mavsdk::Winch Class Reference

#include: winch.h

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Allows users to send winch actions, as well as receive status information from winch systems.

Data Structures

struct Status

struct StatusFlags

Public Types

Type	Description
enum WinchAction	Winch Action type.
enum Result	Possible results returned for winch action requests.
std::function< void(Result)> ResultCallback	Callback type for asynchronous Winch calls.
std::function< void(Status)> StatusCallback	Callback type for subscribe_status.
Handle< Status > StatusHandle	Handle type for subscribe_status.

Public Member Functions

Type	Name	Description
	Winch (System & system)	Constructor. Creates the plugin for a specific System.
	Winch (std::shared_ptr< System > system)	Constructor. Creates the plugin for a specific System.
	~Winch () override	Destructor (internal use only).
	Winch (const Winch & other)	Copy constructor.
StatusHandle	subscribe_status (const StatusCallback & callback)	Subscribe to 'winch status' updates.
void	unsubscribe_status (StatusHandle handle)	Unsubscribe from subscribe_status.
Status	status () const	Poll for 'Status' (blocking).
void	relax_async (uint32_t instance, const ResultCallback callback)	Allow motor to freewheel.
Result	relax (uint32_t instance)const	Allow motor to freewheel.
void	relative_length_control_async (uint32_t instance, float length_m, float rate_m_s, const ResultCallback callback)	Wind or unwind specified length of line, optionally using specified rate.
Result	relative_length_control (uint32_t instance, float length_m, float rate_m_s)const	Wind or unwind specified length of line, optionally using specified rate.
void	rate_control_async (uint32_t instance, float rate_m_s, const ResultCallback callback)	Wind or unwind line at specified rate.
Result	rate_control (uint32_t instance, float rate_m_s)const	Wind or unwind line at specified rate.
void	lock_async (uint32_t instance, const ResultCallback callback)	Perform the locking sequence to relieve motor while in the fully retracted position.
Result	lock (uint32_t instance)const	Perform the locking sequence to relieve motor while in the fully retracted position.
void	deliver_async (uint32_t instance, const ResultCallback callback)	Sequence of drop, slow down, touch down, reel up, lock.
Result	deliver (uint32_t instance)const	Sequence of drop, slow down, touch down, reel up, lock.
void	hold_async (uint32_t instance, const ResultCallback callback)	Engage motor and hold current position.
Result	hold (uint32_t instance)const	Engage motor and hold current position.
void	retract_async (uint32_t instance, const ResultCallback callback)	Return the reel to the fully retracted position.
Result	retract (uint32_t instance)const	Return the reel to the fully retracted position.
void	load_line_async (uint32_t instance, const ResultCallback callback)	Load the reel with line.
Result	load_line (uint32_t instance)const	Load the reel with line.
void	abandon_line_async (uint32_t instance, const ResultCallback callback)	Spool out the entire length of the line.
Result	abandon_line (uint32_t instance)const	Spool out the entire length of the line.
void	load_payload_async (uint32_t instance, const ResultCallback callback)	Spools out just enough to present the hook to the user to load the payload.
Result	load_payload (uint32_t instance)const	Spools out just enough to present the hook to the user to load the payload.
const Winch &	operator= (const Winch &)=delete	Equality operator (object is not copyable).

Constructor & Destructor Documentation

Winch()

mavsdk::Winch::Winch(System &system)

Constructor. Creates the plugin for a specific System.

The plugin is typically created as shown below:

auto winch = Winch(system);

Parameters

• System& system - The specific system associated with this plugin.

Winch()

mavsdk::Winch::Winch(std::shared_ptr< System > system)

Constructor. Creates the plugin for a specific System.

The plugin is typically created as shown below:

auto winch = Winch(system);

Parameters

• std::shared_ptr< System > system - The specific system associated with this plugin.

~Winch()

mavsdk::Winch::~Winch() override

Destructor (internal use only).

Winch()

mavsdk::Winch::Winch(const Winch &other)

Copy constructor.

Parameters

• const Winch& other -

Member Typdef Documentation

typedef ResultCallback

using mavsdk::Winch::ResultCallback =  std::function<void(Result)>

Callback type for asynchronous Winch calls.

typedef StatusCallback

using mavsdk::Winch::StatusCallback =  std::function<void(Status)>

Callback type for subscribe_status.

typedef StatusHandle

using mavsdk::Winch::StatusHandle =  Handle<Status>

Handle type for subscribe_status.

Member Enumeration Documentation

enum WinchAction

Winch Action type.

Value	Description
Relaxed	Allow motor to freewheel.
RelativeLengthControl	Wind or unwind specified length of line, optionally using specified rate.
RateControl	Wind or unwind line at specified rate.
Lock	Perform the locking sequence to relieve motor while in the fully retracted position.
Deliver	Sequence of drop, slow down, touch down, reel up, lock.
Hold	Engage motor and hold current position.
Retract	Return the reel to the fully retracted position.
LoadLine	Load the reel with line. The winch will calculate the total loaded length and stop when the tension exceeds a threshold.
AbandonLine	Spool out the entire length of the line.
LoadPayload	Spools out just enough to present the hook to the user to load the payload.

enum Result

Possible results returned for winch action requests.

Value	Description
Unknown	Unknown result.
Success	Request was successful.
NoSystem	No system is connected.
Busy	Temporarily rejected.
Timeout	Request timed out.
Unsupported	Action not supported.
Failed	Action failed.

Member Function Documentation

subscribe_status()

StatusHandle mavsdk::Winch::subscribe_status(const StatusCallback &callback)

Subscribe to 'winch status' updates.

Parameters

• const StatusCallback& callback -

Returns

 StatusHandle -

unsubscribe_status()

void mavsdk::Winch::unsubscribe_status(StatusHandle handle)

Unsubscribe from subscribe_status.

Parameters

• StatusHandle handle -

status()

Status mavsdk::Winch::status() const

Poll for 'Status' (blocking).

Returns

 Status - One Status update.

relax_async()

void mavsdk::Winch::relax_async(uint32_t instance, const ResultCallback callback)

Allow motor to freewheel.

This function is non-blocking. See 'relax' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

relax()

Result mavsdk::Winch::relax(uint32_t instance) const

Allow motor to freewheel.

This function is blocking. See 'relax_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

relative_length_control_async()

void mavsdk::Winch::relative_length_control_async(uint32_t instance, float length_m, float rate_m_s, const ResultCallback callback)

Wind or unwind specified length of line, optionally using specified rate.

This function is non-blocking. See 'relative_length_control' for the blocking counterpart.

Parameters

• uint32_t instance -
• float length_m -
• float rate_m_s -
• const ResultCallback callback -

relative_length_control()

Result mavsdk::Winch::relative_length_control(uint32_t instance, float length_m, float rate_m_s) const

Wind or unwind specified length of line, optionally using specified rate.

This function is blocking. See 'relative_length_control_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -
• float length_m -
• float rate_m_s -

Returns

 Result - Result of request.

rate_control_async()

void mavsdk::Winch::rate_control_async(uint32_t instance, float rate_m_s, const ResultCallback callback)

Wind or unwind line at specified rate.

This function is non-blocking. See 'rate_control' for the blocking counterpart.

Parameters

• uint32_t instance -
• float rate_m_s -
• const ResultCallback callback -

rate_control()

Result mavsdk::Winch::rate_control(uint32_t instance, float rate_m_s) const

Wind or unwind line at specified rate.

This function is blocking. See 'rate_control_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -
• float rate_m_s -

Returns

 Result - Result of request.

lock_async()

void mavsdk::Winch::lock_async(uint32_t instance, const ResultCallback callback)

Perform the locking sequence to relieve motor while in the fully retracted position.

This function is non-blocking. See 'lock' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

lock()

Result mavsdk::Winch::lock(uint32_t instance) const

Perform the locking sequence to relieve motor while in the fully retracted position.

This function is blocking. See 'lock_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

deliver_async()

void mavsdk::Winch::deliver_async(uint32_t instance, const ResultCallback callback)

Sequence of drop, slow down, touch down, reel up, lock.

This function is non-blocking. See 'deliver' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

deliver()

Result mavsdk::Winch::deliver(uint32_t instance) const

Sequence of drop, slow down, touch down, reel up, lock.

This function is blocking. See 'deliver_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

hold_async()

void mavsdk::Winch::hold_async(uint32_t instance, const ResultCallback callback)

Engage motor and hold current position.

This function is non-blocking. See 'hold' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

hold()

Result mavsdk::Winch::hold(uint32_t instance) const

Engage motor and hold current position.

This function is blocking. See 'hold_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

retract_async()

void mavsdk::Winch::retract_async(uint32_t instance, const ResultCallback callback)

Return the reel to the fully retracted position.

This function is non-blocking. See 'retract' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

retract()

Result mavsdk::Winch::retract(uint32_t instance) const

Return the reel to the fully retracted position.

This function is blocking. See 'retract_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

load_line_async()

void mavsdk::Winch::load_line_async(uint32_t instance, const ResultCallback callback)

Load the reel with line.

The winch will calculate the total loaded length and stop when the tension exceeds a threshold.

This function is non-blocking. See 'load_line' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

load_line()

Result mavsdk::Winch::load_line(uint32_t instance) const

Load the reel with line.

The winch will calculate the total loaded length and stop when the tension exceeds a threshold.

This function is blocking. See 'load_line_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

abandon_line_async()

void mavsdk::Winch::abandon_line_async(uint32_t instance, const ResultCallback callback)

Spool out the entire length of the line.

This function is non-blocking. See 'abandon_line' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

abandon_line()

Result mavsdk::Winch::abandon_line(uint32_t instance) const

Spool out the entire length of the line.

This function is blocking. See 'abandon_line_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

load_payload_async()

void mavsdk::Winch::load_payload_async(uint32_t instance, const ResultCallback callback)

Spools out just enough to present the hook to the user to load the payload.

This function is non-blocking. See 'load_payload' for the blocking counterpart.

Parameters

• uint32_t instance -
• const ResultCallback callback -

load_payload()

Result mavsdk::Winch::load_payload(uint32_t instance) const

Spools out just enough to present the hook to the user to load the payload.

This function is blocking. See 'load_payload_async' for the non-blocking counterpart.

Parameters

• uint32_t instance -

Returns

 Result - Result of request.

operator=()

const Winch& mavsdk::Winch::operator=(const Winch &)=delete

Equality operator (object is not copyable).

Parameters

• const Winch& -

Returns

 const Winch & -