File "/opt/ros/melodic/lib/turtle_tf/turtle_tf_broadcaster.py", line 37, in <module> import tf

小灰灰 2023-06-30 01:36 11阅读 0赞

*  **系统**:  U b u n t u 18.04 \\color\{blue\}\{Ubuntu18.04\} Ubuntu18.04
 *  **ROS版本**： M e l o d i c \\color\{blue\}Melodic Melodic
 *  **系统默认Python版本**：Python3(Anaonda)
 *  **遇到问题**：执行`roslaunch turtle_tf turtle_tf_demo.launch`报错。
 *  **报错内容如下**：

> Traceback (most recent call last):  
> File “/opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_broadcaster.py”, line 37, in  
> import tf  
> 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)  
> Traceback (most recent call last):  
> File “/opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_broadcaster.py”, line 37, in  
> import tf  
> 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)  
> Traceback (most recent call last):  
> File “/opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_listener.py”, line 37, in  
> import tf  
> 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)  
> \[turtle1\_tf\_broadcaster-3\] process has died \[pid 17180, exit code 1, cmd /opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_broadcaster.py \_\_name:=turtle1\_tf\_broadcaster \_\_log:=/home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle1\_tf\_broadcaster-3.log\].  
> log file: /home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle1\_tf\_broadcaster-3\*.log  
> \[turtle2\_tf\_broadcaster-4\] process has died \[pid 17187, exit code 1, cmd /opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_broadcaster.py \_\_name:=turtle2\_tf\_broadcaster \_\_log:=/home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle2\_tf\_broadcaster-4.log\].  
> log file: /home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle2\_tf\_broadcaster-4\*.log  
> \[turtle\_pointer-5\] process has died \[pid 17188, exit code 1, cmd /opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_listener.py \_\_name:=turtle\_pointer \_\_log:=/home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle\_pointer-5.log\].  
> log file: /home/philtell/.ros/log/5a5570ca-35d5-11ea-92de-c83dd4ac14c9/turtle\_pointer-5\*.log  
> \[teleop-2\] killing on exit  
> \[sim-1\] killing on exit  
> shutting down processing monitor…  
> … shutting down processing monitor complete

*  分析：  
    遇到这么长的问题，先别慌，从第一行来分析：

> File “/opt/ros/melodic/lib/turtle\_tf/turtle\_tf\_broadcaster.py”, line 37, in  
> import tf

显然是导入模块失败，截止到当前时间：2020年01月13日15:57:04，ROS系统中的tf模块有两个版本。  
出现这个问题有两种可能:

1.  一个是你的ROS系统中没有tf
2.  你的py文件导入的tf执行的python版本是3，不是2

出现问题1好解决，去官方网站安装就行。  
怎么看是否是问题1或者2呢？  
首先在`terminal`中分别运行`python`，`python2`,并在python环境中输入`import tf`,如果在python2中没有报错，就说明已经安装了tf,如果在python中报错，而且报的错误和直接执行`roslaunch turtle_tf turtle_tf_demo.launch`报的错误一样，那么就说明py默认指定的是python3,只需要找到相应的python脚本文件执行更改就可以了，操作如下所示：

操 作 前 : \\color\{pink\}操作前: 操作前:  
![在这里插入图片描述][20200113160432444.png]  
 操 作 后 : \\color\{cyan\}操作后: 操作后:  
![在这里插入图片描述][2020011316045996.png]

[20200113160432444.png]: https://img-blog.csdnimg.cn/20200113160432444.png
[2020011316045996.png]: https://img-blog.csdnimg.cn/2020011316045996.png