roscore出错 rosversion

错误信息：


Cannot locate [roslaunch]Invalid <param> tag: Cannot load command parameter [rosversion]: command [rosversion roslaunch] returned with code [1].

输入：rosversion roslaunch，rosversion ros都出错cannot locate
原因：rosversion 版本错误，属于python-rospkg的一部分

sudo apt-get install python-rospkg

即可. easy_install版本太旧，不要




原答案：

The poblem you have is around rosversion. This should be the correct output:

$ rosversion roslaunch 1.9.39

rosversion is part of python-rospkg. So you can initially make sure that this is up to date, and no old easy_install version of rospkg luring in /usr/local/lib/python2.7/dist-packages

I'd guess an outdated version of rospkg is a likely culprit for your error

http://answers.ros.org/question/51878/launching-roscore-in-groovy-fails/