Hello, I am trying to use the point cloud on laser data... but the transform/frame stuff is messing with me.  I want to be able to get points with reference to the robot and points with reference to the fixed frame map.  Currently I am looking up the transform between base_laser_link and odom which outputs points in a manner that is beyond my spatial understanding.  Here is the code:<div>
<br></div><div><div>static tf::TransformListener tf_listener;</div><div> <span class="Apple-tab-span" style="white-space:pre">	</span>//const sensor_msgs::LaserScan::ConstPtr msg_in_myframe = tf_listener.transformPoint(</div>
<div>  // Get the transform from the laser frame to the odometry frame</div><div>  tf::StampedTransform transform;</div><div>  try {</div><div>    tf_listener.lookupTransform(msg-&gt;header.frame_id, &quot;odom&quot;,  ros::Time(), transform);</div>
<div>    </div><div>    // Turn the laser scan into a point cloud, in the odom coordinate frame</div><div>    sensor_msgs::PointCloud point_cloud;</div><div>    laser_projection.transformLaserScanToPointCloud(&quot;odom&quot;, *msg, point_cloud, tf_listener);</div>
<div>    </div><div>    for(vector&lt;geometry_msgs::Point32&gt;::iterator it = point_cloud.points.begin(); it != point_cloud.points.end(); ++it)</div><div>      ss &lt;&lt; it-&gt;x &lt;&lt; &#39; &#39;&lt;&lt; it-&gt;y &lt;&lt; endl;</div>
<div><br></div><div>  } catch (tf::TransformException &amp;ex){</div><div>    ROS_ERROR(&quot;%s&quot;, ex.what());</div><div>  }</div><br>-- <br>Todd Anderson<br>(919) 710-0546<br>Washington University in St. Louis Class of 2011<br>
School of Engineering and Applied Sciences<br>
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