ros 启动建图/导航-- Request for map failed； trying again...

问题描述：在启动ros建图导航时，经常遇到request map类似的报错

[ INFO] [1632648620.520173473]: Requesting the map...
[ WARN] [1632648620.520574107]: Request for map failed; trying again...
[ WARN] [1632648621.022362856]: Request for map failed; trying again...
[ WARN] [1632648621.524463090]: Request for map failed; trying again...

解决：

en…

淦，，，老是忘记开激光雷达节点。。。

hhhha