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Hi all,
I have a turtlebot and RPLidar A2 sensor. I am currently implementing hector slam and I am wondering if it is possible to use the laserScans registered just from the 180degree rotation facing the front of the robot instead of the entire 360deg the RPLidar has to build the map. Is there a way to go about doing that?
Thank you!
Managed to limit the scan by editing the hector mapping source file,hectorMappingRos.cpp. Set a fixed range for [i] - for the scan range and pointcloud data container from 270-360deg and 0 to 90deg. However, this gave rise to an exponential increase in inaccuracies in map building.
what errors did you get? I would expect the accuracy to decrease - less data points - but Hector SLAM will work with XTION - although from experience it's don't like swift angle changes too much as it looses track (Can be helped by adding IMU data)
Yep you will get "SearchDir angle change too large" if the robot rotates too swiftly and there are not enough data points. My 2D RPLidar A2 works fine, but I haven't restricted it
It looks like it's not documented on the laser_pipeline and laser_filters pages, but laser_filters actually contains a LaserScanAngularBoundsFilter which seems to do exactly what you are after (from here):
This is a filter that removes points in a laser scan outside of certain angular bounds.
It shouldn't be too hard to set this up. See #q61538 for a related Q&A.
There is also LaserScanAngularBoundsFilterInPlace to remove an arbitrary chuck, instead of changing the start and stop angles:
https://github.com/ros-perception/las...
Hi,
I can't see how you would this from the existing parameters. I think you could easily hack something like http://wiki.ros.org/depthimage_to_las... , or http://wiki.ros.org/topic_tools/relay to read and or republish laser messages when they're within the desired window angle of measurement.
Mark
Or indeed hack HectorSlam just to process laser range measurements when they're of interest
Asked: 2017-02-20 05:29:00 -0500
Seen: 2,918 times
Last updated: Feb 24 '17
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Try setting the map_update_angle_thresh, laser_min_dist, laser_max_dist params in the hector_slam launch file. Again this is just a logical guess.
Which slam algorithm are you using?
I am using Hector SLAM.
in ros,there is a laserfilter package for it.You can use the laserscanangleboundfilters to do that.