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2015-03-10 18:01:04 -0600 asked a question Coreslam Indigo


is it possible to run coreslam in ROS Indigo and what would be the easiest way to do it for a ROS beginner? I use Ubuntu 14.04

Thank you in advance!

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2015-02-23 16:37:46 -0600 asked a question LaserScan points in laserscan frame


i try to understand how the laserscan points are oriented in the laserscan frame. I publish my own laserscan message which includes 401 scan values in a range from -100 degrees to 100 degrees:

ls_msg.header.frame_id = "scan_frame"
ls_msg.angle_min = -100/180*math.pi
ls_msg.angle_max = 100/180*math.pi
ls_msg.angle_increment = 0.5/180*math.pi
ranges_in_mm = struct.unpack('401H',rcv_str)
ls_msg.ranges = [i/1000.0 for i in ranges_in_mm] # mm to m

But when i look at the laserscan in rviz and set the scan_frame as global fixed frame then the laserscan points start at -180 degrees.

image description

what am i doing wrong?

Thank you in advance!


Ok, i found my mistake. I had to make a division of float values:

ls_msg.angle_min = -100.0/180.0*math.pi
ls_msg.angle_max = 100.0/180.0*math.pi
ls_msg.angle_increment = 0.5/180.0*math.pi
2015-02-19 05:43:16 -0600 asked a question Problem seeing Laserscans in rviz


I am new to ROS and try to work through same of the tutorials. I made the node to publish LaserScan messages from the tutorial and i can see with rostopic echo scan that it is working.

Next i want to visualize it in rviz. So i opened rviz, added the /scan topic and set the fixed frame in Global options to laser_frame. I see that the messages are received and the Status for LaserScan is Ok, but i dont see any points or anything in the map. What am i doing wrong?

I use Indigo with Ubunutu 14.04

Thanks in advance