 50 4.3 Obstacle Avoidance Sensors ............................................................... 51 Lidar ................................................................................................ 52 Camera ........................................................................................... 52 4.4 PCB ...................................................................................................... 59 PCB Software ................................................................................. 59 PCB Sourcing ................................................................................. 60 Motor Driver .................................................................................... 61 Voltage Regulator ........................................................................... 61 Remote Relay ................................................................................. 62 4.5 Navigation Sensors .............................................................................. 63 Boundary Wire ................................................................................ 64 Boundary Wire Part Selection ......................................................... 65 iii Localization Technology ................................................................. 66 Localization Technology Part Selection .......................................... 69 4.6 Computer Science and Computer Vision ............................................. 72 Board Selection .............................................................................. 72 Programming Languages ............................................................... 73 Gazebo Simulation ......................................................................... 75 Edge Detection ............................................................................... 76 SLAM Techniques .......................................................................... 79 Reduction of the problem ................................................................ 79 Mobile App ...................................................................................... 81 React Native ................................................................................... 82 4.7 Wireless Communications.................................................................... 83 Bluetooth ........................................................................................ 83 Radio Frequency ............................................................................ 84 SPI Protocol .................................................................................... 86 Wi-Fi ............................................................................................... 87 5 System Design ............................................................................................ 89 5.1 Power Systems .................................................................................... 89 Trimmers ........................................................................................ 89 Wheels ............................................................................................ 90 Accessories .................................................................................... 91 5.2 Navigation System ............................................................................... 91 Function Generator Design ............................................................. 92 EMF Sensor Design ....................................................................... 95 GPS Design and Schematics ......................................................... 99 IMU Design and Schematic .......................................................... 100 5.3 Physical Design ................................................................................. 103 iv Base Assembly ............................................................................. 103 Shell .............................................................................................. 104 Wheels .......................................................................................... 105 5.4 Microcontroller System ....................................................................... 107 5.5 Software Systems .............................................................................. 109 6 Demonstration and Testing ....................................................................... 112 6.1 Testing Plans ..................................................................................... 112 6.2 Testing Goals ..................................................................................... 113 Cutting Rate Test .......................................................................... 113 Cutting Height Adjustability Test ................................................... 114 Rover Stability Test ....................................................................... 114 Turning Radius Test ...................................................................... 114 Obstacle Avoidance Test .............................................................. 114 Autonomy Test .............................................................................. 114 Day/Night Run Test ....................................................................... 115 Weather Resistance Test .............................................................. 115 Battery