EncircleTrajectory Class Reference

Arc trajectory centred on the vehicle's starting position, with an outward spiral approach. More...

#include <EncircleTrajectory.h>

Inheritance diagram for EncircleTrajectory:

Public Member Functions
	EncircleTrajectory (const State &origin, double radius, double turn_angle, double tangent_offset, double spiral_proportion, std::shared_ptr< Trajectory6DOFLimits > vehicle_limits, const std::string &world_frame_id="world_ned")
	Constructs and plans the encircle trajectory. More...
bool	is_valid () const
	Returns true if trajectory planning succeeded. More...
bool	is_finished (double t) const override
	Returns true if the elapsed time has reached or exceeded the trajectory duration. More...
double	get_progress (double t) const override
	Returns trajectory progress as a fractional segment index. More...
double	get_expected_total_time () const override
	Returns the total planned trajectory duration. More...
Public Member Functions inherited from TrajectoryBase
virtual	~TrajectoryBase ()=default
void	start (double t)
	Records the start time of the trajectory. More...
State	get_model (double t, const State &curr_state)
	Returns the desired body-frame state at time t. More...
geometry_msgs::msg::PoseArray	get_visualization_msg (double t, double sample_hz=20.0) const
	Builds a PoseArray message sampling the trajectory for RViz visualisation. More...

Protected Member Functions
State	get_model_world (double t) const override
	Evaluates the polar trajectory and converts to a world-frame Cartesian State. More...
Protected Member Functions inherited from TrajectoryBase
double	get_elapsed_time (double t) const
	Returns elapsed time since start(), or 0 if not yet started. More...

Additional Inherited Members
Protected Attributes inherited from TrajectoryBase
std::shared_ptr< Trajectory6DOFLimits >	vehicle_limits_
	Velocity and acceleration limits for trajectory planning. More...
std::string	world_frame_id_
	TF frame ID embedded in visualisation message headers. More...
bool	started_ = false
	True after start() has been called. More...
double	start_time_ = 0.0
	ROS time at which start() was called. More...

Detailed Description

Arc trajectory centred on the vehicle's starting position, with an outward spiral approach.

The trajectory is planned in polar coordinates \((r, \theta)\) centred at the vehicle's starting position. \(r\) grows from \(0\) to \(r_{target}\) over the first \(\text{spiral\_proportion} \times |\Delta\theta|\) of the arc, then remains constant for the remainder. At every point the vehicle's yaw is aligned with the tangent to the instantaneous circle, plus an optional fixed offset.

Cartesian position, velocity, and acceleration are derived analytically from the polar trajectory at query time using the standard polar–Cartesian identities.

Constructor & Destructor Documentation

EncircleTrajectory()

EncircleTrajectory::EncircleTrajectory	(	const State &	origin,
		double	radius,
		double	turn_angle,
		double	tangent_offset,
		double	spiral_proportion,
		std::shared_ptr< Trajectory6DOFLimits >	vehicle_limits,
		const std::string &	world_frame_id = "world_ned"
	)

Constructs and plans the encircle trajectory.

Parameters

origin	[in] Starting vehicle state; the arc is centred at this position
radius	[in] Target orbit radius in metres
turn_angle	[in] Total arc angle in radians; positive = CCW, negative = CW
tangent_offset	[in] Yaw offset from the arc tangent in radians; 0 means the vehicle faces exactly along the direction of motion
spiral_proportion	[in] Fraction of the arc over which \(r\) grows from 0 to radius; 0 = move radially outward first then arc at full radius, 1 = spiral outward throughout the entire arc
vehicle_limits	[in] Per-axis velocity and acceleration limits
world_frame_id	[in] TF frame ID for visualisation messages

Member Function Documentation

get_expected_total_time()

double EncircleTrajectory::get_expected_total_time ( ) const

overridevirtual

Returns the total planned trajectory duration.

Returns

Duration in seconds

Implements TrajectoryBase.

get_model_world()

State EncircleTrajectory::get_model_world ( double  t ) const

overrideprotectedvirtual

Evaluates the polar trajectory and converts to a world-frame Cartesian State.

Parameters

t	[in] Current ROS time in seconds

Returns

Desired State in the world frame at the given time

Implements TrajectoryBase.

get_progress()

double EncircleTrajectory::get_progress ( double  t ) const

overridevirtual

Returns trajectory progress as a fractional segment index.

Parameters

t	[in] Current ROS time in seconds

Returns

Progress where integer values indicate segment boundaries

Implements TrajectoryBase.

is_finished()

bool EncircleTrajectory::is_finished ( double  t ) const

overridevirtual

Returns true if the elapsed time has reached or exceeded the trajectory duration.

Parameters

t	[in] Current ROS time in seconds

Returns

True when the trajectory is complete

Implements TrajectoryBase.

is_valid()

bool EncircleTrajectory::is_valid

(

)

const

Returns true if trajectory planning succeeded.

Returns

True if a valid trajectory was generated

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

• include/trajectory/EncircleTrajectory.h
• src/trajectory/EncircleTrajectory.cpp