Changing axis of map and odometry about loam_velodyne HOT 8 CLOSED

LOAM switches the axes for each scan before processing the scan. I assume the reason this is done has something to do with the standard coordinate frame from of the velodyne which I believe is z-forward. The x-forward convention is a ROS convention and I believe the ROS driver converts to the scans to the proper ROS convention. I imagine LOAM was written for the velodyne convention, not the ROS convention.

To fix this, change the lines 182-184 to:
point.x = laserCloudIn[i].x;
point.y = laserCloudIn[i].y;
point.z = laserCloudIn[i].z;
link:

Then, since they make an assumption on which axes correspond to the horizontal and vertical axes, you also need to change the following lines:

to:

float angle = std::atan(point.z / std::sqrt(point.y * point.y + point.x * point.x));

and

to

float ori = -std::atan2(point.y, point.x);

That should fix it! Hope this helps.

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You can change Rviz Grid setting to 'XZ'.

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I would have the exact same question as @ashnarayan13!

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@RozDavid , I just had a static transform to handle this. But this doesn't solve the issue of the odometry being in a different frame.
@Zhehua-Hu , I want to change the odometry in the LOAM output

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@ashnarayan13 have you resolved this problem? i'd like to know as i got this problem too

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Hi @ashnarayan13 @w4rlock999 , I succeeded to resolve the convention issue, for changing the odometry frame a few months ago, just forgot to share it with you guys... Really sorry for that. So after including a static broadcaster in the launch file, something like this:
<node pkg="tf2_ros" type="static_transform_publisher" name="loam_broadcaster" args="0 0 0 0.5 0.5 0.5 0.5 world imu_new"/>

You still need the change the frames rotation quaternion with simply changing the axises. Either the imu or aft_mapped, both works similarly, it depends only on your purpose.

You can check my solution here:
https://github.com/RozDavid/loam-segmatch/blob/d1af9f5116e8c6fc5040d6f2f06868e905dcd7f2/src/lib/LaserOdometry.cpp#L908

In this case I included an extra frame for the static transform, then an extra static at the end, but neither of them are essential, only was important for me.

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@RozDavid so, what is the purpose of the static broadcaster you make in the launch file? I dont understand?
And also my laserodometry.cpp already use the orientation you use like this:
laserOdometryTrans.setRotation(tf::Quaternion(-geoQuat.y, -geoQuat.z, geoQuat.x, geoQuat.w));
but it is still moving in the Z directions in the Rviz, the Odometry data (/laser_odom_to_init) also move in Z axis.
could you help me?

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@nickcharron Thank you for the clarity.

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