challenge-bot.com Git - 3501/stronghold-2016/blob - src/org/usfirst/frc/team3501/robot/subsystems/DriveTrain.java

   1 package org.usfirst.frc.team3501.robot.subsystems;
   2
   3 import org.usfirst.frc.team3501.robot.Constants;
   4 import org.usfirst.frc.team3501.robot.Lidar;
   5
   6 import edu.wpi.first.wpilibj.CANTalon;
   7 import edu.wpi.first.wpilibj.CounterBase.EncodingType;
   8 import edu.wpi.first.wpilibj.Encoder;
   9 import edu.wpi.first.wpilibj.I2C;
  10 import edu.wpi.first.wpilibj.PIDController;
  11 import edu.wpi.first.wpilibj.command.Subsystem;
  12
  13 public class DriveTrain extends Subsystem {
  14   // Drivetrain related objects
  15   private Encoder leftEncoder, rightEncoder;
  16   public static Lidar lidar;
  17   private CANTalon frontLeft, frontRight, rearLeft, rearRight;
  18   private PIDController frontLeftC, frontRightC, rearLeftC, rearRightC;
  19   // Drivetrain specific constants that relate to the inches per pulse value for
  20   // the encoders
  21   private final static double WHEEL_DIAMETER = 6.0; // in inches
  22   private final static double PULSES_PER_ROTATION = 256; // in pulses
  23   private final static double OUTPUT_SPROCKET_DIAMETER = 2.0; // in inches
  24   private final static double WHEEL_SPROCKET_DIAMETER = 3.5; // in inches
  25   public final static double INCHES_PER_PULSE = (((Math.PI)
  26       * OUTPUT_SPROCKET_DIAMETER / PULSES_PER_ROTATION)
  27       / WHEEL_SPROCKET_DIAMETER) * WHEEL_DIAMETER;
  28
  29   // Drivetrain specific constants that relate to the PID controllers
  30   private final static double Kp = 1.0, Ki = 0.0,
  31       Kd = 0.0 * (OUTPUT_SPROCKET_DIAMETER / PULSES_PER_ROTATION)
  32           / (WHEEL_SPROCKET_DIAMETER) * WHEEL_DIAMETER;
  33
  34   public DriveTrain() {
  35     frontLeft = new CANTalon(Constants.DriveTrain.FRONT_LEFT);
  36     frontRight = new CANTalon(Constants.DriveTrain.FRONT_RIGHT);
  37     rearLeft = new CANTalon(Constants.DriveTrain.REAR_LEFT);
  38     rearRight = new CANTalon(Constants.DriveTrain.REAR_RIGHT);
  39
  40     lidar = new Lidar(I2C.Port.kOnboard);
  41     leftEncoder = new Encoder(Constants.DriveTrain.ENCODER_LEFT_A,
  42         Constants.DriveTrain.ENCODER_LEFT_B, false, EncodingType.k4X);
  43     rightEncoder = new Encoder(Constants.DriveTrain.ENCODER_RIGHT_A,
  44         Constants.DriveTrain.ENCODER_RIGHT_B, false, EncodingType.k4X);
  45     leftEncoder.setDistancePerPulse(Constants.DriveTrain.INCHES_PER_PULSE);
  46     rightEncoder.setDistancePerPulse(Constants.DriveTrain.INCHES_PER_PULSE);
  47     leftEncoder.setDistancePerPulse(INCHES_PER_PULSE);
  48     rightEncoder.setDistancePerPulse(INCHES_PER_PULSE);
  49
  50   }
  51
  52   @Override
  53   protected void initDefaultCommand() {
  54   }
  55
  56   public void resetEncoders() {
  57     leftEncoder.reset();
  58     rightEncoder.reset();
  59   }
  60
  61   public double getLidarDistance() {
  62     return lidar.pidGet();
  63   }
  64
  65   public double getRightSpeed() {
  66     return rightEncoder.getRate(); // in inches per second
  67   }
  68
  69   public double getLeftSpeed() {
  70     return leftEncoder.getRate(); // in inches per second
  71   }
  72
  73   public double getSpeed() {
  74     return (getLeftSpeed() + getRightSpeed()) / 2.0; // in inches per second
  75   }
  76
  77   public double getRightDistance() {
  78     return rightEncoder.getDistance(); // in inches
  79   }
  80
  81   public double getLeftDistance() {
  82     return leftEncoder.getDistance(); // in inches
  83   }
  84
  85   public double getDistance() {
  86     return (getRightDistance() + getLeftDistance()) / 2.0; // in inches
  87   }
  88
  89   public void stop() {
  90     setMotorSpeeds(0, 0);
  91   }
  92
  93   public void setMotorSpeeds(double leftSpeed, double rightSpeed) {
  94     // speed passed to right motor is negative because right motor rotates in
  95     // opposite direction
  96     this.frontLeft.set(leftSpeed);
  97     this.frontRight.set(-rightSpeed);
  98     this.rearLeft.set(leftSpeed);
  99     this.rearRight.set(-rightSpeed);
 100   }
 101 }