tf_example_node.cpp
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00001 /*
00002 Copyright (c) 2011-2014, Mathieu Labbe - IntRoLab - Universite de Sherbrooke
00003 All rights reserved.
00004 
00005 Redistribution and use in source and binary forms, with or without
00006 modification, are permitted provided that the following conditions are met:
00007     * Redistributions of source code must retain the above copyright
00008       notice, this list of conditions and the following disclaimer.
00009     * Redistributions in binary form must reproduce the above copyright
00010       notice, this list of conditions and the following disclaimer in the
00011       documentation and/or other materials provided with the distribution.
00012     * Neither the name of the Universite de Sherbrooke nor the
00013       names of its contributors may be used to endorse or promote products
00014       derived from this software without specific prior written permission.
00015 
00016 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
00017 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
00018 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
00019 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY
00020 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
00021 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00022 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
00023 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00024 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00025 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00026 */
00027 
00028 #include <ros/ros.h>
00029 #include <tf/transform_listener.h>
00030 #include <find_object_2d/ObjectsStamped.h>
00031 #include <QtCore/QString>
00032 
00033 class TfExample
00034 {
00035 public:
00036         TfExample() :
00037                 mapFrameId_("/map"),
00038                 objFramePrefix_("object")
00039         {
00040                 ros::NodeHandle pnh("~");
00041                 pnh.param("map_frame_id", mapFrameId_, mapFrameId_);
00042                 pnh.param("object_prefix", objFramePrefix_, objFramePrefix_);
00043 
00044                 ros::NodeHandle nh;
00045                 subs_ = nh.subscribe("objectsStamped", 1, &TfExample::objectsDetectedCallback, this);
00046         }
00047 
00048         // Here I synchronize with the ObjectsStamped topic to
00049         // know when the TF is ready and for which objects
00050         void objectsDetectedCallback(const find_object_2d::ObjectsStampedConstPtr & msg)
00051         {
00052                 if(msg->objects.data.size())
00053                 {
00054                         for(unsigned int i=0; i<msg->objects.data.size(); i+=12)
00055                         {
00056                                 // get data
00057                                 int id = (int)msg->objects.data[i];
00058                                 std::string objectFrameId = QString("%1_%2").arg(objFramePrefix_.c_str()).arg(id).toStdString(); // "object_1", "object_2"
00059 
00060                                 tf::StampedTransform pose;
00061                                 tf::StampedTransform poseCam;
00062                                 try
00063                                 {
00064                                         // Get transformation from "object_#" frame to target frame "map"
00065                                         // The timestamp matches the one sent over TF
00066                                         tfListener_.lookupTransform(mapFrameId_, objectFrameId, msg->header.stamp, pose);
00067                                         tfListener_.lookupTransform(msg->header.frame_id, objectFrameId, msg->header.stamp, poseCam);
00068                                 }
00069                                 catch(tf::TransformException & ex)
00070                                 {
00071                                         ROS_WARN("%s",ex.what());
00072                                         continue;
00073                                 }
00074 
00075                                 // Here "pose" is the position of the object "id" in "/map" frame.
00076                                 ROS_INFO("Object_%d [x,y,z] [x,y,z,w] in \"%s\" frame: [%f,%f,%f] [%f,%f,%f,%f]",
00077                                                 id, mapFrameId_.c_str(),
00078                                                 pose.getOrigin().x(), pose.getOrigin().y(), pose.getOrigin().z(),
00079                                                 pose.getRotation().x(), pose.getRotation().y(), pose.getRotation().z(), pose.getRotation().w());
00080                                 ROS_INFO("Object_%d [x,y,z] [x,y,z,w] in \"%s\" frame: [%f,%f,%f] [%f,%f,%f,%f]",
00081                                                 id, msg->header.frame_id.c_str(),
00082                                                 poseCam.getOrigin().x(), poseCam.getOrigin().y(), poseCam.getOrigin().z(),
00083                                                 poseCam.getRotation().x(), poseCam.getRotation().y(), poseCam.getRotation().z(), poseCam.getRotation().w());
00084                         }
00085                 }
00086         }
00087 
00088 private:
00089         std::string mapFrameId_;
00090         std::string objFramePrefix_;
00091     ros::Subscriber subs_;
00092     tf::TransformListener tfListener_;
00093 };
00094 
00095 int main(int argc, char * argv[])
00096 {
00097     ros::init(argc, argv, "tf_example_node");
00098 
00099     TfExample sync;
00100     ros::spin();
00101 }


find_object_2d
Author(s): Mathieu Labbe
autogenerated on Fri Feb 12 2016 01:18:17