发布：

include

<

tf/transform_broadcaster.h

>


定义发布者　　 static tf::TransformBroadcaster br;

定义转换 tf::Transform transform;

设置平移转换　 transform.setOrigin( tf::Vector3(msg->x, msg->y, 0.0);

定义四元数　 tf::Quaternion q;

设置四元数　　　 q.setRPY(0, 0, msg->theta);

设置旋转转换　　 transform.setRotation(q);

发布tf转换 br.sendTransform(tf::StampedTransform(transform, ros::Time::now(), “world”, turtle_name));

监听：

include

<

tf/transform_listener.h

>


设置监听　　tf::TransformListener listener;

定义转换 tf::StampedTransform transform;

监听转换 listener.lookupTransform(“/turtle2”, “/turtle1”, ros::Time(0), transform);

Here, the real work is done, we query the listener for a specific transformation. Let’s take a look at the four arguments:

1.We want the transform from frame /turtle1 to frame /turtle2.

2.The time at which we want to transform. Providing ros::Time(0) will just get us the latest available transform.

3.The object in which we store the resulting transform.

try{

ros::Time now = ros::Time::now();

listener.waitForTransform(“/turtle2”, “/turtle1”,

now, ros::Duration(3.0));

listener.lookupTransform(“/turtle2”, “/turtle1”,

now, transform);

}

The waitForTransform() takes four arguments:

1. Wait for the transform from this frame…

2. … to this frame,

3. at this time, and

4. timeout: don’t wait for longer than this maximum duration

try{

ros::Time now = ros::Time::now();

ros::Time past = now – ros::Duration(5.0);

listener.waitForTransform(“/turtle2”, now,

“/turtle1”, past,

“/world”, ros::Duration(1.0));

listener.lookupTransform(“/turtle2”, now,

“/turtle1”, past,

“/world”, transform);

}

The advanced API for lookupTransform() takes six arguments:

1. Give the transform from this frame,

2. at this time …

3. … to this frame,

4. at this time.

5. Specify the frame that does not change over time, in this case the “/world” frame, and

6. the variable to store the result in.

添加一个frame：

include

<

ros/ros.h

>


include

<

tf/transform_broadcaster.h

>


int main(int argc, char** argv){

ros::init(argc, argv, “my_tf_broadcaster”);

ros::NodeHandle node;

tf::TransformBroadcaster br;

tf::Transform transform;

ros::Rate rate(10.0);

while (node.ok()){

transform.setOrigin( tf::Vector3(0.0, 2.0, 0.0) );

transform.setRotation( tf::Quaternion(0, 0, 0, 1) );

br.sendTransform(tf::StampedTransform(transform, ros::Time::now(), “turtle1”, “carrot1”));

rate.sleep();

}

return 0;

};