JointStateSubscriber QML Type

Subscribes to sensor_msgs::msg::JointState messages — This is a message that holds data to describe the state of a set of torque controlled joints. More...

• List of all members, including inherited members

Properties

• effort : list<double>
• header : header
• message : jointState
• name : list<string>
• position : list<double>
• velocity : list<double>

Signals

• messageReceived(jointState msg)

Detailed Description

The state of each joint (revolute or prismatic) is defined by:

• the position of the joint (rad or m),
• the velocity of the joint (rad/s or m/s) and
• the effort that is applied in the joint (Nm or N).

Each joint is uniquely identified by its name The header specifies the time at which the joint states were recorded. All the joint states in one message have to be recorded at the same time.

This message consists of a multiple arrays, one for each part of the joint state. The goal is to make each of the fields optional. When e.g. your joints have no effort associated with them, you can leave the effort array empty.

All arrays in this message should have the same size, or be empty. This is the only way to uniquely associate the joint name with the correct states.

JointStateSubscriber receives jointState values from a ROS 2 topic. Set the topic and node properties, then connect to the messageReceived() signal.

See also JointStatePublisher and jointState.

Property Documentation

effort : list<double>

The effort field of the last received message. Updated whenever a new message arrives. effortChanged is emitted on every update.

header : header

The header field of the last received message. Updated whenever a new message arrives. headerChanged is emitted on every update.

message : jointState

The last message received on topic. Updated whenever a new message arrives.

name : list<string>

The name field of the last received message. Updated whenever a new message arrives. nameChanged is emitted on every update.

position : list<double>

The position field of the last received message. Updated whenever a new message arrives. positionChanged is emitted on every update.

velocity : list<double>

The velocity field of the last received message. Updated whenever a new message arrives. velocityChanged is emitted on every update.

Signal Documentation

messageReceived(jointState msg)

Emitted when a new jointState arrives on topic. msg contains the received value.