17
votes
Why do people use camera instead of laser sensor for robot navigation?
A 3D laser range finder or LIDAR such as the one on the Google Car is far more expensive than a camera. The other reason is that while in case of a LIDAR the distance of every pixel is available, the ...
- 633
5
votes
Accepted
Are there any advantages to using a LIDAR for SLAM vs a standard RGB camera?
My question: are there cases where you'd still need a LIDAR or can
this expensive sensor be replaced with a standard camera? ...
A each one of them has its advantages/disadvantages. Thus in some ...
- 319
5
votes
Do multiple LIDAR systems in same area interfere?
Based on two different company's sensors for use in autonomous cars - yes they do interfere. And honestly, I am not sure what is going to happen when you have 30 cars in an intersection, the noise ...
- 51
5
votes
What is the definition of the contents of PointCloud2?
I get why you are confused.
Looking at the definition of PointCloud2, you see that the field that holds the "actual" point cloud data is a 1-dimensional array. Now,...
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4
votes
Why do people use camera instead of laser sensor for robot navigation?
In addition to those points in Bence's answer, cameras can:
Calculate many complex features that result in very robust matching between frames, and object recognition
High angular resolution (typical ...
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4
votes
How does 3D Lidar work?
Lidar, sonar, and radar all work generally the same:
Emit a pulse. For radar, this means briefly energizing an antenna. For sonar, it means briefly energizing a sound transducer/speaker. For lider, ...
- 15.9k
4
votes
What is the definition of the contents of PointCloud2?
I totally agree that the documentation is poor and it took me quite some time to understand what is going on.
I recorded a rosbag for "velodyne_points" topic using a Velodyne VLP-16. The ...
- 41
3
votes
Accepted
Iterative Closest Point for 2-D LIDAR Data
You can use 3D feature descriptors here to register two point clouds. I've personally used two most recent ones that performed well enough for a similar application.
Following are the references to ...
- 153
3
votes
Accepted
Do multiple LIDAR systems in same area interfere?
One could use lasers with slightly different wave length - just as different channels for Wi-Fi signal. Also there could be used some kind of wave modulation... but I don't think LIDARs use such ...
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3
votes
Why do people use camera instead of laser sensor for robot navigation?
navigation in urban environments
Depending on the laser, there might be legal constraints on where you can use it. Running around town throwing laser rays around might require special permission/...
- 1,425
3
votes
How to cope with an optical window limitation on 2D LiDAR?
The answer by @nathangeorge1 is valid for the case of not hitting the legs of the chair.
However, you are faced with limited sensor input. This is the case for most robots, even people need to turn ...
3
votes
How come LIDAR is not commonly used for indoor navigation?
I think LiDAR is common for indoor navigation. Definitely, LiDAR is the easiest and accurate solution for indoor navigation or SLAM. Many commercial robot vacuums are already in use of LiDAR for ...
- 1,527
3
votes
Data collected from ROS
As Ben noticed, you may want to elaborate on your question, but in general data collection in ROS is performed using tools from the rosbag package.
As you'll find when you read the documentation, ...
- 1,308
3
votes
Extract laser scan from a map and known location
You can do it manually with a protractor and straight edge - put the center of your protractor on the scanner center, align your protractor's zero-angle mark to the scanner zero, then mark off ticks ...
- 15.9k
3
votes
Transform problem with rviz map display when using the SLAMTEC Mapper M2M2 with ROS
No transform from [/slamware_map] to [slamware_map].
I'm not familiar with Slamware in particular, but I can tell you what the error means. RViz is trying to display data that has a ...
- 206
2
votes
Lidar problems in a multi-robot setup
I wouldn't recommend using sensors with different laser frequencies either, because that likely means using an entirely different product, with different accuracy and other properties.
don't tilt, ...
- 1,425
2
votes
Determining position from a 2D map and LIDAR
I just wanted add on to both user12895 and AL-ROBOT's answers.
Based on experience:
What you need is an (Iterative Point Cloud) ICP algorithm.
Do not worry, if the robot cannot detect the entire ...
- 183
2
votes
Determining position from a 2D map and LIDAR
1- Of course you don't have perfect matches
2- ICP is not used for localization, it is used to calculate the transformation the robot's pose has undergone (T+R)
3- To localize your robot, you would ...
- 319
2
votes
Why do people use camera instead of laser sensor for robot navigation?
Like other already answered. Cameras typically are much cheaper than Laser Range Finders.
When you talk about camera you mean the 2D cameras isn't it? There are some 3D cameras like the ifm O3D3xx ...
- 21
2
votes
Resources for object detection with 2D Laser Scanner (planar only)
I think you can divide your problem into two subproblems:
1) Partition your 2D scan into segments/clusters which represent single objects. A basic algorithm could be:
Start at first laser reading ...
- 21
2
votes
Accepted
Multiple Line Estimation
You can start by using split-and-merge segmentation algorithm.
There are many algorithms available A Comparison of Line Extraction Algorithms using 2D
Laser Rangefinder for Indoor Mobile Robotics.
...
- 384
2
votes
Is this SLAM performance typical or am I doing something wrong?
Your lidar has a minimum range for 12 cm, which means your maze corridors should probably be double that range (for either side of the sensor), plus the width of the sensor itself, which is 9.5 cm. ...
- 15.9k
2
votes
What wavelengths are most commonly used in laser-scanners and LIDAR systems?
You are correct. Most Velodyne LIDARs (very commonly used on autonomous vehicles), use 905 nm diode lasers, and so do many Hokuyo laser scanners and SICK LIDARs.
A new company, Ouster, uses 850 nm ...
- 1,096
2
votes
What wavelengths are most commonly used in laser-scanners and LIDAR systems?
Both 1550nm and 900nm ranges are used in different lidars.
Velodyne and majority others use 905nm lasers because these diodes are really cheap.
1550nm are used when there is a need for very long ...
- 51
2
votes
Accepted
Likelihood Field Matching
Basically, you are comparing the measurements of your scan with your previously computed map.
You compare all your scans (line 2) for a certain time step that are not range_max (line 3).
You compute ...
- 305
2
votes
ROS Laser Scan rotates with the robot in RVIZ
Behavior like this suggests that your odometry is not being computed properly when the vehicle turns. It's hard to tell but the model appears to have rotated about 90 degrees but the laser scans ...
- 24.5k
2
votes
Res-Scaling method beats PID controller. How?
How is the (P) controller not standing up to its task ?
Well, just like you said - how is it not standing up to its task? What is it doing that makes you think it's not working? You said,
I tried ...
- 15.9k
2
votes
does lidar sensor output data have spatial locality?
For each given sample there is a spacial assumption that you can make. And for each sequential sample there are temporal and spacial assumptions that you can make. These assumptions might change ...
- 24.5k
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