Skip to main content

Questions tagged [laser]

LASER (Light Amplification by Stimulated Emission of Radiation) is an optical device, which emits monochromatic, directional, and coherent light beam (laser light). Commonly used in distance measuring devices such as LIDAR.

Filter by
Sorted by
Tagged with
0 votes
0 answers
22 views

SLAM TOOLBOX: Moving Interactive markers chrashes the node

I am using the SLAM toolbox with O. I serialized a map that contains a big area; the map is about 7391 x 14586 mapped with a resolution of about 0.05. This size is because I started the mapping ...
Sunart24's user avatar
0 votes
1 answer
97 views

Could not get base to fixed frame transform, Lookup would require extrapolation into the future

I'm trying to figure out what is causing this message. I am using an rplidar, and launching like so: roslaunch rplidar_ros rplidar.launch Then I create a transform ...
jgauthier's user avatar
  • 151
1 vote
1 answer
108 views

Dispersion of object edges in lidar point cloud

I'm having an issue with some spurious points appearing in the point clouds coming from my 3D lidar. More specifically, I'm working with an RS-Bpearl lidar, and the point clouds that I receive from it ...
Constantin's user avatar
0 votes
0 answers
60 views

3D LiDAR Data Inconsistency and Costmap Performance Optimization

I hope this message finds you well. I am currently engaged in a project utilizing a non-repetitive 3D LiDAR system, characterized by a Vertical Field of View (VFOV) of 52° to -7° and a Horizontal ...
Sunart24's user avatar
0 votes
4 answers
296 views

Lidar/laser scan moves when the bot is moving while generating map

I have been trying to generate a map using lidar/laser scan data in my 4_wheel_bot with the help of slam_gmapping package. When i start the simulation the output of the terminal shows "...
Vasanth's user avatar
  • 17
0 votes
0 answers
43 views

How can I derive a metric comparing two 2D laser scans quantitatively, WITHOUT using any scan matching techniques?

TLDR version: I have two laser scans taken at the same pose that align nearly completely (see image). I want to come up with a metric that can quantify how well one did as opposed to the other. Longer ...
Shrinivas Iyengar's user avatar
0 votes
1 answer
260 views

Why does the laser cut through walls? ray_plugin

I have build a robot with a urdf to visualize in gazebo. After some struggle being new to gazebo I got it working. I then decided to make a video series for myself and others on how I did it. Sadly ...
TK noob's user avatar
0 votes
1 answer
141 views

How do I implement accurate distance measuring to ground on a rover?

I need the end effector to always be at a fixed distance from the ground, I need that the end effector is as close as possible to the ground, the closer the better. Given this proximity I need to know ...
Invokeseth's user avatar
0 votes
1 answer
113 views

Nav2 makes obstacles where there are none

I'm using Jammy and Humble and Nav2. The robot is beginning to do waypoint following and driving on his own. However, sometimes the Nav2 program is making black dots, as obstacles, appear where there ...
Russ76's user avatar
  • 54
0 votes
0 answers
29 views

Object racking on conveyor belt using low cost Lidar or similar non-camera options

The requirement is that movement of products right from the start to end of the conveyor belt (of length around 2.5 m) need to be tracked. The same can be easily done using any IP Camera and OpenCV ...
NEEK's user avatar
  • 1
0 votes
3 answers
3k views

Lookup would require extrapolation into the future on the same machine

I get this error when trying to view my RPLidar A2 scan in rviz2. It’s on a differential drive robot controlled using arduino using Articulated Robotics’ code that I quickly ported to Humble, ...
Redstone's user avatar
0 votes
1 answer
11 views

Costmap doesn't consider laser beams behind the robot (only when the laser frame is flipped upside down)

Hello everyone, I'm currently implementing the navstack on my robot and I have a problem with the generation of my costmaps : I use the obstacle layer plugin to make dynamic obstacles from the LiDAR ...
user avatar
0 votes
1 answer
22 views

Lidar - What is the difference between the /scan and PointCloud?

I watched a tutorial for converting laser scan data to point cloud. But I could not understand how this conversion works. What is the difference between the scan and point-cloud data and what are ...
user avatar
1 vote
1 answer
294 views

Is there regulation of LiDAR in the public space?

Are there any regulations (in the US or the EU), plans to regulate or initiatives that think about the "pollution" with or amounts of laser emission in urban spaces in general and the impact ...
Micropolis's user avatar
0 votes
1 answer
10 views

How to visualize the laser scan data as a local/global map?

Hi, my robot in ros melodic has a lidar and I want to visualize the laser scan data. Previously I used the local_costmap, but since it became more complicated and now it consists not only of the laser ...
user avatar
0 votes
2 answers
97 views

Laser Scanner Rotation when the robot is moving

Hello there everyone, I am running into an issue with the navigation stack with move base and AMCL in ROS. The issue is, every time the robot rotates by a certain degree, the laser also rotates and ...
user avatar
0 votes
2 answers
564 views

What robotic simulators simulate the reflectivity of objects?

I want to simulate the reflectivity of objects in a simulation because I want to use a 2D laser scanner to detect certain objects that have higher reflectivity than other objects in a particular scene....
andrestoga's user avatar
0 votes
1 answer
26 views

Mapping by gmapping isn't correct

Hi, I'm doing the mapping process by gmapping. At the beginning, my robot can recognize a wall very well, but when i spin the robot and face into empty space, it suddenly appears a line on the map in ...
user avatar
0 votes
1 answer
18 views

Using multiple laser scans for gmapping

Hi, I'm trying to do the SLAM mapping with gmapping on my robot, which has 2 lasers on it, in the font and in the back of the robot. So how can I use 2 laser scans for gmapping, since gmapping only ...
user avatar
2 votes
1 answer
227 views

How to detect loop closures in 2D laser SLAM?

I am trying to build an occupancy grid map using odometry and 2D lidar data through graph optimization. I am not aware of any reliable loop closing methods using only the 2D laser scans. I have been ...
anonymous's user avatar
  • 121
0 votes
1 answer
107 views

Converting x, y, z array to point cloud data

Hello ROS developers, I am trying to convert a2D array to a point cloud value and publish it thereby visualising it in rviz. Can anyone guide me to solve the below issue which I am facing during the ...
user avatar
0 votes
1 answer
45 views

Trouble aligning/calibrating camera with laser scanner

I have a robot which has 2 multi-spectral cameras and 1 laser scanner attached. In the end I would like to have the images from the cameras aligned with the scanner so that I can have spectral ...
Steve Ahlswede's user avatar
0 votes
1 answer
45 views

Who publishes the map frame?

ROS Melodic, Ubuntu18, Gazebo9 Issue: Not able to visualize laser scan data in rviz Error: No tf data. Actual error: Fixed Frame [map] does not exist Steps to recreate: Launch gazebo with ros ...
user avatar
0 votes
1 answer
82 views

How to get ira_laser_tools laserscan_multi_merger to subscribe to laser scans?

I'm using the laserscan_multi_merger node from the ira_laser_tools package to combine 2 laser scans. I have demonstrated this ...
user avatar
0 votes
1 answer
106 views

Call clear costmap service periodically

Hello. I have the ROS navigation package on Kinetic with a Realsense camera. I am transforming the depth image of the camera to laser scan, and then with that laser scan generate obstacles with the ...
user avatar
0 votes
3 answers
313 views

Clear obstacles of obstacle layer of costmap

Hello everyone. I have a Realsense D435 camera on my application, and I use its depth_image to generate a laser scan topic with the package depthimage_to_laserscan. This works allright. The problem I ...
user avatar
0 votes
2 answers
8 views

Laser scan topic returns many messages

I am using a very simple subscription to a /scan topic to get the laser distances that my hokuyo laser scanner has grabbed, using: ...
user avatar
0 votes
1 answer
17 views

No SICK TiM devices connected! sick_tim320?

i use melodic, i try to connect sick tim_320 but i have some problem [ERROR] [1578729117.004873938]: No SICK TiM devices connected! [FATAL] [1578729117.004962667]: Failed to init device: 1 [ERROR] [...
user avatar
0 votes
1 answer
5 views

laser_scan_matcher building problem

Basically I'm trying to get laser scanner data in world coordinates. I would like to make it possible to get the whole point cloud data with subscriber node from python code to work on it (I'm making ...
user avatar
0 votes
3 answers
422 views

Understanding the SICK S300 RS422 data output

I'm using a SICK S300 safety scanner connected via RS422 -> USB and I'm trying to decode the lines of data into meaningful values, however looking at the data compared to the Telegram Listing it seems ...
fzeta's user avatar
  • 1
0 votes
1 answer
384 views

Error: For frame [Laser]: Frame does not exist

Hi!, I am trying to build a map using roslaunch turtlebot3_slam turtlebot3_slam.launch slam_methods:=gmapping on a turtlebot3. Unfortunately I have issues with the ...
user avatar
0 votes
1 answer
31 views

Using multiple RPlidar on a single system

Hello, i would like to use two (or more) rplidars at the same time. When i start the second RPLIDARnode, the first one closes. I tried to find a connection to rosserial, but it seems rplidarnode ...
user avatar
0 votes
1 answer
16 views

Hector Mapping PointCloud2 Map

Good day everyone. I am using Ubuntu 18.04 with RO Melodic. Currently i am using hector mapping to obtain a map and view it in RVIZ. It subscribed to laser scan type topic and published an ...
user avatar
0 votes
1 answer
2 views

Reading data from the shifted laser, as if it was in the middle

I have algorithms that use raw data from laser [-pi/2;pi/2]. Earlier, the laser was in the middle of the robot. Now it has been moved closer to the left front edge and rotated by pi/4. What is the ...
user avatar
2 votes
2 answers
692 views

What wavelengths are most commonly used in laser-scanners and LIDAR systems?

In Photography SE I've just asked LIDAR burnout; ways to check for damaging infrared lasers before shooting besides looking for posted warnings? and discussed a camera that was damaged by a self-...
uhoh's user avatar
  • 145
0 votes
2 answers
15 views

Gazebo Hokuyo laser not working properly

Hi all, I´m trying to run some mapping experiments with a mobile robot on a Ubuntu 16.04 machine with ROS Kinetic and Gazebo 7. What I did was to define a diff-drive with the following urdf: https://...
user avatar
0 votes
1 answer
37 views

How can I modify the Laser angle scan?

I have an RPLidar and from its documentation, the laser can do 360 degrees. The thing is, I do not need full 360 degrees as some area will constantly block the laser sensors. So basically, I only need ...
user avatar
0 votes
1 answer
26 views

No laser scan received

Hello, I know this question has been asked many times for single robot but i cannot figure it out for my multi-robot-system. Please Note: It is perfectly working for a single robot. But it is giving ...
user avatar
0 votes
1 answer
7 views

UTM-30LX not detected on /dev/ttyACM(*) by Ubuntu

I am trying to connect my UTM-30LX to ubuntu 16.04 running ROS kinetic using the urg_node. I have installed URG and I am following this tutorial http://wiki.ros.org/hokuyo_node/Tutorials/...
user avatar
0 votes
1 answer
22 views

Create Restrict Area on /Map

Hello, I want to create restriction area for path planning. Robot mustn't go restriction area that user's indicated. In additional map mustn't include obstacle that not sensor's seems. Is it possible ?...
user avatar
0 votes
1 answer
181 views

Object detection using ToF sensor

I am making an indoor robot and in order to detect static and dynamic objects I have decided to go with ST VL53L1X ToF proximity sensor, here is the link: https://www.st.com/en/imaging-and-photonics-...
Edmund's user avatar
  • 153
0 votes
1 answer
1 view

The source of topics in someone else's package

I'm going through this package, and in particular this file in which I found three topics whose "source packages" and meaning are unknown to me: ...
user avatar
0 votes
1 answer
12 views

Configuring turtlebot3_slam_gmapping

Is there a way to unsubscribing the turtlebot3_slam_gmapping node from the topic /scan and in place of that, subscribing turtlebot3_slamp_gmapping to a topic published by /scan_to_scan_filter_chain ? ...
user avatar
0 votes
1 answer
35 views

Convert pointcloud 3d point to image pixel

Hello there. I have a rosbag that contains a camera footage topic (sensor_msgs/Image) of a room and a laserscan topic of the same room. I also have a program that converts this laserscan to a ...
user avatar
0 votes
2 answers
28 views

Minimum distance from laser scanner data

I have been trying to get the minimum distance from laser scan data. My code is as follows: Here, "msg" is the "const sensor_msgs::LaserScan::ConstPtr &msg" from the callback. ...
user avatar
0 votes
1 answer
2 views

Actuators used with 2d laser scanners to produce 3D images on ROS

Hi, The acquisition of 3D LIDAR is mainly based on the rotation of the 2D laser scanner around a certain axis. I mean a standard 2D laser scanner and mechanical rotational element are required for 3D ...
user avatar
0 votes
1 answer
2 views

sharp ir sensor

i add 8 sharp ir into my robot, how to see in my rviz, and how to add tf for ir laser. my main laser is hokuyo ust 10lx. help me please. thank you Originally posted by zucky on ROS Answers with karma:...
user avatar
0 votes
1 answer
3 views

laser scan topic

i install ros indigo desktop full and Turtlebot2 Ubuntu Package . when i do $rostopic list i cant find /laser/scan topic . there'...
user avatar
0 votes
1 answer
9 views

Invert rviz scan screen 180 degrees

Hi, I reversed a 2d laser scanner that rotated 360 degrees through a servo motor. Because I turn it backwards, there is a reverse image on the Rviz platform. that is, the ceiling looks like a base, ...
user avatar
0 votes
1 answer
13 views

Publish LaserScan from Arduino

Hello, I am using an arduino Mega to publish LaserScan message. But I have a weird result, when i run this code: ...
user avatar

1
2 3 4 5 6