hector slam turned map during mapping

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I experience some map rotations using hector slam when re-entering a corridor from the other side (cf. screenshots). I use a low frequency (8hz) and 360deg laser up to 70m.

Any ideas what could be the cause? I do not think that it comes from the fact that hector slam has no loop closure algorithm. I guess (hope) that tuning an hector slam parameter would make but which one. I already tried several different configurations but this glitch always appears. I use the default hector_slam package that comes in the ROS indigo. The parameter laser_max_dist does not seem to be taken into account by hector_slam.

Everything seems ok at the beginning. This map correspond to a 50m building approx.

Then, when entering the corridor on the upper left, it is not aligned at all with the first time we mapped it. Corners are not aligned and it is even worse while going ahead in the corridor.

Any idea is welcome.

Thanks