class DriveTrain(Subsystem):
"""DriveTrain: is the subsystem responsible for motors and
devices associated with driving subystem.
As a subsystem, we represent the single point of contact
for all drivetrain-related controls. Specifically, commands
that manipulate the drivetrain should 'require' the singleton
instance (via require(robot.driveTrain)). Unless overridden,
our default command, JoystickDriver, is the means by which
driving occurs.
"""
k_minThrottleScale = 0.5
k_defaultDriveSpeed = 100.0 # ~13.0 ft/sec determined experimentally
k_maxDriveSpeed = 150.0 # ~20 ft/sec
k_maxTurnSpeed = 40.0 # ~3-4 ft/sec
k_fastTurn = -1
k_mediumTurn = -.72
k_slowTurn = -.55
k_quadTicksPerWheelRev = 9830
k_wheelDiameterInInches = 14.0
k_wheelCircumferenceInInches = k_wheelDiameterInInches * math.pi
k_quadTicksPerInch = k_quadTicksPerWheelRev / k_wheelCircumferenceInInches
k_turnKp = .1
k_turnKi = 0
k_turnKd = .3
k_turnKf = .001
k_ControlModeSpeed = 0
k_ControlModeVBus = 1
k_ControlModeDisabled = 2
class _turnHelper(PIDOutput):
"""a private helper class for PIDController-based
imu-guided turning.
"""
def __init__(self, driveTrain):
super().__init__()
self.driveTrain = driveTrain
def pidWrite(self, output):
self.driveTrain.turn(output * DriveTrain.k_maxTurnSpeed)
def __init__(self, robot, name=None):
super().__init__(name=name)
self.robot = robot
# STEP 1: instantiate the motor controllers
self.leftMasterMotor = CANTalon(robot.map.k_DtLeftMasterId)
self.leftFollowerMotor = CANTalon(robot.map.k_DtLeftFollowerId)
self.rightMasterMotor = CANTalon(robot.map.k_DtRightMasterId)
self.rightFollowerMotor = CANTalon(robot.map.k_DtRightFollowerId)
# Step 2: Configure the follower Talons: left & right back motors
self.leftFollowerMotor.changeControlMode(CANTalon.ControlMode.Follower)
self.leftFollowerMotor.set(self.leftMasterMotor.getDeviceID())
self.rightFollowerMotor.changeControlMode(CANTalon.ControlMode.Follower)
self.rightFollowerMotor.set(self.rightMasterMotor.getDeviceID())
# STEP 3: Setup speed control mode for the master Talons
self.leftMasterMotor.changeControlMode(CANTalon.ControlMode.Speed)
self.rightMasterMotor.changeControlMode(CANTalon.ControlMode.Speed)
# STEP 4: Indicate the feedback device used for closed-loop
# For speed mode, indicate the ticks per revolution
self.leftMasterMotor.setFeedbackDevice(CANTalon.FeedbackDevice.QuadEncoder)
self.rightMasterMotor.setFeedbackDevice(CANTalon.FeedbackDevice.QuadEncoder)
self.leftMasterMotor.configEncoderCodesPerRev(self.k_quadTicksPerWheelRev)
self.rightMasterMotor.configEncoderCodesPerRev(self.k_quadTicksPerWheelRev)
# STEP 5: Set PID values & closed loop error
self.leftMasterMotor.setPID(0.22, 0, 0)
self.rightMasterMotor.setPID(0.22, 0, 0)
# Add ramp up rate
self.leftMasterMotor.setVoltageRampRate(48.0) # max allowable voltage
# change /sec: reach to
# 12V after 1sec
self.rightMasterMotor.setVoltageRampRate(48.0)
# Add SmartDashboard controls for testing
# Add SmartDashboard live windowS
LiveWindow.addActuator("DriveTrain",
"Left Master %d" % robot.map.k_DtLeftMasterId,
self.leftMasterMotor)
LiveWindow.addActuator("DriveTrain",
"Right Master %d" % robot.map.k_DtRightMasterId,
self.rightMasterMotor)
# init RobotDrive - all driving should occur through its methods
# otherwise we expect motor saftey warnings
self.robotDrive = RobotDrive(self.leftMasterMotor, self.rightMasterMotor)
self.robotDrive.setSafetyEnabled(True)
# init IMU - used for driver & vision feedback as well as for
# some autonomous modes.
self.visionState = self.robot.visionState
self.imu = BNO055()
self.turnPID = PIDController(self.k_turnKp, self.k_turnKd, self.k_turnKf,
self.imu, DriveTrain._turnHelper(self))
self.turnPID.setOutputRange(-1, 1)
self.turnPID.setInputRange(-180, 180)
self.turnPID.setPercentTolerance(2)
self.turnMultiplier = DriveTrain.k_mediumTurn
self.maxSpeed = DriveTrain.k_defaultDriveSpeed
# self.setContinuous() ?
robot.info("Initialized DriveTrain")
def initForCommand(self, controlMode):
self.leftMasterMotor.setEncPosition(0) # async call
self.rightMasterMotor.setEncPosition(0)
self.robotDrive.stopMotor()
self.robotDrive.setMaxOutput(self.maxSpeed)
if controlMode == self.k_ControlModeSpeed:
self.leftMasterMotor.changeControlMode(CANTalon.ControlMode.Speed)
self.rightMasterMotor.changeControlMode(CANTalon.ControlMode.Speed)
elif controlMode == self.k_ControlModeVBus:
self.leftMasterMotor.changeControlMode(CANTalon.ControlMode.PercentVbus)
self.rightMasterMotor.changeControlMode(CANTalon.ControlMode.PercentVbus)
elif controlMode == self.k_ControlModeDisabled:
# unverified codepath
self.leftMasterMotor.disableControl()
self.rightMasterMotor.disableControl()
else:
self.robot.error("Unexpected control mode")
self.robot.info("driveTrain initDefaultCommand, controlmodes: %d %d" %
(self.leftMasterMotor.getControlMode(),
self.rightMasterMotor.getControlMode()))
def initDefaultCommand(self):
# control modes are integers values:
# 0 percentvbux
# 1 position
# 2 velocity
self.setDefaultCommand(JoystickDriver(self.robot))
self.robotDrive.stopMotor();
def updateDashboard(self):
# TODO: additional items?
SmartDashboard.putNumber("IMU heading", self.getCurrentHeading())
SmartDashboard.putNumber("IMU calibration", self.imu.getCalibration())
def stop(self):
self.robotDrive.stopMotor()
def joystickDrive(self, jsY, jsX, throttle):
""" joystickDrive - called by JoystickDriver command. Inputs
are always on the range [-1, 1]... These values can be scaled
for a better "feel", but should always be in a subset of this
range.
"""
if self.robot.isAutonomous or \
(math.fabs(jx) < 0.075 and math.fabs(jy) < .075):
# joystick dead zone or auto (where we've been scheduled via
# default command machinery)
self.robotDrive.stopMotor()
else:
st = self.scaleThrottle(throttle)
self.robotDrive.arcadeDrive(jsY*self.turnMultiplier, jsX*st)
def drive(self, outputmag, curve):
""" drive - used by drivestraight command..
"""
self.robotDrive.drive(outputmag, curve)
def driveStraight(self, speed):
"""driveStraight: invoked from AutoDriveStraight..
"""
# NB: maxOuput isn't applied via set so
# speed is supposedly measured in rpm but this depends on our
# initialization establishing encoding ticks per revolution.
# This is approximate so we rely on the observed values above.
# (DEFAULT_SPEED_MAX_OUTPUT)
if 0:
self.leftMasterMotor.set(speed)
self.rightMasterMotor.set(speed)
else:
# TODO: validate this codepath
moveValue = speed / self.maxSpeed
rotateValue = 0
self.robotDrive.arcadeDrive(moveValue, rotateValue)
def startAutoTurn(self, degrees):
self.robot.info("start autoturn from %d to %d" %
(self.getHeading(), degrees))
self.turnPID.reset()
self.turnPID.setSetpoint(degrees)
self.turnPID.enable()
def endAutoTurn(self):
if self.turnPID.isEnabled():
self.turnPID.disable()
def isAutoTurning(self):
return self.turnPID.isEnabled()
def isAutoTurnFinished(self):
return self.turnPID.onTarget()
def turn(self, speed):
"""turn takes a speed, not an angle...
A negative speed is interpretted as turn left.
Note that we bypass application of setMaxOutput Which
only applies to calls to robotDrive.
"""
# In order to turn left, we want the right wheels to go
# forward and left wheels to go backward (cf: tankDrive)
# Oddly, our right master motor is reversed, so we compensate here.
# speed < 0: turn left: rightmotor(negative) (forward),
# leftmotor(negative) (backward)
# speed > 0: turn right: rightmotor(positive) (backward)
# leftmotor(positive) (forward)
if 0:
self.leftMasterMotor.set(speed)
self.rightMasterMotor.set(speed)
else:
# TODO: validate this codepath
moveValue = 0
rotateValue = speed / self.maxSpeed
self.robotDrive.arcadeDrive(moveValue, rotateValue)
def trackVision(self):
"""presumed called by either autonomous or teleop commands to
allow the vision subsystem to guide the robot
"""
if self.visionState.DriveLockedOnTarget:
self.stop()
else:
if self.isAutoTurning():
if self.isAutoTurnFinished():
self.endAutoTurn()
self.visionState.DriveLockedOnTarget = True
else:
# setup for an auto-turn
h = self.getCurrentHeading()
tg = self.getTargetHeading(h)
self.startAutoTurn(tg)
def getCurrentHeading(self):
""" getCurrentHeading returns a value between -180 and 180
"""
return math.degrees(self.imu.getHeading()) # getHeading: -pi, pi
def scaleThrottle(self, rawThrottle):
""" scaleThrottle:
returns a scaled value between MIN_THROTTLE_SCALE and 1.0
MIN_THROTTLE_SCALE must be set to the lowest useful scale value through experimentation
Scale the joystick values by throttle before passing to the driveTrain
+1=bottom position; -1=top position
"""
# Throttle in the range of -1 to 1. We would like to change that to a
# range of MIN_THROTTLE_SCALE to 1. #First, multiply the raw throttle
# value by -1 to reverse it (makes "up" maximum (1), and "down" minimum (-1))
# Then, add 1 to make the range 0-2 rather than -1 to +1
# Then multiply by ((1-k_minThrottleScale)/2) to change the range to 0-(1-k_minThrottleScale)
# Finally add k_minThrottleScale to change the range to k_minThrottleScale to 1
#
# Check the results are in the range of k_minThrottleScale to 1, and clip
# it in case the math went horribly wrong.
result = ((rawThrottle * -1) + 1) * ((1-self.k_minThrottleScale) / 2) + self.k_minThrottleScale
if result < self.k_minThrottleScale:
# Somehow our math was wrong. Our value was too low, so force it to the minimum
result = self.k_mintThrottleScale
elif result > 1:
# Somehow our math was wrong. Our value was too high, so force it to the maximum
result = 1.0
return result
def modifyTurnSpeed(self, speedUp):
if speedUp:
self.turnMultiplier = self.k_mediumTurn
else:
self.turnMultiplier = self.k_slowTurn
def inchesToTicks(self, inches):
return int(self.k_quadTicksPerInch * inches)
def destinationReached(self, distance):
return math.fabs(self.leftMasterMotor.getEncPosition()) >= distance or \
math.fabs(self.rightMasterMotr.getEncPosition()) >= distance
class driveTrain(Component) :
def __init__(self, robot):
super().__init__()
self.robot = robot
# Constants
WHEEL_DIAMETER = 8
PI = 3.1415
ENCODER_TICK_COUNT_250 = 250
ENCODER_TICK_COUNT_360 = 360
ENCODER_GOAL = 0 # default
ENCODER_TOLERANCE = 1 # inch0
self.RPM = 4320/10.7
self.INCHES_PER_REV = WHEEL_DIAMETER * 3.1415
self.CONTROL_TYPE = False # False = disable PID components
self.LEFTFRONTCUMULATIVE = 0
self.LEFTBACKCUMULATIVE = 0
self.RIGHTFRONTCUMULATIVE = 0
self.RIGHTBACKCUMULATIVE = 0
self.rfmotor = CANTalon(0)
self.rbmotor = CANTalon(1)
self.lfmotor = CANTalon(2)
self.lbmotor = CANTalon(3)
self.lfmotor.reverseOutput(True)
self.lbmotor.reverseOutput(True)
#self.rfmotor.reverseOutput(True)
#self.rbmotor.reverseOutput(True)#practice bot only
self.rfmotor.enableBrakeMode(True)
self.rbmotor.enableBrakeMode(True)
self.lfmotor.enableBrakeMode(True)
self.lbmotor.enableBrakeMode(True)
absolutePosition = self.lbmotor.getPulseWidthPosition() & 0xFFF; # mask out the bottom12 bits, we don't care about the wrap arounds use the low level API to set the quad encoder signal
self.lbmotor.setEncPosition(absolutePosition)
absolutePosition = self.lfmotor.getPulseWidthPosition() & 0xFFF; # mask out the bottom12 bits, we don't care about the wrap arounds use the low level API to set the quad encoder signal
self.lfmotor.setEncPosition(absolutePosition)
absolutePosition = self.rbmotor.getPulseWidthPosition() & 0xFFF; # mask out the bottom12 bits, we don't care about the wrap arounds use the low level API to set the quad encoder signal
self.rbmotor.setEncPosition(absolutePosition)
absolutePosition = self.rfmotor.getPulseWidthPosition() & 0xFFF; # mask out the bottom12 bits, we don't care about the wrap arounds use the low level API to set the quad encoder signal
self.rfmotor.setEncPosition(absolutePosition)
self.rfmotor.setFeedbackDevice(CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
self.rbmotor.setFeedbackDevice(CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
self.lfmotor.setFeedbackDevice(CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
self.lbmotor.setFeedbackDevice(CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
#setting up the distances per rotation
self.lfmotor.configEncoderCodesPerRev(4096)
self.rfmotor.configEncoderCodesPerRev(4096)
self.lbmotor.configEncoderCodesPerRev(4096)
self.rbmotor.configEncoderCodesPerRev(4096)
self.lfmotor.setPID(0.0005, 0, 0.0, profile=0)
self.rfmotor.setPID(0.0005, 0, 0.0, profile=0)
self.lbmotor.setPID(0.0005, 0, 0.0, profile=0)
self.rbmotor.setPID(0.0005, 0, 0.0, profile=0)
self.lbmotor.configNominalOutputVoltage(+0.0, -0.0)
self.lbmotor.configPeakOutputVoltage(+12.0, -12.0)
self.lbmotor.setControlMode(CANTalon.ControlMode.Speed)
self.lfmotor.configNominalOutputVoltage(+0.0, -0.0)
self.lfmotor.configPeakOutputVoltage(+12.0, -12.0)
self.lfmotor.setControlMode(CANTalon.ControlMode.Speed)
self.rbmotor.configNominalOutputVoltage(+0.0, -0.0)
self.rbmotor.configPeakOutputVoltage(+12.0, -12.0)
self.rbmotor.setControlMode(CANTalon.ControlMode.Speed)
self.rfmotor.configNominalOutputVoltage(+0.0, -0.0)
self.rfmotor.configPeakOutputVoltage(+12.0, -12.0)
self.rfmotor.setControlMode(CANTalon.ControlMode.Speed)
self.rfmotor.setPosition(0)
self.rbmotor.setPosition(0)
self.lfmotor.setPosition(0)
self.lbmotor.setPosition(0)
self.lfmotor.reverseSensor(True)
self.lbmotor.reverseSensor(True)
'''
# changing the encoder output from DISTANCE to RATE (we're dumb)
self.lfencoder.setPIDSourceType(wpilib.PIDController.PIDSourceType.kRate)
self.lbencoder.setPIDSourceType(wpilib.PIDController.PIDSourceType.kRate)
self.rfencoder.setPIDSourceType(wpilib.PIDController.PIDSourceType.kRate)
self.rbencoder.setPIDSourceType(wpilib.PIDController.PIDSourceType.kRate)
# LiveWindow settings (Encoder)
wpilib.LiveWindow.addSensor("Drive Train", "Left Front Encoder", self.lfencoder)
wpilib.LiveWindow.addSensor("Drive Train", "Right Front Encoder", self.rfencoder)
wpilib.LiveWindow.addSensor("Drive Train", "Left Back Encoder", self.lbencoder)
wpilib.LiveWindow.addSensor("Drive Train", "Right Back Encoder", self.rbencoder)
'''
'''
# Checking the state of the encoders on the Smart Dashboard
wpilib.SmartDashboard.putBoolean("Right Front Encoder Enabled?", self.rfmotor.isSensorPresent)
wpilib.SmartDashboard.putBoolean("Right Back Encoder Enabled?", self.rbmotor.isSensorPresent)
wpilib.SmartDashboard.putBoolean("Left Front Encoder Enabled?", self.lfmotor.isSensorPresent)
wpilib.SmartDashboard.putBoolean("Left Back Encoder Enabled?", self.lbmotor.isSensorPresent)
'''
if self.CONTROL_TYPE:
# Initializing PID Controls
self.pidRightFront = wpilib.PIDController(0.002, 0.8, 0.005, 0, self.rfmotor.feedbackDevice, self.rfmotor, 0.02)
self.pidLeftFront = wpilib.PIDController(0.002, 0.8, 0.005, 0, self.lfmotor.feedbackDevice, self.lfmotor, 0.02)
self.pidRightBack = wpilib.PIDController(0.002, 0.8, 0.005, 0, self.rbmotor.feedbackDevice, self.rbmotor, 0.02)
self.pidLeftBack = wpilib.PIDController(0.002, 0.8, 0.005, 0, self.lbmotor.feedbackDevice, self.lbmotor, 0.02)
# PID Absolute Tolerance Settings
self.pidRightFront.setAbsoluteTolerance(0.05)
self.pidLeftFront.setAbsoluteTolerance(0.05)
self.pidRightBack.setAbsoluteTolerance(0.05)
self.pidLeftBack.setAbsoluteTolerance(0.05)
# PID Output Range Settings
self.pidRightFront.setOutputRange(-1, 1)
self.pidLeftFront.setOutputRange(-1, 1)
self.pidRightBack.setOutputRange(-1, 1)
self.pidLeftBack.setOutputRange(-1, 1)
# Enable PID
#self.enablePIDs()
'''
# LiveWindow settings (PID)
wpilib.LiveWindow.addActuator("Drive Train Right", "Right Front PID", self.pidRightFront)
wpilib.LiveWindow.addActuator("Drive Train Left", "Left Front PID", self.pidLeftFront)
wpilib.LiveWindow.addActuator("Drive Train Right", "Right Back PID", self.pidRightBack)
wpilib.LiveWindow.addActuator("Drive Train Left", "Left Back PID", self.pidLeftBack)
'''
self.dashTimer = Timer() # Timer for SmartDashboard updating
self.dashTimer.start()
'''
# Adding components to the LiveWindow (testing)
wpilib.LiveWindow.addActuator("Drive Train Left", "Left Front Motor", self.lfmotor)
wpilib.LiveWindow.addActuator("Drive Train Right", "Right Front Motor", self.rfmotor)
wpilib.LiveWindow.addActuator("Drive Train Left", "Left Back Motor", self.lbmotor)
wpilib.LiveWindow.addActuator("Drive Train Right", "Right Back Motor", self.rbmotor)
'''
def log(self):
#The log method puts interesting information to the SmartDashboard. (like velocity information)
'''
#no longer implemented because of change of hardware
wpilib.SmartDashboard.putNumber("Left Front Speed", self.lfmotor.getEncVelocity())
wpilib.SmartDashboard.putNumber("Right Front Speed", self.rfmotor.getEncVelocity())
wpilib.SmartDashboard.putNumber("Left Back Speed", self.lbmotor.getEncVelocity())
wpilib.SmartDashboard.putNumber("Right Back Speed", self.rbmotor.getEncVelocity())
'''
wpilib.SmartDashboard.putNumber("RF Mag Enc Position", self.rfmotor.getPosition())
wpilib.SmartDashboard.putNumber("RB Mag Enc Position", self.rbmotor.getPosition())
wpilib.SmartDashboard.putNumber("LF Mag Enc Position", self.lfmotor.getPosition())
wpilib.SmartDashboard.putNumber("LB Mag Enc Position", self.lbmotor.getPosition())
'''
wpilib.SmartDashboard.putNumber("Right Front Mag Distance(inches)", self.convertEncoderRaw(self.rfmotor.getPosition()*0.57))
wpilib.SmartDashboard.putNumber("Right Back Mag Distance(inches)", self.convertEncoderRaw(self.rbmotor.getPosition()*0.57))
wpilib.SmartDashboard.putNumber("Left Front Mag Distance(inches)", self.convertEncoderRaw(self.lfmotor.getPosition()*0.57))
wpilib.SmartDashboard.putNumber("Left Back Mag Distance(inches)", self.convertEncoderRaw(self.lbmotor.getPosition()*0.57))
'''
# drive forward function
def drive_forward(self, speed) :
self.drive.tankDrive(speed, speed, True)
# manual drive function for Tank Drive
def xboxTankDrive(self, leftSpeed, rightSpeed, leftB, rightB, leftT, rightT):
#self.lfmotor.setCloseLoopRampRate(1)
#self.lbmotor.setCloseLoopRampRate(1)
#self.rfmotor.setCloseLoopRampRate(1)
#self.rbmotor.setCloseLoopRampRate(1)
if (leftB == True): #Straight Button
rightSpeed = leftSpeed
if (rightB == True): #Slow Button
#leftSpeed = leftSpeed/1.75
#rightSpeed = rightSpeed/1.75
if(not(leftSpeed < -0.5 and rightSpeed > 0.5 or leftSpeed > -0.5 and rightSpeed < 0.5)): #only do t if not turning
leftSpeed = leftSpeed/1.75
rightSpeed = rightSpeed/1.75
# Fast button
if(rightT == True):
#self.lfmotor.setCloseLoopRampRate(24)
#self.lbmotor.setCloseLoopRampRate(24)
#self.rfmotor.setCloseLoopRampRate(24)
#self.rbmotor.setCloseLoopRampRate(24)
leftSpeed = leftSpeed*(1.75)
rightSpeed = rightSpeed*(1.75)
if(leftT == True):
leftSpeed = 0.1
rightSpeed = 0.1
# Creating margin for error when using the joysticks, as they're quite sensitive
if abs(rightSpeed) < 0.04 :
rightSpeed = 0
if abs(leftSpeed) < 0.04 :
leftSpeed = 0
if self.CONTROL_TYPE:
self.pidRightFront.setSetpoint(rightSpeed)
self.pidRightBack.setSetpoint(rightSpeed)
self.pidLeftFront.setSetpoint(leftSpeed)
self.pidLeftBack.setSetpoint(leftSpeed)
else:
self.lfmotor.set(leftSpeed*512)
self.rfmotor.set(rightSpeed*512)
self.lbmotor.set(leftSpeed*512)
self.rbmotor.set(rightSpeed*512)
#autononmous tank drive (to remove a need for a slow, striaght, or fast button)
def autonTankDrive(self, leftSpeed, rightSpeed):
self.log()
#self.drive.tankDrive(leftSpeed, rightSpeed, True)
self.rfmotor.set(rightSpeed)
self.rbmotor.set(rightSpeed*(-1))
self.lfmotor.set(leftSpeed)
self.lbmotor.set(leftSpeed*(-1))
# stop function
def drive_stop(self) :
self.drive.tankDrive(0,0)
# fucntion to reset the PID's and encoder values
def reset(self):
self.rfmotor.setPosition(0)
self.rbmotor.setPosition(0)
self.lfmotor.setPosition(0)
self.lbmotor.setPosition(0)
if self.CONTROL_TYPE:
self.LEFTFRONTCUMULATIVE = 0
self.RIGHTFRONTCUMULATIVE = 0
self.LEFTBACKCUMULATIVE= 0
self.RIGHTBACKCUMULATIVE = 0
self.pidLeftBack.setSetpoint(0)
self.pidLeftFront.setSetpoint(0)
self.pidRightBack.setSetpoint(0)
self.pidRightFront.setSetpoint(0)
# def getDistance(self)
# return (abs(self.convertEncoderRaw(LEFTFRONTCUMULATIVE) + abs(self.convertEncoderRaw(LEFTBACKCUMULATIVE)) + abs(self.convertEncoderRaw(RIGHTFRONTCUMULATIVE)) + abs(self.convertEncoderRaw(RIGHTBACKCUMULATIVE)))
def turn_angle(self, degrees):
desired_inches = self.INCHES_PER_DEGREE * degrees
if degrees < 0:
while (abs(self.lfencoder.getDistance()) + abs(self.rfencoder.getDistance())) <= desired_inches :
self.autonTankDrive(0.4, -0.4)
elif degrees > 0:
while (abs(self.lfencoder.getDistance()) + abs(self.rfencoder.getDistance())) <= desired_inches :
self.autonTankDrive(-0.4, 0.4)
# Enable PID Controllers
def enablePIDs(self):
'''
#No longer required because we swapped from analog encoders to magnetic encoders
self.pidLeftFront.enable()
self.pidLeftBack.enable()
self.pidRightFront.enable()
self.pidRightBack.enable()
'''
# Disable PID Controllers
def disablePIDs(self):
'''
#see explaination above
self.pidLeftFront.disable()
self.pidLeftBack.disable()
self.pidRightFront.disable()
self.pidRightBack.disable()
'''
def getAutonDistance(self):
return (self.convertEncoderRaw(abs(self.rfmotor.getPosition()*0.57))
+ self.convertEncoderRaw(abs(self.rbmotor.getPosition()*0.57))
+ self.convertEncoderRaw(abs(self.lfmotor.getPosition()*0.57))
+ self.convertEncoderRaw(abs(self.lbmotor.getPosition()*0.57)))/4
#detirmines how many ticks the encoder has processed
def getMotorDistance(self, motor, cumulativeDistance):
currentRollovers = 0 #number of times the encoder has gone from 1023 to 0
previousValue = cumulativeDistance #variable for comparison
currentValue = motor.getEncPosition() #variable for comparison
if(previousValue > currentValue): #checks to see if the encoder reset itself from 1023 to 0
currentRollovers += 1 #notes the rollover
return currentValue + (currentRollovers * 1024) #adds current value to the number of rollovers, each rollover == 1024 ticks
#converts ticks from getMotorDistance into inches
def convertEncoderRaw(self, selectedEncoderValue):
return selectedEncoderValue * self.INCHES_PER_REV
