00001 /* 00002 * Copyright (c) 2008, Willow Garage, Inc. 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 * 00008 * * Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * * Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * * Neither the name of the Willow Garage, Inc. nor the names of its 00014 * contributors may be used to endorse or promote products derived from 00015 * this software without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 00018 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00019 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00020 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 00021 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 00022 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 00023 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00024 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00025 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 00026 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 00027 * POSSIBILITY OF SUCH DAMAGE. 00028 * 00029 */ 00030 00031 #include "odometer.h" 00032 00033 namespace graph_slam 00034 { 00035 00036 Odometer::Odometer (tf::TransformListener* tf, const std::string& base_frame, 00037 const std::string& fixed_frame, const ros::Duration& timeout) : 00038 wait_inc_(5.0), tf_(tf), base_frame_(base_frame), fixed_frame_(fixed_frame) 00039 { 00040 reset(timeout); 00041 } 00042 00043 void Odometer::reset (const ros::Time& t, const ros::Duration& timeout) 00044 { 00045 const ros::Duration inc = timeout < wait_inc_ ? timeout : wait_inc_; 00046 for (unsigned i=0; i<ceil(timeout.toSec()/inc.toSec()); i++) { 00047 if (tf_->waitForTransform(fixed_frame_, base_frame_, t, inc)) 00048 break; 00049 ROS_INFO_STREAM ("Waiting for transform from " << base_frame_ << " to " << fixed_frame_ << 00050 " at " << t); 00051 } 00052 // If we didn't find a transform, a tf exception will be thrown on the next step 00053 00054 tf::StampedTransform trans; 00055 tf_->lookupTransform(fixed_frame_, base_frame_, t, trans); 00056 reference_pose_.setData(trans); // Slicing happens here 00057 reference_pose_.stamp_ = trans.stamp_; 00058 reference_pose_.frame_id_ = fixed_frame_; 00059 } 00060 00061 ros::Time Odometer::reset (const ros::Duration& timeout) 00062 { 00063 reset (ros::Time(), timeout); 00064 return reference_pose_.stamp_; 00065 } 00066 00067 tf::Pose Odometer::getDisplacement (const ros::Time& t) 00068 { 00069 tf::StampedTransform trans; 00070 tf_->lookupTransform(fixed_frame_, base_frame_, t, trans); 00071 return reference_pose_.inverseTimes(trans); 00072 } 00073 00074 00075 } // namespace graph_slam