Class SensorModel

Inheritance Relationships

Derived Type

Class Documentation

class SensorModel

The interface definition for sensor model plugins in the fuse ecosystem.

A sensor model plugin is responsible for generating new constraints and passing them along to the optimizer, where the actual sensor fusion takes place. This class defines the basic interface between the sensor model and the optimizer. If you are developing your own sensor model, look at the AsyncSensorModel class, as this provides additional features that make the sensor model act similar to a ROS node or nodelet.

During the initialize() call, the optimizer will provide a transaction callback. This function serves the same basic purpose as publishing a Transaction using a standard ROS publisher. Derived classes should call this function whenever they are ready to send a fuse_core::Transaction object to the optimizer. This function will be called in the SensorModel’s thread. The optimizer implementation should ensure that this callback is safe to execute in this thread. The optimizer should also ensure the callback executes quickly so that it will not block execution in the SensorModel.

Subclassed by fuse_core::AsyncSensorModel

Public Functions

virtual ~SensorModel() = default

Destructor.

inline virtual void graphCallback(Graph::ConstSharedPtr)

Function to be executed whenever the optimizer has completed a Graph update.

This method will be called by the optimizer, in the optimizer’s thread, after each Graph update is complete. This generally means that new variables have been inserted into the Graph, and new optimized values are available. To simplify synchronization between the sensor models and other consumers of Graph data, the provided Graph object will never be updated by anyone. Thus, only read access to the Graph is provided. Information may be accessed or computed, but it cannot be changed. The optimizer provides the sensors with Graph updates by sending a new Graph object, not by modifying this Graph object.

Parameters:

graph – [in] A read-only pointer to the graph object, allowing queries to be performed whenever needed.

virtual void initialize(node_interfaces::NodeInterfaces<ALL_FUSE_CORE_NODE_INTERFACES> interfaces, const std::string &name, TransactionCallback transaction_callback) = 0

Perform any required post-construction initialization, such as subscribing to topics or reading from the parameter server.

This will be called on each plugin after construction, and after the ROS node has been initialized. Plugins are encouraged to subnamespace any of their parameters to prevent conflicts and allow the same plugin to be used multiple times with different settings and topics.

Parameters:

  • name – [in] A unique name to give this plugin instance

  • transaction_callback – [in] The function to call every time a transaction is published

virtual const std::string &name() const = 0

Get the unique name of this sensor.

inline virtual void start()

Function to be executed whenever the optimizer is ready to receive transactions.

This method will be called by the optimizer, in the optimizer’s thread, once the optimizer has been initialized and is ready to receive transactions. It may also be called as part of a stop-start cycle when the optimizer has been requested to reset itself. This allows the sensor model to reset any internal state before the optimizer begins processing after a reset.

The sensor model must not send any transactions to the optimizer before start() is called.

inline virtual void stop()

Function to be executed whenever the optimizer is no longer ready to receive transactions.

This method will be called by the optimizer, in the optimizer’s thread, before the optimizer shutdowns. It may also be called as part of a stop-start cycle when the optimizer has been requested to reset itself. This allows the sensor model to reset any internal state before the optimizer begins processing after a reset.

The sensor model must not send any transactions to the optimizer after stop() is called.

Protected Functions

SensorModel() = default

Default Constructor.