Cartographer连接激光-hokuyo UTM-30LX

系统环境：

64位/ubuntu14 /ros-indogo

一、在ros中安装hokuyo node:

1）连接激光到虚拟机，打开一个terminal ,下载激光的节点包 # sudo apt-get install ros-indigo-hokuyo-node

2)接下来配置激光节点，首先确保虚拟机菜单中虚拟机-可移动设备已经接上URG，然后可以开始配置：

# cd /etc/udev/rules.d

#cd touch 50-laser.rules

#sudo gedit 50-laserr.rules

在文件中添加以下内容： KERNEL="ttyACM[0-9]*" ，MODE="0777"

重启.rules使之生效：

#sudo /etc/init.d/udev restart

检查权限#ls -al /dev/ttyACM0 如果显示 crw-rw 则输入 #sudo chmod a+rw /dev/tty/ACM0 权限应为 crw-rw-rw.....

这样激光就在ros中可以使用啦！接下来下载slam的程序包

二、安装谷歌slam Cartographer_ros

源码安装地址： https://google-cartographer-ros.readthedocs.io/en/latest/

                # Install wstool and rosdep.
                  sudo apt-get update
                 sudo apt-get install -y python-wstool python-rosdep ninja-build

# Create a new workspace in 'catkin_ws'.
mkdir catkin_ws

cd catkin_ws
wstool init src

                # Merge the cartographer_ros.rosinstall file and fetch code for dependencies.
                wstool merge -t src https://raw.githubusercontent.com/googlecartographer/cartographer_ros/master/cartographer_ros.rosinstall
                wstool update -t src

               # Install deb dependencies.
                rosdep init
               rosdep update   #（多试几遍，早晨容易成功）
              rosdep install --from-paths src --ignore-src --rosdistro=${ROS_DISTRO} -y

              # Build and install.
                catkin_make_isolated --install --use-ninja （#这边容易出错）
                source install_isolated/setup.bash

值得注意的是，cartographer的包一直在更新，很多人运行Catkin_make_isolated时很容易报错，说找不到ceres库，有人说用VPN或者改IP地址等等，在此贴上几个博客，以供参考：

http://www.cnblogs.com/wenhust/p/6112845.html

安装成功后，就可以跑激光啦！

三、北洋激光连接谷歌slam

在launch文件夹下新建一个文件demo_hokuyo.launch ,本人建议先拷贝一个其他的demo的launch（这样里面还是彩色的，不然是黑白的），然后再自己改个名字，再在文件中加入以下内容：

这其实就是改了 from scan to scan

然后再上一层文件夹中寻找配置文件夹，打开，新建一个demo_hokuyo.lua的文件，写入以下内容：

-- Copyright 2016 The Cartographer Authors
--
-- Licensed under the Apache License, Version 2.0 (the "License");
-- you may not use this file except in compliance with the License.
-- You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.

include "map_builder.lua"

options = {
map_builder = MAP_BUILDER,
sensor_bridge={
horizontal_laser_min_range=0.,
horizontal_laser_max_range=30.,
horizontal_laser_missing_echo_ray_length=1.,
constant_odometry_translational_variance=0.,
constant_odometry_rotational_variance=0.,

},
map_frame = "map",
tracking_frame = "laser",
published_frame = "laser",
odom_frame = "odom",
provide_odom_frame = true,
use_odometry = false,
use_laser_scan = true,
use_multi_echo_laser_scan = false,
num_point_clouds = 0,
lookup_transform_timeout_sec = 0.2,
submap_publish_period_sec = 0.3,
pose_publish_period_sec = 5e-3,
}

MAP_BUILDER.use_trajectory_builder_2d = true

TRAJECTORY_BUILDER_2D.laser_min_range = 0.1
TRAJECTORY_BUILDER_2D.laser_max_range = 30.
TRAJECTORY_BUILDER_2D.laser_missing_echo_ray_length = 1.
TRAJECTORY_BUILDER_2D.use_imu_data = false
TRAJECTORY_BUILDER_2D.use_online_correlative_scan_matching = true

SPARSE_POSE_GRAPH.optimization_problem.huber_scale = 1e2

return options

（经过比对发现 .rviz文件不用改）

这样就完成啦！重新make 一下，再source一下，运行 roslaunch cartographer_ros demo_hokuyo.launch 就可以看到激光建地图啦！

如果要跑bag文件，请参考谷歌原地址。