How to Control a Robot

1. How to Control a Robot Kickoff 2011

2. Why, How, Where? • Sense, think, act • Robot, laptop, your brain Game Robot Human Internal Sensors Game State External Sensors Robot’s Software Robot’s Actions Score Human Senses Drivers Brain User Interface

3. Moving in a Circle public void UserControlledCode() { while (true) { if (robot.isAutonomous == false) { lock (studentLock) { if (true) { //Ignore leftMotor.motorSpeed = 100; rightMotor.motorSpeed = -50; } Robot’s Software Robot’s Actions

4. Types and Variables • Declare : double x; • Assign : x = 3.5; • Use : int y = x; z = 8 - y + x; x = x + y; • = is assignment (not equals) • C#: Value type vs. Reference type • C# is case sensitive

5. Avoiding Obstacles Button = new InputPort((Cpu.Pin)FEZ_Pin.Digital.IO4, true, Port.ResistorMode.PullUp); if (Button.Read()) { leftMotor.motorSpeed = -60; rightMotor.motorSpeed = -30; Thread.Sleep(1000); }

6. More Avoiding Obstacles External Sensors Robot’s Software Robot’s Actions

7. Program Flow • Decision • Consequences Code Code Should I fire the balls? Should I fire the balls? True True False False Fire the Balls Reload the Shooter Fire the Balls More Code More Code

8. Program Flow if (isFiring) {shooter.shoot()} if (isFiring) {shooter.shoot()} else {shooter.reload()} if (condition1) {consequent1} else if (condition2) {cosequent2} else {alternative} • Use to change behavior depending on input

9. Tank Drive //-100<=motorSpeed<=100 //0<=Joystick values<=255 leftMotor.motorSpeed = ((double)(robot.UIAnalogVals[1] - 128) * 100 / (double)128); rightMotor.motorSpeed = ((double)(robot.UIAnalogVals[3] - 128) * 100 / (double)128);

10. More Tank Drive External Sensors Robot’s Software Robot’s Actions Human Senses Drivers Brain User Interface

11. Using Objects Cat john = new Cat(10); intjohnsMass = john.Eat(5); john.Purr(); john.name = "Johnny"; john.name = "John"; Console.WriteLine(john.name); Console.WriteLine(johnsMass);

12. More Objects • To create: new Type(arguments, ...); • Field or Property: variableName.member • Methods: variableName.member(argument,...)

13. Robotic Objects • Declare Objects here public class StudentCode { // Variables private Robot robot; private SimpleMotorControllerrightMotor; private InputPort Button; //More code

14. More Robotic Objects • Instantiate Objects here public StudentCode(Robot robot) { Button = new InputPort((Cpu.Pin)FEZ_Pin.Digital.IO4, true, Port.ResistorMode.PullUp); leftMotor = new SimpleMotorController(robot, "COM1", 13); rightMotor.motorBrake = 0;

15. Arrays myArray[] • To Create: int[] myArray = new int[5]; • To access elements: variableName[index]; • Size: myArray.Length • myArray[0] = 12; • Arrays are 0 indexed myArray[0] myArray[1] myArray[2] myArray[3] myArray[4]

16. Relational and Equality Operators • Turn numbers into booleans

17. Boolean Operators Exercise: (!(12-3 > 8) && (3*5 == 15)) || ( !(17 < 18) || true) if ( (time <= 30)  &&  !(mode == 2) ) { driveForward(); }

18. Tracing a Polygon inti = 0; while (i < 5) { leftMotor.motorSpeed = 50; rightMotor.motorSpeed = 50; Thread.Sleep(1000); leftMotor.motorSpeed = -50; Thread.Sleep(500); i++; }

19. Tracing a Polygon for (inti = 0; i < 5; i++) { leftMotor.motorSpeed = 50; rightMotor.motorSpeed = 50; Thread.Sleep(1000); leftMotor.motorSpeed = -50; Thread.Sleep(500); }

20. Loops initialize while (condition) { body postBody } for (initialize; condition; postbody) { body }

21. User Controlled Code public void UserControlledCode() { if (robot.isAutonomous == false) { lock (studentLock) { //All code for the teleoperated period goes here. It is in an infinite while loop so it is continuously executed. } } }