lejos.robotics.navigation
Class SegowayPilot

java.lang.Object
  java.lang.Thread
      lejos.robotics.navigation.Segoway
          lejos.robotics.navigation.SegowayPilot

All Implemented Interfaces:

Runnable, ArcMoveController, ArcRotateMoveController, MoveController, MoveProvider, RotateMoveController

public class SegowayPilot
extends Segoway
implements ArcRotateMoveController

Allow standard moves with a Segoway robot. Currently the robot has a 5 second delay between moves to allow it some time to rebalance and straighten out uneven tacho rotations. This can be changed with setMoveDelay().

This code will work with any Segway-style robot, but tall robots will have problems balancing when the robot is moving. To counteract this, use larger wheels and/or slow down the speed using setTravelSpeed(). Make sure the battery is fully charged. The robot is more stable on carpet than hardwood at higher speeds.

The default speed is 50, which can be changed with setTravelSpeed().

Author:

BB

See Also:

Segoway

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.UncaughtExceptionHandler

Field Summary

static int	ARC_B
static int	ARC_F
static int	BACKWARD_T
static int	FORWARD_T
static int	ROTATE_L
static int	ROTATE_R
int	SPEED
static int	STOP

Fields inherited from class lejos.robotics.navigation.Segoway

left_motor, right_motor

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Fields inherited from interface lejos.robotics.navigation.MoveController

WHEEL_SIZE_NXT1, WHEEL_SIZE_NXT2, WHEEL_SIZE_RCX

Fields inherited from interface lejos.robotics.navigation.MoveController

WHEEL_SIZE_NXT1, WHEEL_SIZE_NXT2, WHEEL_SIZE_RCX

Constructor Summary

SegowayPilot(EncoderMotor left, EncoderMotor right, Gyroscope gyro, double wheelDiameter, double trackWidth)
Creates an instance of SegowayPilot.

Method Summary

void	addMoveListener(MoveListener m) Adds a MoveListener that will be notified of all movement events.
void	arc(double radius, double angle) Moves the NXT robot along an arc with a specified radius and angle, after which the robot stops moving.
void	arc(double radius, double angle, boolean immediateReturn) Moves the NXT robot along an arc with a specified radius and angle, after which the robot stops moving.
void	arcBackward(double radius) Starts the NXT robot moving backward along an arc with a specified radius.
void	arcForward(double radius) Starts the NXT robot moving forward along an arc with a specified radius.
void	backward() Starts the NXT robot moving backwards.
void	forward() Starts the NXT robot moving forward.
float	getAngleIncrement()
double	getMaxTravelSpeed() Returns the maximum speed at which this robot is capable of traveling forward and backward.
double	getMinRadius() The minimum steering radius this vehicle is capable of when traveling in an arc.
Move	getMovement() Returns the move made since the move started, but before it has completed.
double	getMovementIncrement()
double	getRotateMaxSpeed() returns the maximum value of the rotation speed;
double	getRotateSpeed() Returns the value of the rotation speed
double	getTravelSpeed() Returns the speed at which the robot will travel forward and backward (and to some extent arcs, although actual arc speed is slightly less).
boolean	isMoving() true if the robot is moving
void	rotate(double angle) Rotates the NXT robot the specified number of degrees; direction determined by the sign of the parameter.
void	rotate(double degrees, boolean immediateReturn) Rotates the NXT robot the specified number of degrees; direction determined by the sign of the parameter.
void	setMinRadius(double radius) Set the radius of the minimum turning circle.
void	setMoveDelay(int millis) Set the delay between movements which allows the Segoway to recover balance.
void	setRotateSpeed(double arg0) sets the rotation speed of the robot (the angular velocity of the rotate() methods)
void	setTravelSpeed(double speed) Currently this method isn't properly implemented with the proper units.
void	steer(double turnRate, double angle, boolean immediateReturn) Moves the robot along a curved path for a specified angle of rotation.
void	stop() Halts the NXT robot
void	travel(double distance) Moves the NXT robot a specific distance.
void	travel(double distance, boolean immediateReturn) Moves the NXT robot a specific distance.
void	travelArc(double radius, double distance) Moves the NXT robot a specified distance along an arc of specified radius, after which the robot stops moving.
void	travelArc(double radius, double distance, boolean immediateReturn) Moves the NXT robot a specified distance along an arc of specified radius, after which the robot stops moving.

Methods inherited from class lejos.robotics.navigation.Segoway

run, wheelDriver

Methods inherited from class java.lang.Thread

currentThread, getDefaultUncaughtExceptionHandler, getName, getPriority, getUncaughtExceptionHandler, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, start, yield

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SPEED

public int SPEED

STOP

public static final int STOP

See Also:

Constant Field Values

FORWARD_T

public static final int FORWARD_T

See Also:

Constant Field Values

BACKWARD_T

public static final int BACKWARD_T

See Also:

Constant Field Values

ROTATE_L

public static final int ROTATE_L

See Also:

Constant Field Values

ROTATE_R

public static final int ROTATE_R

See Also:

Constant Field Values

ARC_F

public static final int ARC_F

See Also:

Constant Field Values

ARC_B

public static final int ARC_B

See Also:

Constant Field Values

Constructor Detail

SegowayPilot

public SegowayPilot(EncoderMotor left,
                    EncoderMotor right,
                    Gyroscope gyro,
                    double wheelDiameter,
                    double trackWidth)

Creates an instance of SegowayPilot.

Parameters:

left - The left motor.

right - The right motor.

gyro - A generic gyroscope

wheelDiameter - The diameter of the wheel. For convenience, use the WHEEL_SIZE_XXX constants.

trackWidth - Distance between the center of the right tire and left tire. Use the same units as wheelDiameter.

Method Detail

steer

public void steer(double turnRate,
                  double angle,
                  boolean immediateReturn)

Moves the robot along a curved path for a specified angle of rotation. This method is similar to the arc(double radius, double angle, boolean immediateReturn) method except it uses the turnRate() parameter to determine the curvature of the path and therefore has the ability to drive straight. This makes it useful for line following applications. This method has the ability to return immediately by using the immediateReturn parameter set to true.

The turnRate specifies the sharpness of the turn. Use values between -200 and +200.
For details about how this parameter works, see DifferentialPilot.steer(double, double)

The robot will stop when its heading has changed by the amount of the angle parameter.
If angle is positive, the robot will move in the direction that increases its heading (it turns left).
If angle is negative, the robot will move in the direction that decreases its heading (turns right).
If angle is zero, the robot will not move and the method returns immediately.
For more details about this parameter, see DifferentialPilot.steer(double, double)

Note: If you have specified a drift correction in the constructor it will not be applied in this method.

Parameters:

turnRate - If positive, the left side of the robot is on the inside of the turn. If negative, the left side is on the outside.

angle - The angle through which the robot will rotate. If negative, robot traces the turning circle backwards.

immediateReturn - If immediateReturn is true then the method returns immediately.

arc

public void arc(double radius,
                double angle,
                boolean immediateReturn)

Description copied from interface: ArcMoveController

Moves the NXT robot along an arc with a specified radius and angle, after which the robot stops moving. This method has the ability to return immediately by using the immediateReturn parameter.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, is zero, the robot rotates in place.

The robot will stop when the degrees it has moved along the arc equals angle.
If angle is positive, the robot will move travel forwards.
If angle is negative, the robot will move travel backwards. If angle is zero, the robot will not move and the method returns immediately.

Postcondition: Motor speeds are unpredictable.

Note: If you have specified a drift correction in the constructor it will not be applied in this method.

Specified by:

arc in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

angle - The sign of the angle determines the direction of robot motion. Positive drives the robot forward, negative drives it backward.

immediateReturn - If immediateReturn is true then the method returns immediately.

See Also:

ArcMoveController.travelArc(double, double, boolean)

forward

public void forward()

Description copied from interface: MoveController

Starts the NXT robot moving forward.

Specified by:

forward in interface MoveController

backward

public void backward()

Description copied from interface: MoveController

Starts the NXT robot moving backwards.

Specified by:

backward in interface MoveController

setMoveDelay

public void setMoveDelay(int millis)

Set the delay between movements which allows the Segoway to recover balance. Default value is five seconds (5000 millis).

stop

public void stop()

Description copied from interface: MoveController

Halts the NXT robot

Specified by:

stop in interface MoveController

travel

public void travel(double distance,
                   boolean immediateReturn)

Description copied from interface: MoveController

Moves the NXT robot a specific distance. A positive value moves it forward and a negative value moves it backward.

Specified by:

travel in interface MoveController

Parameters:

distance - The positive or negative distance to move the robot, in wheel diameter units.

immediateReturn - If immediateReturn is true then the method returns immediately.

rotate

public void rotate(double degrees,
                   boolean immediateReturn)

Description copied from interface: RotateMoveController

Rotates the NXT robot the specified number of degrees; direction determined by the sign of the parameter. Motion stops when rotation is done.

Specified by:

rotate in interface RotateMoveController

Parameters:

degrees - The angle to rotate in degrees. A positive value rotates left, a negative value right (clockwise).

immediateReturn - If immediateReturn is true then the method returns immediately

getMaxTravelSpeed

public double getMaxTravelSpeed()

Description copied from interface: MoveController

Returns the maximum speed at which this robot is capable of traveling forward and backward. Speed is measured in units/second. e.g. If wheel diameter is cm, then speed is cm/sec.

Specified by:

getMaxTravelSpeed in interface MoveController

Returns:

Speed in chosen units per second (e.g. cm/sec)

getMovementIncrement

public double getMovementIncrement()

getTravelSpeed

public double getTravelSpeed()

Description copied from interface: MoveController

Returns the speed at which the robot will travel forward and backward (and to some extent arcs, although actual arc speed is slightly less). Speed is measured in units/second. e.g. If wheel diameter is cm, then speed is cm/sec.

Specified by:

getTravelSpeed in interface MoveController

Returns:

Speed in chosen units per second (e.g. cm/sec)

setTravelSpeed

public void setTravelSpeed(double speed)

Currently this method isn't properly implemented with the proper units. Speed is just an arbitrary number up to about 200. At higher speed values it can be unstable. Currently it uses a default of 80 which is near the unstable speed. Will need to make this method use units/second.

Specified by:

setTravelSpeed in interface MoveController

Parameters:

speed - The speed to travel.

isMoving

public boolean isMoving()

Description copied from interface: MoveController

true if the robot is moving

Specified by:

isMoving in interface MoveController

Returns:

true if the robot is moving under power.

travel

public void travel(double distance)

Description copied from interface: MoveController

Moves the NXT robot a specific distance. A positive value moves it forward and a negative value moves it backward. Method returns when movement is done.

Specified by:

travel in interface MoveController

Parameters:

distance - The positive or negative distance to move the robot.

addMoveListener

public void addMoveListener(MoveListener m)

Description copied from interface: MoveProvider

Adds a MoveListener that will be notified of all movement events.

Specified by:

addMoveListener in interface MoveProvider

Parameters:

m - the move listener

getMovement

public Move getMovement()

Description copied from interface: MoveProvider

Returns the move made since the move started, but before it has completed. This method is used by GUI maps to display the movement of a robot in real time. The robot must be capable of determining the move while it is in motion.

Specified by:

getMovement in interface MoveProvider

Returns:

The move made since the move started.

getAngleIncrement

public float getAngleIncrement()

getRotateMaxSpeed

public double getRotateMaxSpeed()

Description copied from interface: RotateMoveController

returns the maximum value of the rotation speed;

Specified by:

getRotateMaxSpeed in interface RotateMoveController

Returns:

max rotation speed

getRotateSpeed

public double getRotateSpeed()

Description copied from interface: RotateMoveController

Returns the value of the rotation speed

Specified by:

getRotateSpeed in interface RotateMoveController

Returns:

the rotate speed in degrees per second

rotate

public void rotate(double angle)

Description copied from interface: RotateMoveController

Rotates the NXT robot the specified number of degrees; direction determined by the sign of the parameter. Method returns when rotation is done.

Specified by:

rotate in interface RotateMoveController

Parameters:

angle - The angle to rotate in degrees. A positive value rotates left, a negative value right (clockwise).

setRotateSpeed

public void setRotateSpeed(double arg0)

Description copied from interface: RotateMoveController

sets the rotation speed of the robot (the angular velocity of the rotate() methods)

Specified by:

setRotateSpeed in interface RotateMoveController

Parameters:

arg0 - in degrees per second

arc

public void arc(double radius,
                double angle)

Description copied from interface: ArcMoveController

Moves the NXT robot along an arc with a specified radius and angle, after which the robot stops moving. This method does not return until the robot has completed moving angle degrees along the arc.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, is zero, the robot rotates in place.

Robot will stop when the degrees it has moved along the arc equals angle.
If angle is positive, the robot will move travel forwards.
If angle is negative, the robot will move travel backwards. If angle is zero, the robot will not move and the method returns immediately.

Postcondition: Motor speeds are unpredictable.

Note: If you have specified a drift correction in the constructor it will not be applied in this method.

Specified by:

arc in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

angle - The sign of the angle determines the direction of robot motion. Positive drives the robot forward, negative drives it backward.

See Also:

ArcMoveController.travelArc(double, double)

arcBackward

public void arcBackward(double radius)

Description copied from interface: ArcMoveController

Starts the NXT robot moving backward along an arc with a specified radius.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, the robot rotates in place.

Postcondition: Motor speeds are unpredictable.

Note: If you have specified a drift correction in the constructor it will not be applied in this method.

Specified by:

arcBackward in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

arcForward

public void arcForward(double radius)

Description copied from interface: ArcMoveController

Starts the NXT robot moving forward along an arc with a specified radius.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, the robot rotates in place.

Postcondition: Motor speeds are unpredictable.

Note: If you have specified a drift correction in the constructor it will not be applied in this method.

Specified by:

arcForward in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

getMinRadius

public double getMinRadius()

Description copied from interface: ArcMoveController

The minimum steering radius this vehicle is capable of when traveling in an arc. Theoretically this should be identical for both forward and reverse travel. In practice?

Specified by:

getMinRadius in interface ArcMoveController

Returns:

the radius in degrees

setMinRadius

public void setMinRadius(double radius)

Description copied from interface: ArcMoveController

Set the radius of the minimum turning circle.

Specified by:

setMinRadius in interface ArcMoveController

Parameters:

radius - the radius in degrees

travelArc

public void travelArc(double radius,
                      double distance)

Description copied from interface: ArcMoveController

Moves the NXT robot a specified distance along an arc of specified radius, after which the robot stops moving. This method does not return until the robot has completed moving distance along the arc. The units (inches, cm) for distance must be the same as the units used for radius.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, the robot rotates in place

The robot will stop when it has moved along the arc distance units.
If distance is positive, the robot will move travel forwards.
If distance is negative, the robot will move travel backwards.
If distance is zero, the robot will not move and the method returns immediately.

Postcondition: Motor speeds are unpredictable.

Specified by:

travelArc in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

distance - to travel, in same units as radius. The sign of the distance determines the direction of robot motion. Positive drives the robot forward, negative drives it backward.

See Also:

ArcMoveController.arc(double, double)

travelArc

public void travelArc(double radius,
                      double distance,
                      boolean immediateReturn)

Description copied from interface: ArcMoveController

Moves the NXT robot a specified distance along an arc of specified radius, after which the robot stops moving. This method has the ability to return immediately by using the immediateReturn parameter. The units (inches, cm) for distance should be the same as the units used for radius.

If radius is positive, the robot arcs left, and the center of the turning circle is on the left side of the robot.
If radius is negative, the robot arcs right, and the center of the turning circle is on the right side of the robot.
If radius is zero, the robot rotates in place.

The robot will stop when it has moved along the arc distance units.
If distance is positive, the robot will move travel forwards.
If distance is negative, the robot will move travel backwards.
If distance is zero, the robot will not move and the method returns immediately.

Postcondition: Motor speeds are unpredictable.

Specified by:

travelArc in interface ArcMoveController

Parameters:

radius - of the arc path. If positive, the left side of the robot is on the inside of the turn. If negative, the left side of the robot is on the outside of the turn.

distance - to travel, in same units as radius. The sign of the distance determines the direction of robot motion. Positive drives the robot forward, negative drives it backward.

immediateReturn - If immediateReturn is true then the method returns immediately.

See Also:

ArcMoveController.arc(double, double, boolean)