ROS noetic [turtle1_tf_broadcaster-4] process has died
运行下面的指令
roslaunch turtle_tf turtle_tf_demo.launch
报错：
... logging to /home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/roslaunch-ubun-29906.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://ubun:33955/
SUMMARY
========
PARAMETERS
* /rosdistro: noetic
* /rosversion: 1.15.14
* /scale_angular: 2.0
* /scale_linear: 2.0
* /turtle1_tf_broadcaster/turtle: turtle1
* /turtle2_tf_broadcaster/turtle: turtle2
NODES
/
sim (turtlesim/turtlesim_node)
teleop (turtlesim/turtle_teleop_key)
turtle1_tf_broadcaster (turtle_tf/turtle_tf_broadcaster.py)
turtle2_tf_broadcaster (turtle_tf/turtle_tf_broadcaster.py)
turtle_pointer (turtle_tf/turtle_tf_listener.py)
auto-starting new master
process[master]: started with pid [29914]
ROS_MASTER_URI=http://localhost:11311
setting /run_id to 1d03f5da-9257-11ec-8b40-912958d5c310
process[rosout-1]: started with pid [29924]
started core service [/rosout]
process[sim-2]: started with pid [29931]
process[teleop-3]: started with pid [29932]
process[turtle1_tf_broadcaster-4]: started with pid [29933]
/usr/bin/env: “python”: 没有那个文件或目录
process[turtle2_tf_broadcaster-5]: started with pid [29934]
/usr/bin/env: “python”: 没有那个文件或目录
process[turtle_pointer-6]: started with pid [29937]
/usr/bin/env: “python”: 没有那个文件或目录
Reading from keyboard
---------------------------
Use arrow keys to move the turtle. 'q' to quit.
[turtle1_tf_broadcaster-4] process has died [pid 29933, exit code 127, cmd /opt/ros/noetic/lib/turtle_tf/turtle_tf_broadcaster.py __name:=turtle1_tf_broadcaster __log:=/home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle1_tf_broadcaster-4.log].
log file: /home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle1_tf_broadcaster-4*.log
[turtle2_tf_broadcaster-5] process has died [pid 29934, exit code 127, cmd /opt/ros/noetic/lib/turtle_tf/turtle_tf_broadcaster.py __name:=turtle2_tf_broadcaster __log:=/home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle2_tf_broadcaster-5.log].
log file: /home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle2_tf_broadcaster-5*.log
[turtle_pointer-6] process has died [pid 29937, exit code 127, cmd /opt/ros/noetic/lib/turtle_tf/turtle_tf_listener.py __name:=turtle_pointer __log:=/home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle_pointer-6.log].
log file: /home/mc/.ros/log/1d03f5da-9257-11ec-8b40-912958d5c310/turtle_pointer-6*.log
从报错上来看，是找不到python，
process[turtle1_tf_broadcaster-4]: started with pid [29933]
/usr/bin/env: “python”: 没有那个文件或目录
process[turtle2_tf_broadcaster-5]: started with pid [29934]
/usr/bin/env: “python”: 没有那个文件或目录
process[turtle_pointer-6]: started with pid [29937]
/usr/bin/env: “python”: 没有那个文件或目录
于是我打开
/opt/ros/noetic/lib/turtle_tf/turtle_tf_broadcaster.py
看了一下，确实里面出现的是
#!/usr/bin/env python
使用which python也查不到任何信息，which python3则可以找到：/usr/bin/python3，
于是果断创建快捷链接，
sudo ln -s /usr/bin/python3 /usr/bin/python问题解决。
参考：
[turtle1_tf_broadcaster-4] process has died - ROS Answers: Open Source Q&A Forum