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LaserScan in TurtleBot examples

Asked by angelos.p on 24 Jun 2015
Latest activity Edited by angelos.p on 25 Jun 2015
Dear friends,
I tried to experiment with the TurtleBot examples in the related robotics toolbox. The issue that I have is that my laserscan is not similar to the example's picture (Exploring Basic Behavior of the TurtleBot). It is just a line
I don't think that is reasonable for a simulation environment like that
Is something wrong? I just followed the example like
laser = rossubscriber('/scan');
scan = receive(laser,3)
plot(scan);

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1 Answer

Answer by Sebastian Castro on 24 Jun 2015

The commands certainly look correct. Have you tried changing the maximum scan range to a nondefault value? For example:
plot(scan,'MaximumRange',10);
Also, what happens as you move/rotate the robot? Do the plots change or stay the same?
- Sebastian

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Dear Sebastian, thanks for the help. Unfortunately, the plot with changed MaximumRange gave the exactly the same results.
I tried the same commands with the "Gazebo Playground" launch file but noting interesting.
and when I executed the "Obstacle Avoidance using TartleBot" example I got the same bar in the front just moving...
So something goes wrong with the scanning, it cann't be a single line.
The details of my scene looks like...(if this can help)
>> scan = receive(laser,3)
scan =
ROS LaserScan message with properties:
MessageType: 'sensor_msgs/LaserScan'
Header: [1x1 Header]
AngleMin: -0.5216
AngleMax: 0.5243
AngleIncrement: 0.0016
TimeIncrement: 0
ScanTime: 0.0330
RangeMin: 0.4500
RangeMax: 10
Ranges: [640x1 single]
Intensities: [0x1 single]
Use showdetails to show the contents of the message
>> showdetails(scan)
AngleMin : -0.5215678811
AngleMax : 0.5242763162
AngleIncrement : 0.00163668883
TimeIncrement : 0
ScanTime : 0.03299999982
RangeMin : 0.4499999881
RangeMax : 10
Ranges : [1.152452707, 1.151556969, 1.150663376, 1.14977181, 1.147995353, 1.154250622, 1.155152678, ]
Intensities : []
Header
Seq : 205
FrameId : /camera_depth_frame
Stamp
Sec : 184
Nsec : 840000000

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