laser_assembler -> problems with ignore_laser_skew

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Hi,

I have a tilting laser scanner and i am converting the scans to a point cloud with the laser_assembler package. So far everything works fine except of the ignore_laser_skew.

If I deactivate the ignore_laser_skew (set to false), each single point of a scan should be transformed with the tf from that exact time, right? So if the scanner is titling really fastly, I should get somewhat diagonal lines.

Unfortunately, I can't see any difference between ignore_laser_skew=true and ignore_laser_skew=false and so there are quite big errors in the point cloud, if the scanner is tilting fastly.

The tf is updated at 100 Hz, the scans are published at 5 Hz on the topic /tilt_scan. I'm using ros kinetic.

Below you can see the launch file for the laser_assembler and the python script to call the assemble scans service.

Any ideas would could be wrong? Or did i get the purpose of ignore_laser_skew incorrectly? Thanks in advance!

Launch file:

<launch>
  <node type="laser_scan_assembler" pkg="laser_assembler" name="my_assembler">
    <remap from="scan" to="tilt_scan"/>
    <param name="max_scans" type="int" value="1" />
    <param name="tf_cache_time_secs" type="double" value="10" />
    <param name="fixed_frame" type="string" value="base_link" />
    <param name="ignore_laser_skew" type="bool" value="false" />
  </node>
</launch>

script:

#!/usr/bin/env python

import roslib; roslib.load_manifest('laser_assembler')
import rospy; from laser_assembler.srv import *
from sensor_msgs.msg import PointCloud

rospy.init_node("assemble_scan_client")
rate = rospy.Rate(0.5)

while not rospy.is_shutdown():

    rospy.wait_for_service("assemble_scans")

    try:
        assemble_scans = rospy.ServiceProxy('assemble_scans', AssembleScans)
        resp = assemble_scans(rospy.Time(0,0), rospy.get_rostime())
        print "Got cloud with %u points" % len(resp.cloud.points)

        pub=rospy.Publisher('laser_cloud', PointCloud, queue_size=10)
        pub.publish(resp.cloud)

    except rospy.ServiceException, e:
        print "Service call failed: %s"%e

    rate.sleep()