Questions tagged [slam]

SLAM (Simultaneous Localization And Mapping) refers to a robot building a map of its environment through it's sensor data (mapping) and keeping track of its own position in that map (localization) at the same time.

Filter by
Sorted by
Tagged with
0
votes
1answer
31 views

Does every rotation vector has an one-to-one corresponding rotation matrix?

Given a rotation vector, can we always get the same corresponding rotation matrix computed by the Rodrigue's rotation formula?
0
votes
1answer
16 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 ...
0
votes
0answers
14 views

Can someone share with me some modern review paper about the filter-based SLAM?

I'm currently learning the Visual SLAM. But I'm also very curious about the modern filter-based SLAM. Can someone share with me some modern review papers about it?
1
vote
0answers
29 views

How is the depth estimation done in DTAM / LSD-SLAM (direct VSLAM)?

I know that DTAM and LSD-SLAM both employ the photometric error between two keyframes to estimate the image depth. But I don't know what the photometric error describes precisely. In the DTAM paper, I ...
2
votes
0answers
22 views

How do you handle angle discontinuities in estimation problems?

When one is implementing a state estimator in a system that involves kinematics, will inevitably face the problem of angle discontinuities, i.e., the fact that the angles have to be wrapped between ...
1
vote
3answers
31 views

Occupancy grid maps

Why do we take probabilistic approch to model the environment for robots in occupancy grid maps.The assumption is always taken that each cell on the grid map is either free or occupied.So why have ...
0
votes
1answer
22 views

ICP(Iterative Closest Point) with Partially Overlapping Conditions & Changing Point Numbers

I am currently working on fixing vehicle odometry data using lidar contour points. Since I am receiving lidar data in the form of countour points, I thought I'd use ICP to correct the odometry error ...
0
votes
1answer
16 views

Vehicle Odometry Correction Using Lidar Contour Points (Localization)

I am currently working on a project where... Vehicle travels from point A to B GPS trajectory is used as a reference Vehicle odometry (bicycle model without slip angle beta) was used to estimate a ...
2
votes
2answers
48 views

Compute path in absolute frame from sequence of measurements

I have a sequence of measurements $\{(x_i, y_i, \theta_i)\}_{i = 1 \:...\: N}$. Each of these represents the new pose of the robot seen from the previous pose, i.e. a measurement $(x', y', \theta')$ ...
0
votes
0answers
18 views

Motion model and homogeneous transformation issue on a drone

I am trying to develop a EKF-SLAM algorithm for a drone, and I want to estimate its position in the inertial/world reference frame. I have as control variables the linear and angular velocities in the ...
0
votes
0answers
18 views

Are there some papers or books that compactly elaborate the essential part of the multiple view geometry?

I am a novice to visual SLAM and computer vision. Recently I've read a paper "A micro Lie theory for state estimation in robotics" dedicated to introducing the essential part that necessary to ...
0
votes
0answers
23 views

Robot Localization - Motion and Sense Probability

I'm currently taking Udacity's AI for robotics course and came across a question that stumped me. The problem plays on localization probability given uncertainty in our measurement updates. The first ...
1
vote
0answers
19 views

Caculate/Specify the covariance matrix for a omniwheel robot

I have an omnidirectional robot (x, y and rotation around z), which I would like to use the SLAM-algorithm from ROS. But the odometry from the robot has a drift, which makes some error. To improve the ...
0
votes
0answers
15 views

Bundle Adjustment for Monocular SLAM

I am confused with how monocular BA works in visual-based SLAM. Is there any tutorials I can do in openCV to provide me some visualization aid? Thank You.
0
votes
1answer
34 views

EKF-SLAM what should the observation model be?

I am implementing an EKF algorithm for a drone localization, and while I was defining the observation model I got a bit confused. This is my situation: I have a drone which is able to give me the ...
0
votes
1answer
27 views

What is the concepts of submaps in LIDAR based graph slam algorithms?

I have been reading some slam papers recently and many of the papers mention building and performing scan matching on submaps instead of individual poses. Does it mean that a submap is just a single ...
0
votes
2answers
56 views

Which math books would help in learning SLAM systems? [closed]

Recently I started studying papers on SLAM systems by Durrant-Whyte for my research and I'm finding some difficulties in the math (matrices and probability) that is tackled in these papers. Which ...
0
votes
2answers
45 views

Guidance on SBC for Visual-Based SLAM [closed]

Intro: I am a student that just started a project regarding prototyping a mobile robot that involve Indoor SLAM implementation. I am very new to the field of computer vision, SLAM and SBC (single ...
2
votes
0answers
41 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 ...
0
votes
0answers
17 views

How does a recursive Bayesian depth filter is used to build a map in visual odometry?

I am trying to understand a paper on visual odometry and I am having troubles understanding how a map is generated using a stereo camera as sensor. The paper I am reading is SVO: Semi-Direct Visual ...
0
votes
1answer
28 views

On the covariance matrix of the EKF SLAM

In the covariance matrix of the EKF SLAM, there are components that specifies the correlation between landmarks. Are those values important? Because while we bulding map of landmarks, we only draw the ...
1
vote
1answer
40 views

Dual constraint non-linear optimization for SLAM

I am trying to achieve a nonlinear optimization for SLAM on a function that contains two different constraints, like this : $$ T_{opt} = \underset{T}{\arg\min} \sum_i(\left\lVert T.X_i - x_i \right\...
0
votes
1answer
34 views

Good Software Projects for Aspiring Engineers [closed]

With the pandemic going on, our school has decided to officially shutdown all sponsored club meetings. Now that we are all digital, our robotics club was looking for projects that students can do at ...
0
votes
3answers
98 views

Difference between SLAM and Localization

What are the differences between SLAM and Localization if you have a known map? How does the position probability update differ between the two? In particular I'm curious on if localization is a ...
0
votes
0answers
31 views

What are the limitations of RatSLAM?

I recently read about RatSLAM, a visual SLAM implementation that only needs a simple monocular webcam to map and localize, instead of the usual high precision range finders and encoders that most SLAM ...
0
votes
0answers
11 views

Object Avoidance Using Intel Realsense

Are there any open source projects that use intel realsense for object avoidance and navigating to a destination?
1
vote
0answers
28 views

Intel Realsense Cameras for Object Avoidance and SLAM to go to destination

My goal is to make a UAV which can search an area while avoiding obstacles. I figured I would navigate using the SLAM and Intel Realsense D435i (a stereoscopic camera with an IMU built in), but all of ...
0
votes
1answer
29 views

Uncertainty in grid based fastslam

Given I am building a grid map, and poses are represented using particles, how can I calculate the uncertainty of a pose In a grid based fastslam 2.0?
0
votes
0answers
8 views

loop closing in grid based fastslam 2.0

I understand how grid based fastslam 2.0 works I just would like to know how to implement a loop closure functionality in a grid-based fastslam 2.0? Since at each state we only consider the last state ...
2
votes
2answers
56 views

What Software Is Used For Autonomy Software Simulation?

I don't have a physical robot but I would like to test the performance of my C++ code for odometry, SLAM, and path planning. Are there any good simulation software where I can test my algorithm ...
1
vote
1answer
28 views

How to derive the camera trajectory from ICP

This may be a very simple question so please bear with me... Suppose I have a stationary object and point clouds, $n$ $(x,y,z)$ points, of that object taken by a moving camera at time steps $t_i$, $...
0
votes
0answers
32 views

Rescaling a local Map in VSLAM (orb slam)

I am trying to inject metric scale into a vslam algorithm, namely the popular ORB-SLAM2. I have read several papers(1,2) whereby people have successfully calculated scale factor from the actual height ...
1
vote
2answers
28 views

Can standard SLAM techniques be used in maritime environments, where waves and currents move the vessel even with no control input

I am trying to implement a functioning SLAM system for an autonomous surface vessel (ASV). I don't have any direct experience with SLAM, and I am therefore researching the topic before I try to ...
0
votes
1answer
33 views

Hector_Slam orientation probelm for drone

We are using Hector slam(2-D Mapping) for our drone in which we are facing some problems 1) as the orientation(axis) of the lidar changes the orientation of map changes 2) as the plane of the lidar ...
0
votes
0answers
24 views

Ceiling Camera & robot - SLAM still neded?

I've got a question regarding the topic of SLAM. My composition consists of a mobile robot and a top down looking 2D camera with wide-angle lens. It is comparable to a survaillance camera mounted on ...
3
votes
3answers
69 views

Is SLAM done only first time in a given environment

I am training Turtlebot 2 to move around the office. I come from robotics hardware background but relatively new to computer vision and robotic mapping. Here are my two fundamental questions related ...
1
vote
1answer
38 views

How does scan matching find overlapping regions in two scans?

I have been reading about scan matching and so far I have gathered that scan matching tries to find the transformation (rotation and translation) which leads to the best match between overlapping ...
0
votes
0answers
29 views

Google Cartographer: bag validation detects gaps in LIDAR messages

I'm using google cartographer to do SLAM, and I'm experiencing some accuracy issues, in particular my map rotates and gets distorted when the robot rotates. I run ...
2
votes
1answer
48 views

Make robot drive as far from obstacles as possible

I am trying to make robot drive around the room, avoiding obstacles with pathfinding. The problem is I get few waypoints from pathfinding algorithm for robot to drive to (green dots), but it drive a ...
2
votes
2answers
50 views

How to handle landmarks in Bundle Adjustment?

At the moment I try to understand Bundle Adjustment on a level to be able to implement it on my own. The major point I'm still confused at is the management of the landmarks. So, let's think of a few ...
2
votes
2answers
50 views

What's the difference between Pose Measurement and Position Measurement?

I have read a robotic related paper called Estimating SE(3) elements using a dual quaternion based linear Kalman filter, and the author proposed that the equation of position measurement is denoted as:...
0
votes
0answers
25 views

How to obtain live vertical height values using LIDAR

I plan to control the flying height of my drone using a LIDAR (in real-time). Therefore, I would be attaching the LIDAR to my UAV, pointing vertically downwards. However, after looking at some of the ...
0
votes
1answer
33 views

Feasibility of SLAM with heterogeneous sensors

Why are there so few published implementations of SLAM with support for heterogeneous sensors? Heterogeneous sensors include LIDAR, monocular cameras, stereo cameras, thermal sensors from more than ...
0
votes
0answers
37 views

Are there any Algorithms/Papers about 3D Mapping the Interior of Buildings using Computer Vision and IMU Data?

I was wondering if it would be possible to do something like this: Vision-based Autonomous Navigation and Mapping with a Small Quadrotor without using lidar/lasers. I have tried ORB-SLAM, but the ...
0
votes
1answer
50 views

Usage of Falkolib(OpenSLAM) for 2D lidar landmark extraction

I am using Falkolib for landmark extraction in a 2D environment. Currently I am using the testKeypointOC executable from the bin directory. I have changed the testKeypointOC.cpp file and the ...
0
votes
0answers
22 views

Robot localization including the orientation of the boundary

Consider a SLAM system for a mobile robot that is able not only to predict the position wrt the map boundary but also to measure the orientation of the boundary once it is reached. If the measured ...
0
votes
0answers
17 views

Integrating Arduino Cloud Platform into ROS

I have an existing ROS framework used for an autonomous driving vehicle. I am working on tests to understand how localization is affected by light. My existing hardware does not have a lux measurement ...
0
votes
0answers
21 views

What is the difference between SLAM and cooperative localization?

I need to ask this simple question for my own understanding. I am new to the field and want to differentiate between the two.
0
votes
1answer
46 views

Teaching AMCL and SLAM

In trying to explain these important concepts and algorithms it would be super useful to have a video or animation that illustrates through simulation the underlying math. All the videos and articles ...
0
votes
0answers
31 views

IMU + odometer SLAM techniques without vision and depth

Consider a mobile robot provided with a contact sensor that randomly travels in a closed environment, changing direction every time an obstacle is encountered. Is it possible to reconstruct the 2D map ...

1
2 3 4 5 6