Questions tagged [lidar]

Lidar (also written LIDAR, LiDAR or LADAR) is a surveying technology that measures distance by illuminating a target with a laser light. Lidar exists as an acronym of Light Detection And Ranging.

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Why do people use camera instead of laser sensor for robot navigation?

I am working on Robot localization and navigation in urban environments. I want to use a camera. But I am a little bit confused about LRF (laser range finder) data or other laser data. Why people want ...
user14885's user avatar
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10 votes
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In practical terms, how close is the accuracy of camera-based visual odometry/SLAM methods to lidar-based methods for autonomous car navigation?

Benedict Evans, a general partner at Andreessen Horowitz, claims that “almost all autonomy” projects are using lidar for SLAM, and that not all of them use HD maps. An MIT group is testing self-...
T.A. Eady's user avatar
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9 votes
2 answers
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Do multiple LIDAR systems in same area interfere?

LIDARs use a pulse of light to measure distance, usually from the time of flight to reflection and back. With a collection of these measurements they can determine their surroundings in two or three ...
Hrulga's user avatar
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7 answers
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What are some low cost alternatives for lidar? [closed]

It need not be as effective as lidar or it may have some disadvantages when compared with lidar. What are the probable alternatives? Edit: I'm intending to use it outdoors for navigation of ...
seetharaman's user avatar
7 votes
1 answer
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Are there any advantages to using a LIDAR for SLAM vs a standard RGB camera?

I've been thinking about building a small UAV with an onboard LIDAR, just for fun. I'm interested in SLAM and autonomous flight indoors and thought that I would need a lidar to get a 3D map of the ...
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6 votes
1 answer
1k views

LIDAR Points as Landmarks

I am currently trying to implement a GraphSLAM/SAM algorithm for LIDAR. From papers I've read, you generate a directed graph from expected LIDAR measurements to landmarks similar to the image below (...
d.mc2's user avatar
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5 votes
3 answers
6k views

Determining position from a 2D map and LIDAR

We need to determine the 2D position of my robot. To do so, we have a LIDAR at a known high, with an horizontal plane, which gives us the distance to the nearest point for each angular degree (so 360 ...
EngelOfChipolata's user avatar
4 votes
1 answer
161 views

Simple way of 3d perception

I wonder is there any simple (can be computed in microcontroller level) option which is suitable for 3d object perception (depth, position, pose or coordinate estimation) of flying robots except LIDAR,...
acs's user avatar
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4 votes
1 answer
565 views

Likelihood Field Matching

I have LIDAR data of an environment in my hand and I want to apply likelihood field matching to this data. I found a source. But I don't understand what the variables of the algorithm mean and how it ...
umuryasinalper's user avatar
4 votes
1 answer
3k views

ROS Gazebo Odometry Issue

I am setting up a Gazebo model for use with the navigation stack. I have been reading the Navigation Tuning Guide and am confused about the lidar data in the odom frame. I would think that the tuning ...
Connor Fuhrman's user avatar
4 votes
1 answer
3k views

LIDAR solutions [closed]

I am surprised by the price range of Lidar applications considering the simplicity of the design. I try to make a simple project that requires lidar for object recognitions etc. I wouldn't like to use ...
iordanis's user avatar
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3 votes
2 answers
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How come LIDAR is not commonly used for indoor navigation?

I'm reading this survey on the state-of-the-art techniques for indoor positioning and navigation. I noticed that LIDAR isn't mentioned at all in the paper. Is LIDAR not meant to be a common method for ...
John M.'s user avatar
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3 votes
3 answers
2k views

Iterative Closest Point for 2-D LIDAR Data

I have two 2-D point clouds obtained from LIDAR (Light Detection And Ranging) scans at two different poses (positions and orientations) inside a circular structure, where a small object (vertical ...
AEW's user avatar
  • 133
3 votes
2 answers
124 views

How to cope with an optical window limitation on 2D LiDAR?

I have a very small and cheap robot and I wanted to mount a 2D LiDAR on a bottom of it (3cm above the ground). It seems to be great as during the mapping the lidar will detect even small elevations ...
Edmund's user avatar
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3 votes
1 answer
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Waterproofing LiDAR?

I am interested in using a cheap LiDAR module for an outdoor robot I am building. The LiDAR modules that I am looking at are not waterproof and I was wondering how hard it would be to build a ...
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3 votes
2 answers
230 views

How does Lidar penetrate jungle canopy for archeological surveys?

I've read articles like these https://www.nationalgeographic.com/history/article/maya-laser-lidar-guatemala-pacunam and wanted to understand what's going on here. My understanding is the lidar would ...
blueether's user avatar
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3 votes
1 answer
1k views

ROS Laser Scan rotates with the robot in RVIZ

I am currently working on developing a ROS application for autonomous navigation using AMCl. I am first trying to get move_base to work before continuing with AMCL. ...
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3 votes
2 answers
380 views

Lidar problems in a multi-robot setup

Consider multiple mobile bases driving around in some area. In order to get meaningful data from the lidar of each base, the sensors should be mounted as horizontal as possible. Due to safety ...
Mehdi's user avatar
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3 votes
1 answer
104 views

Assistance in finding correct LIDAR for short-range object detection task [closed]

I am working on a task that involves finding a distance of a moving object going a static linear object, e.g a long pole. After trying some approaches (mostly involving stereo vision), I have come up ...
xen20's user avatar
  • 31
3 votes
2 answers
3k views

How to get unix/posix time stamp in header of ROS msg?

I am using two sensors each connected to different machine (each machine separately runs Ubuntu 16.04 and ROS Kinetic). When I echo topic on these two machines, I ...
fhm's user avatar
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3 votes
2 answers
332 views

Cannot see ground plane patterns with LiDAR

I mounted VLP-16 on the roof of my car while driving, I was expecting the lidar to detect the lanes on the ground since the white lines should have higher reflectivity. But in fact I cannot see any ...
PWCTW's user avatar
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3 votes
2 answers
2k views

How to move a robot to a point while avoiding obstacles?

I am trying to move a robot in a straight line from point A, to point B. The robot's primary sensor is a Hokuyo URG-04LX-UG01 LIDAR that gives me the magnitude and direction of each point it detects ...
oodan123's user avatar
  • 131
3 votes
1 answer
86 views

What different sensing approaches are used in the current batch of indoor 3D cameras?

I'm aware of the PrimeSense camera powering the Kinect. Are more advanced sensor types available now in the < $500 range? For example, has there been any sort of game-changer in structured light ...
James Jolly's user avatar
3 votes
0 answers
197 views

Sensor model and Inverse sensor model using occupancy grid mapping with lidar for particle filter

I'm a bit confused about how one goes about calculating the sensor model $p(z_t|x_t, m) $ and inverse sensor model for position $p(x_t |z_t,m_{t-1})$. From this answer, it seems like one way for ...
oswinso's user avatar
  • 141
2 votes
2 answers
77 views

Extract laser scan from a map and known location

If we have the map of an environment (an occupancy grid for instance) and precisely know the pose of the robot within it. How can one reconstruct what the laser scan should look like at a given ...
rob_newbie's user avatar
2 votes
2 answers
305 views

Multiple Line Estimation

Background: I am working on a design in which an autonomous RC car implements a LIDAR sensor to navigate a course. The primary LIDAR sensor returns a 270 array of points, scanning in a line like ...
Michael Choi's user avatar
2 votes
2 answers
335 views

What kind of lidar is necessary for SLAM?

I've read about various robots using a 2D lidar system for SLAM ( such as at IGCV, http://www.igvc.org/ ) but I'm wondering how good exactly does the sensor have to be? Specifically: What accuracy ...
Rydbergite's user avatar
2 votes
1 answer
112 views

Webots: Spawn multiple nodes and disable collision between them, but not the environment

In Webots, I am spawning 10 vehicle nodes at the same time and position for reinforcement learning. I would like the vehicles to not interact with each other (collision and LIDAR) but still have ...
Computing Corn's user avatar
2 votes
1 answer
644 views

Merging multiple LIDARs real time

Is there a standard practice for merging the pointclouds generated by several LIDARs when there is overlap? For example, if my vehicle has two LIDARS (front and back) I'd rather fuse and deal with a ...
Morten Nissov's user avatar
2 votes
1 answer
761 views

Is this SLAM performance typical or am I doing something wrong?

I'm experimenting with SLAM for the first time. I am using ROS on a Turtlebot3, which has a Raspberry Pi and a single Lidar sensor, Robotis LDS-01. I am running a configuration with three computers, ...
pitosalas's user avatar
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2 votes
1 answer
3k views

Calculating acceleration and velocity

I'm writing some Quad Copter software and beginning to implement an altitude hold mode. To enable me to do this I need to get an accurate reading for vertical velocity. I plan to use a Kalman filter ...
Joseph Roberts's user avatar
2 votes
1 answer
139 views

How to perform map matching algo using lidar scan s

I have run a code to extract features from lidar scans like poles and facades, and I created the reference map just concatenating results from each scan (i.e local map) now my question is; How can I ...
ANAS.C's user avatar
  • 123
2 votes
1 answer
93 views

What is the state-of-the-art approach to detect moving objects from mobile robot with 2D Lidar only?

Having a setup of a mobile robot with a 360° 2D lidar (1 plane). What is the current easiest approach to detect moving object with a high reliability from a moving robot? To make it simple, we ...
ywiyogo's user avatar
  • 141
2 votes
2 answers
169 views

LiDAR Feature Extraction

I'd like to extract "features" of an environment scanned with a 2D LiDAR. I tried to create a temporary occupancy map to extract "corners" with the Harris Corner Detector. However ...
user740171's user avatar
2 votes
1 answer
310 views

Applying Rotation & Translation Matrix Obtained from Iterative Closest Point

Suppose I have M lidar contour points from t = k and N lidar contour points from t = k+1. (Some of you might question why I have differing number of contour points, and the reason is that these lidar ...
Dong Jae Lee's user avatar
2 votes
1 answer
512 views

Fusing Multiple Lidars Into 1 Point Cloud

I have a car with 8 lidars, each with a field of view of 60 degrees. My car looks like this How can I merge all the lidar readings into 1 point cloud?
Josh Goldman's user avatar
2 votes
1 answer
939 views

How to determine the rotation matrix and translation vector of a fixed LiDAR from the sensor frame to an aircraft's vehicle frame?

I am using a fixed 3D LiDAR sensor on a small aircraft. The vehicle has a GPS/INU to calculate its own position and orientation. I do not know the exact offset of the LIDAR from the center of the ...
Infinite Learning Loop's user avatar
2 votes
1 answer
677 views

Regarding Pose Graph Slam using Lidar

So I'm trying to incorporate pose graph optimization into a mapping framework using a Lidar. So I basically have all the relative transformations between the pointclouds and I have pairs of ...
arunabh sharma's user avatar
2 votes
1 answer
2k views

Inexpensive lidar/radar rangefinder good up to 100m? [closed]

I've been looking around for a lidar/radar rangefinder for a few months now and can't seem to find anything reasonable for my application. My requirements are pretty straightforward: 100m range I2C ...
DrTarr's user avatar
  • 153
2 votes
1 answer
146 views

Directly observing lidar laser rays

I am working with SICK lidars and have to mount/unmount them quite often on my robot. The mounting process is very tedious especially when it comes to making sure that the lidars are horizontal. I ...
Mehdi's user avatar
  • 681
2 votes
3 answers
517 views

What are the approaches for indoor robot positioning? [closed]

I understand that most of the self-driving cars solutions are based on Lidar and video SLAM. But what about robots reserved for indoor usage? Like robot vacuums and industrial AGVs? I see that Lidar ...
teddy teddy's user avatar
2 votes
0 answers
20 views

Is there any LIDAR 3D perception package for ROS2?

I spent a very long time searching GitHub, Google, and many other sites, looking for a LiDAR recognition package for ROS2, but I could only find one nvidia pointpillar model. Because it requires a lot ...
user192301's user avatar
2 votes
0 answers
264 views

Applying initial guessing to LiDAR point cloud for ICP processing in Graph SLAM

I am currently in the process of implementing Graph SLAM using ICP and g2o in python 2.7 The data I have are pose data (4 x 4 transformation matrix) and lidar data ( in the format of [x y z 1] with ...
David Lee's user avatar
2 votes
1 answer
294 views

Will Lidar see a fence?

I am looking at the possibility of using LIDAR to do obstacle avoidance for a robotics project I am working on but the project involves avoiding a chain link fence. Has anyone used LIDAR to detect ...
user avatar
2 votes
1 answer
151 views

What sensors can track small objects (5 cm - 25 cm) in bright sunlight? [closed]

ToF (time-of-flight) cameras seem susceptible to bright outdoor conditions. Are there any sensors made for bright outdoor conditions and could be embeddable in a robot that could detect and/or track ...
Crashalot's user avatar
  • 161
2 votes
1 answer
1k views

Landmark extraction algorithm

The landmarks are often used in SLAM. What are the algorithms used to extract them, and how can a robot differentiate the landmarks, if they detect one in point A at Xt and another in Xt+1? How can ...
namster's user avatar
  • 23
2 votes
1 answer
49 views

Appropriate distance sensing technology for specified conditions [closed]

I have been considering different distance sensing technologies for the following circumstance: Range needs to be about 2.5 meters The surface being measured is a wall that is painted black The ...
Murey Tasroc's user avatar
1 vote
3 answers
9k views

What is the definition of the contents of PointCloud2?

What does the contents of PointCloud2 means in ROS? fields.offset? fields.datatype? ...
Benyamin Jafari's user avatar
1 vote
2 answers
649 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
  • 133
1 vote
2 answers
82 views

does lidar sensor output data have spatial locality?

i have a question about the output of lidar sendor (like velodyne vlp-16, etc) Is there any spatial or temporal locality for output data which is from lidar sensor? Does the produced output data from ...
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