#include <tank_drive.h>

Public Types
enum class	BrakeType { None , ZeroVelocity , Smart }

Public Member Functions
	TankDrive (motor_group &left_motors, motor_group &right_motors, robot_specs_t &config, OdometryBase *odom=NULL)

void	stop ()

void	drive_tank (double left, double right, int power=1, BrakeType bt=BrakeType::None)

void	drive_tank_raw (double left, double right)

void	drive_arcade (double forward_back, double left_right, int power=1, BrakeType bt=BrakeType::None)

bool	drive_forward (double inches, directionType dir, Feedback &feedback, double max_speed=1, double end_speed=0)

bool	drive_forward (double inches, directionType dir, double max_speed=1, double end_speed=0)

bool	turn_degrees (double degrees, Feedback &feedback, double max_speed=1, double end_speed=0)

bool	turn_degrees (double degrees, double max_speed=1, double end_speed=0)

bool	drive_to_point (double x, double y, vex::directionType dir, Feedback &feedback, double max_speed=1, double end_speed=0)

bool	drive_to_point (double x, double y, vex::directionType dir, double max_speed=1, double end_speed=0)

bool	turn_to_heading (double heading_deg, Feedback &feedback, double max_speed=1, double end_speed=0)

bool	turn_to_heading (double heading_deg, double max_speed=1, double end_speed=0)

void	reset_auto ()

bool	pure_pursuit (PurePursuit::Path path, directionType dir, Feedback &feedback, double max_speed=1, double end_speed=0)

bool	pure_pursuit (PurePursuit::Path path, directionType dir, double max_speed=1, double end_speed=0)

Static Public Member Functions
static double	modify_inputs (double input, int power=2)

Detailed Description

TankDrive is a class to run a tank drive system. A tank drive system, sometimes called differential drive, has a motor (or group of synchronized motors) on the left and right side

Member Enumeration Documentation

◆ BrakeType

enum class TankDrive::BrakeType

strong

Enumerator
None	just send 0 volts to the motors
ZeroVelocity	try to bring the robot to rest. But don't try to hold position
Smart	bring the robot to rest and once it's stopped, try to hold that position

Constructor & Destructor Documentation

◆ TankDrive()

TankDrive::TankDrive	(	motor_group &	left_motors,
		motor_group &	right_motors,
		robot_specs_t &	config,
		OdometryBase *	odom = NULL )

Create the TankDrive object

Parameters

left_motors	left side drive motors
right_motors	right side drive motors
config	the configuration specification defining physical dimensions about the robot. See robot_specs_t for more info
odom	an odometry system to track position and rotation. this is necessary to execute autonomous paths

Member Function Documentation

◆ drive_arcade()

void TankDrive::drive_arcade	(	double	forward_back,
		double	left_right,
		int	power = 1,
		BrakeType	bt = BrakeType::None )

Drive the robot using arcade style controls. forward_back controls the linear motion, left_right controls the turning.

forward_back and left_right are in "percent": -1.0 -> 1.0

Parameters

forward_back	the percent to move forward or backward
left_right	the percent to turn left or right
power	modifies the input velocities left^power, right^power
bt	breaktype. What to do if the driver lets go of the sticks

Drive the robot using arcade style controls. forward_back controls the linear motion, left_right controls the turning.

left_motors and right_motors are in "percent": -1.0 -> 1.0

◆ drive_forward() [1/2]

bool TankDrive::drive_forward	(	double	inches,
		directionType	dir,
		double	max_speed = 1,
		double	end_speed = 0 )

Autonomously drive the robot forward a certain distance

Parameters

inches	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
dir	the direction we want to travel forward and backward
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Autonomously drive the robot forward a certain distance

Parameters

inches	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
dir	the direction we want to travel forward and backward
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have finished driving to our point

◆ drive_forward() [2/2]

bool TankDrive::drive_forward	(	double	inches,
		directionType	dir,
		Feedback &	feedback,
		double	max_speed = 1,
		double	end_speed = 0 )

Use odometry to drive forward a certain distance using a custom feedback controller

Returns whether or not the robot has reached it's destination.

Parameters

inches	the distance to drive forward
dir	the direction we want to travel forward and backward
feedback	the custom feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true when we have reached our target distance

Use odometry to drive forward a certain distance using a custom feedback controller

Returns whether or not the robot has reached it's destination.

Parameters

inches	the distance to drive forward
dir	the direction we want to travel forward and backward
feedback	the custom feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

◆ drive_tank()

void TankDrive::drive_tank	(	double	left,
		double	right,
		int	power = 1,
		BrakeType	bt = BrakeType::None )

Drive the robot using differential style controls. left_motors controls the left motors, right_motors controls the right motors.

left_motors and right_motors are in "percent": -1.0 -> 1.0

Parameters

left	the percent to run the left motors
right	the percent to run the right motors
power	modifies the input velocities left^power, right^power
bt	breaktype. What to do if the driver lets go of the sticks

◆ drive_tank_raw()

void TankDrive::drive_tank_raw	(	double	left,
		double	right )

Drive the robot raw-ly

Parameters

left	the percent to run the left motors (-1, 1)
right	the percent to run the right motors (-1, 1)

◆ drive_to_point() [1/2]

bool TankDrive::drive_to_point	(	double	x,
		double	y,
		vex::directionType	dir,
		double	max_speed = 1,
		double	end_speed = 0 )

Use odometry to automatically drive the robot to a point on the field. X and Y is the final point we want the robot. Here we use the default feedback controller from the drive_sys

Returns whether or not the robot has reached it's destination.

Parameters

x	the x position of the target
y	the y position of the target
dir	the direction we want to travel forward and backward
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Use odometry to automatically drive the robot to a point on the field. X and Y is the final point we want the robot. Here we use the default feedback controller from the drive_sys

Returns whether or not the robot has reached it's destination.

Parameters

x	the x position of the target
y	the y position of the target
dir	the direction we want to travel forward and backward
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have reached our target point

◆ drive_to_point() [2/2]

bool TankDrive::drive_to_point	(	double	x,
		double	y,
		vex::directionType	dir,
		Feedback &	feedback,
		double	max_speed = 1,
		double	end_speed = 0 )

Use odometry to automatically drive the robot to a point on the field. X and Y is the final point we want the robot.

Returns whether or not the robot has reached it's destination.

Parameters

x	the x position of the target
y	the y position of the target
dir	the direction we want to travel forward and backward
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Use odometry to automatically drive the robot to a point on the field. X and Y is the final point we want the robot.

Returns whether or not the robot has reached it's destination.

Parameters

x	the x position of the target
y	the y position of the target
dir	the direction we want to travel forward and backward
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have reached our target point

◆ modify_inputs()

double TankDrive::modify_inputs	(	double	input,
		int	power = 2 )

static

Create a curve for the inputs, so that drivers have more control at lower speeds. Curves are exponential, with the default being squaring the inputs.

Parameters

input	the input before modification
power	the power to raise input to

Returns: input ^ power (accounts for negative inputs and odd numbered powers)

Modify the inputs from the controller by squaring / cubing, etc Allows for better control of the robot at slower speeds

Parameters

input	the input signal -1 -> 1
power	the power to raise the signal to

Returns: input^power accounting for any sign issues that would arise with this naive solution

◆ pure_pursuit() [1/2]

bool TankDrive::pure_pursuit	(	PurePursuit::Path	path,
		directionType	dir,
		double	max_speed = 1,
		double	end_speed = 0 )

Drive the robot autonomously using a pure-pursuit algorithm - Input path with a set of waypoints - the robot will attempt to follow the points while cutting corners (radius) to save time (compared to stop / turn / start)

Use the default drive feedback

Parameters

path	The list of coordinates to follow, in order
dir	Run the bot forwards or backwards
max_speed	Limit the speed of the robot (for pid / pidff feedbacks)
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: True when the path is complete

Drive the robot autonomously using a pure-pursuit algorithm - Input path with a set of waypoints - the robot will attempt to follow the points while cutting corners (radius) to save time (compared to stop / turn / start)

Use the default drive feedback

Parameters

path	The list of coordinates to follow, in order
dir	Run the bot forwards or backwards
max_speed	Limit the speed of the robot (for pid / pidff feedbacks)

Returns: True when the path is complete

◆ pure_pursuit() [2/2]

bool TankDrive::pure_pursuit	(	PurePursuit::Path	path,
		directionType	dir,
		Feedback &	feedback,
		double	max_speed = 1,
		double	end_speed = 0 )

Drive the robot autonomously using a pure-pursuit algorithm - Input path with a set of waypoints - the robot will attempt to follow the points while cutting corners (radius) to save time (compared to stop / turn / start)

Parameters

path	The list of coordinates to follow, in order
dir	Run the bot forwards or backwards
feedback	The feedback controller determining speed
max_speed	Limit the speed of the robot (for pid / pidff feedbacks)
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: True when the path is complete

Drive the robot autonomously using a pure-pursuit algorithm - Input path with a set of waypoints - the robot will attempt to follow the points while cutting corners (radius) to save time (compared to stop / turn / start)

Parameters

path	The list of coordinates to follow, in order
dir	Run the bot forwards or backwards
feedback	The feedback controller determining speed
max_speed	Limit the speed of the robot (for pid / pidff feedbacks)

Returns: True when the path is complete

◆ reset_auto()

void TankDrive::reset_auto ( )

Reset the initialization for autonomous drive functions

◆ stop()

void TankDrive::stop ( )

Stops rotation of all the motors using their "brake mode"

◆ turn_degrees() [1/2]

bool TankDrive::turn_degrees	(	double	degrees,
		double	max_speed = 1,
		double	end_speed = 0 )

Autonomously turn the robot X degrees to counterclockwise (negative for clockwise), with a maximum motor speed of percent_speed (-1.0 -> 1.0)

Uses the defualt turning feedback of the drive system.

Parameters

degrees	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Autonomously turn the robot X degrees to counterclockwise (negative for clockwise), with a maximum motor speed of percent_speed (-1.0 -> 1.0)

Uses the defualt turning feedback of the drive system.

Parameters

degrees	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we turned te target number of degrees

◆ turn_degrees() [2/2]

bool TankDrive::turn_degrees	(	double	degrees,
		Feedback &	feedback,
		double	max_speed = 1,
		double	end_speed = 0 )

Autonomously turn the robot X degrees counterclockwise (negative for clockwise), with a maximum motor speed of percent_speed (-1.0 -> 1.0)

Uses PID + Feedforward for it's control.

Parameters

degrees	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power

Autonomously turn the robot X degrees to counterclockwise (negative for clockwise), with a maximum motor speed of percent_speed (-1.0 -> 1.0)

Uses the specified feedback for it's control.

Parameters

degrees	degrees by which we will turn relative to the robot (+) turns ccw, (-) turns cw
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have turned our target number of degrees

◆ turn_to_heading() [1/2]

bool TankDrive::turn_to_heading	(	double	heading_deg,
		double	max_speed = 1,
		double	end_speed = 0 )

Turn the robot in place to an exact heading relative to the field. 0 is forward. Uses the defualt turn feedback of the drive system

Parameters

heading_deg	the heading to which we will turn
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Turn the robot in place to an exact heading relative to the field. 0 is forward. Uses the defualt turn feedback of the drive system

Parameters

heading_deg	the heading to which we will turn
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have reached our target heading

◆ turn_to_heading() [2/2]

bool TankDrive::turn_to_heading	(	double	heading_deg,
		Feedback &	feedback,
		double	max_speed = 1,
		double	end_speed = 0 )

Turn the robot in place to an exact heading relative to the field. 0 is forward.

Parameters

heading_deg	the heading to which we will turn
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Turn the robot in place to an exact heading relative to the field. 0 is forward.

Parameters

heading_deg	the heading to which we will turn
feedback	the feedback controller we will use to travel. controls the rate at which we accelerate and drive.
max_speed	the maximum percentage of robot speed at which the robot will travel. 1 = full power
end_speed	the movement profile will attempt to reach this velocity by its completion

Returns: true if we have reached our target heading

The documentation for this class was generated from the following files:

tank_drive.h
tank_drive.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ BrakeType

Constructor & Destructor Documentation

◆ TankDrive()

Member Function Documentation

◆ drive_arcade()

◆ drive_forward() [1/2]

◆ drive_forward() [2/2]

◆ drive_tank()

◆ drive_tank_raw()

◆ drive_to_point() [1/2]

◆ drive_to_point() [2/2]

◆ modify_inputs()

◆ pure_pursuit() [1/2]

◆ pure_pursuit() [2/2]

◆ reset_auto()

◆ stop()

◆ turn_degrees() [1/2]

◆ turn_degrees() [2/2]

◆ turn_to_heading() [1/2]

◆ turn_to_heading() [2/2]