grid

目录

0 前言

1 下载编译

1.1 下载

1.2 编译

2  从点云数据包创建栅格地图

2.1 ImportError: cannot import name perf_counter

ImportError: dynamic module does not define module export function (PyInit__tf2)

2.2 目录不对

2.3 缺包

2.4 NameError: name 'reload' is not defined

2.5 运行效果

---

0 前言

        github仓地址：https://github.com/lukovicaleksa/grid-mapping-in-ROS

        grid-mapping-in-ROS用python写的，用cmake编译配置了ros接口

         本次使用环境：ubuntu18.04，python2.7

1 下载编译 1.1 下载

mkdir -p grid_mapping_in_ros_ws/src
cd grid_mapping_in_ros_ws/src
git clone https://github.com/lukovicaleksa/grid-mapping-in-ROS.git

1.2 编译

        到工作空间目录下grid_mapping_in_ros_ws。

catkin_make

        因为是python文件，一般编译不会报错

2  从点云数据包创建栅格地图

        python文件地址：/home/meng/Desktop/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/scripts/create_from_rosbag.py

cd /home/meng/Desktop/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/scripts
python create_from_rosbag.py

        下面按顺序记录报错及解决办法

2.1 ImportError: cannot import name perf_counter

        报错原因：python2.7（ubuntu16和ubuntu18自带的python版本）的time这个模块没有perf_counter这个函数。

        解决办法：用time.clock()函数替换time.perf_counter()函数；具体两个函数区别，大家可以查一查

#注：time.clock()这个函数好像在python3.4之后被弃用了

        替换create_from_rosbag.py文件对应位置如下：

# from time import perf_counter  8行
from time import time


		# Init time  75行
		t_start = time()
		# t_start = perf_counter()


			t_step = time() #190多行
			# t_step = perf_counter()

------------------------------------------------------------------------------------------------------------------------

        !!!此外 python3.6、python3.7版本的time模块会有这个perf_counter()函数，但这里不要替换python版本；我试着替换为python3.7版本，这个报错没有了，但后面因为需要使用ros，而ros与python2.7版本紧密结合，会让系统出现多个python版本，引发下面的错误

ImportError: dynamic module does not define module export function (PyInit__tf2)

--报错原因是系统出现了多个python版本

Failed to load Python extension for LZ4 support. LZ4 compression will not be available.
Traceback (most recent call last):
  File "create_from_rosbag.py", line 25, in 
    from utils import *
  File "/home/meng/ideas/auto_resolution_map/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/scripts/utils.py", line 5, in 
    from tf.transformations import euler_from_quaternion, quaternion_from_euler
  File "/opt/ros/melodic/lib/python2.7/dist-packages/tf/__init__.py", line 30, in 
    from tf2_ros import TransformException as Exception, ConnectivityException, LookupException, ExtrapolationException
  File "/opt/ros/melodic/lib/python2.7/dist-packages/tf2_ros/__init__.py", line 38, in 
    from tf2_py import *
  File "/opt/ros/melodic/lib/python2.7/dist-packages/tf2_py/__init__.py", line 38, in 
    from ._tf2 import *
ImportError: dynamic module does not define module export function (PyInit__tf2)

在下面博客得到系统有多个版本这个信息

https://blog.csdn.net/pangweijian/article/details/104915171

 ------------------------------------------------------------------------------------------------------------------------

2.2 目录不对

        修改目录为自己的目录，示例如下：

# SCRIPTS_PATH = '/home/maestro/catkin_ws/src/grid_mapping/scripts'
# BAG_FILE_PATH = '/home/maestro/catkin_ws/src/grid_mapping/bagfiles'
# MAPS_PATH = '/home/maestro/catkin_ws/src/grid_mapping/maps'

SCRIPTS_PATH = '/home/meng/Desktop/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/scripts'
BAG_FILE_PATH = '/home/meng/Desktop/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/bagfiles'
MAPS_PATH = '/home/meng/Desktop/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/maps'

2.3 缺包

        见python(4):ModuleNotFoundError: No module named ‘*‘_biter0088的博客-CSDN博客

的1 rosbag相关

2.4 NameError: name 'reload' is not defined

        如果遇到这个错误，修改这个报错里面最后一个文件，修改参考如下：

meng@meng:~/ideas/auto_resolution_map/grid_mapping_in_ros_ws/src/grid-mapping-in-ROS/scripts$ python create_from_rosbag.py 
Traceback (most recent call last):
  File "create_from_rosbag.py", line 3, in 
    import rospy
  File "/opt/ros/melodic/lib/python2.7/dist-packages/rospy/__init__.py", line 49, in 
    from .client import spin, myargv, init_node, \
  File "/opt/ros/melodic/lib/python2.7/dist-packages/rospy/client.py", line 52, in 
    import roslib
  File "/opt/ros/melodic/lib/python2.7/dist-packages/roslib/__init__.py", line 53, in 
    import roslib.stacks  # noqa: F401, I100
  File "/opt/ros/melodic/lib/python2.7/dist-packages/roslib/stacks.py", line 45, in 
    import roslib.packages
  File "/opt/ros/melodic/lib/python2.7/dist-packages/roslib/packages.py", line 44, in 
    reload(sys)
NameError: name 'reload' is not defined

sudo gedit /opt/ros/melodic/lib/python2.7/dist-packages/roslib/packages.py

        注释掉原来的import(sys)，加上python2.x对应的import sys的方式即可

####hxz   python 2.x
# -*- coding:utf-8 -*-
import sys
reload(sys)
sys.setdefaultencoding('utf-8')
####hxz

import os
import stat
#import sys  #hxz
from subprocess import PIPE
from subprocess import Popen

参考链接:https://blog.csdn.net/lxw1844912514/article/details/100029431

2.5 运行效果