# Questions tagged [mapping]

mapping is the construction of a spatial representation by using the sensory information perceived

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### EKF-SLAM Update step, Kalman Gain becomes singular

I'm using an EKF for SLAM and I'm having some problem with the update step. I'm getting a warning that K is singular, rcond evaluates to ...
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### What algorithm can I use for constructing a map of an explored area using a number of ultrasound sensors?

Ultrasound sensors are incredibly cheap these days which makes them a popular choice for many hobbyist robotic applications, and I'd like to use a bunch of them (say 10) around a robot with an ...
1k views

### The relationship between point cloud maps and graph maps

I am most familiar with SLAM maps that are point clouds, usually in the form of a vector like $<x,y,\theta,f_{1x},f_{1y},...,f_{nx},f_{ny}>$. I also understand how to create a map like this ...
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### In EKF-SLAM, why do we even need odometry when there is a more reliable sensor?Also, are all SLAM algorithms feature-based?

In the book of SLAM for dummies, why do we even need the odometry when the robot would use the data retrieved from the laser scanner which is more accurate than odometry? Why not just rerly on the ...
566 views

### Comparing maps to groundtruth

When you've created a map with a SLAM implementation and you have some groundtruth data, what is the best way to determine the accuracy of that map? My first thought is to use the Euclidean ...
804 views

### How does a robot efficiently store a map it makes?

From what I understand, you can create a map using sensors and storing values in an array. For example, the array can have 0's for places not visited, and 1's for places visited, or 0's for open ...
883 views

### How can I implement tremaux algo in arduino line follower to navigate and create map?

The Map1 The task is divided into 2 runs, In first run, We have to navigate through whole map and reach the end mark taking all checkpoints. In second run, using the mapping from first run we have to ...
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### the uncertainty of initializing new landmark in EKF-SLAM

In EKF-SLAM (based-feature map) once the robot senses a new landmark, it is augmented to state vector. As a result, the size of the state vector and the covariance matrix are expanded. My question is ...
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### A sensor that can see glass/transparent objects and surfaces

I am currently thinking about making a robot that will autonomously drive around the place. The place I want this robot to drive in however contains quite a few glass walls. When mapping the area I ...
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### Navigating through a Maze using path-planning (Dijkstra)

I'm working on an robot that would be able to navigate through a maze, avoid obstacles and identify some of the objects in it. I have a monochromatic bitmap of the maze, that is supposed to be used in ...
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### Matlab: Simulate received signals of sonar sensors [closed]

StackExchange community! I need the guidance what to use for the generation sensor data in Matlab. My purpose is to optimize the exploration process of unknown environment using the multi-robot ...
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### 3D mapping using only a 2D Lidar

How can I map a 3D environment using only a 2D lidar? The lidar would be hand held and it would have 6 DoF. So if I move it in arbitrary motion in all 6DoF, I expect my algorithm to generate a 3D map ...
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### 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 ...
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### EKF SLAM and Mahalanobis distance?

So far I have done EKF Localization (known and unknown correspondences) and EKF SLAM for only known correspondences that are stated in Probabilistic Robotics. Now I moved to EKF SLAM with unknown ...
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### Understanding Drift in Simultaneous Localization and Mapping (SLAM)

I am trying to understand the effect of drift in Simultaneous Localization and Mapping (SLAM). My understanding is that drift occurs because the robot tracks its position relative to a set of ...
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### What is the most appropriate SLAM algorithm for quadrotors with RGB-D camera?

I have been researching on SLAM. I came across EKF SLAM which uses odometry to measure the robot's initial position in the map and as well as landmarks which helps the robot's position to be more ...
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### Mapping formats for small autonomous robots

I have some robot software I'm working on (Java on Android) which needs to store a pre-designed map of a playing field to be able to navigate around. The field's not got any fancy 3d structure, the ...
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### Mahalanobis distance between 2 line features

I am implementing the ATLAS SLAM framework for a ground robot, using EKF Slam for local maps and using line segment features. The line segment features can be abstracted to their respective lines <...
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### Having a hard time understanding this equation in monocular EKF SLAM

Reading this paper on visual odometry, where they have used a bearing vector to parameterize the features. I am having a hard time understanding what the state propagation equation for the bearing ...
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### building a grid map from gps trajectory poses

I am trying to create a feature grid map with Images from camera mounted to the top of the car. Novatel ProPak RTK gps poses Beforehand, I've checked to ensure that the standard deviations of the ...
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### Obstacle avoiding by Pi camera [closed]

I designed a mobile robot with my colleagues for our graduation project, the purpose of it is to detect mines (metals) in a specific area We are programming the robot using Python on Raspberry Pi 3 ...
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### Which is a good and cheap 3D LIDAR or other options? [closed]

Our team is planning to go for European Rover Challenge (ERC) 2018 for which we are designing an Autonomous rover. In order to implement SLAM, we need a way of mapping (with a range of atleast 2-4 ...
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### how to plot $\pm 3 \sigma$ of a landmark in EKF-SLAM

I have implemented 2D-SLAM using EKF. The map is based-feature in which there is only one landmark for the sake of simplicity. I've read some papers regarding this matter. They plot the $\pm3\sigma$ ...
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### Understanding and correct drift when using BreezySLAM (aka tinySLAM / CoreSLAM)

I was looking for a Python implementation of SLAM and stumbled upon BreezySLAM which implements tinySLAM aka CoreSLAM. My robot is equipped with the hokuyo urg-04lx-ug01. I have odometry hence ...
267 views

### Does Monte Carlo Localization need a predefined map?

So I'm doing some reading on Monte Carlo Localization, and it sounds like the approach is based on using a predefined map, but I just need to make sure (because I haven't read anywhere that it ...
1k views

### Is it possible to do SLAM with few IR sensors like Buddy?

I saw Buddy's page and want to purchase for my SLAM research. However, I wonder is it possible to program Buddy for SLAM? According to Buddy's spec, they're only few IR's, sonars and a camera. As I ...
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### Hector SLAM, Matching algorithm

I'm trying to understand the scan-matching part of Hector SLAM (PPT summary). It seems a little difficult to understand, in some cases, how is it possible to actually perform the alignment of the ...
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### Localization within a map with gyro, accelerometer and magnetometer

My goal is to locate precision within a known map. If the size of the map is known, a rectangle 4 x 3 m, and I know the initial position and orientation of the robot, after a certain period of time ...
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### Autonomous Indoor Positioning System Robot based on CV approach

I have some questions regarding an IPS autonomous robot system, Configuration: Mounting a camera to the ceiling of a room Assume the room is a cube of 5mx5mx5m (LxWxH) Assume the camera is ...
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### How to implement the Wavefront algorithm?

I am thinking of creating a robot that can navigate using a map. It is controlled from a PC. An 8-bit controller performs low level tasks and the PC is doing the image processing. I plan to implement ...
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### solving for unknown 2d rotation + translation

This is a continuation of the question I asked here. I thought I'll ask a more concrete question. So far, this is what I have done to transform from a feature point detected by camera sensor in to a ...
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### Why use GraphSLAM?

I am doing some project on Slam. I have a data set of a moving Robot which can give me the value of forward velocity(m/s) and angular velocity(rad/s) and time(s). Now if this data are provided I can ...
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### 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 ...
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### How to evaluate 3D Occupancy grid maps

I would like to know how to go about evaluating 3D occupancy grid maps. I have a SLAM system that produces a 3D OGM (in .bt format using octomap/octovis) I also have a ground truth OGM in same .bt ...
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### How to make a directed graph?

I'm working on an robot that would be able to navigate through a maze, avoid obstacles and identify some of the objects in it. I have a monochromatic bitmap of the maze, that is supposed to be used in ...
103 views

### How to build map for unknown environment? [closed]

In order to create a map for unknown environment, we have two solutions: The size of the area should be given (grid-based maps) so simply we create 2D grid and have our robot to move discrete ...
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### EKF SLAM : Missing older landmarks in new observation

I am a beginner to SLAM and robotics in general and I have been trying to implement SLAM on my GoPiGo3 robot car kit using primarily Chapter 10 from Probabilistic Robotics by Sebastian Thrun as ...
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### Fiducials in conjuction with AMCL

I'm having some trouble getting fiducials (using aruco_detect) to work alongside amcl. The goal here is to use normal amcl localization when a fiducial is not present, and to switch to localization ...
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### Path of the robot

I have built a simple robot which will move from a source to destination. I want to record a 2d path which the robot has taken in real time. Something which is similar to the image I have take.(...
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### 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 ...
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### Self learning maze solving robot using 8bit microcontroller?

I want to know if there is best algorithm and technique to implement self learning maze solving robot in 8 bit limited resource micro-controller? I was looking for some well optimized algorithm and/or ...
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### 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 ...
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### Robot localization without any sensors

Is it possible to localize a robot without any sensors, odometer and servo motors? Assume robot has dc motors and no obstacles.
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### How to use a map created with odometry

I'm using ROS Melodic with Gazebo 9 in an Ubuntu 18.04.2 LTS. I'm studying a robotics subject at the university and I have to create a map of a closed room with one obstacle using only odometry. The ...
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### Help in Computing Inverse Kinematics of a 5 DOF Robot Config

Its is a robot config with 5 DOF. We are provided 2 offsets d1 and d2. d1 and d2 are both 0.04 meter. It is confusing for me alittle bit. I am attending lectures online but I am having trouble ...
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### Pose-graph-slam:using only a camera

I'd like to know how to form my pose graph if the only information I have available is that from a camera, (1) What are my poses? Are they just the accumulated transformations from pairwise matching? ...
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### How to efficiently do 3D mapping of an area on a MAV?

I have been researching on a cost-effective way to scan an area on a MAV (exploraton) and later use it for CAD/civil purposes(use the point cloud data for CAD) but the major sensors available have ...
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### Converting a 2D array of bits to a connectivity map (Code Debugging)

I'm working on an robot that would be able to navigate through a maze, avoid obstacles and identify some of the objects (Boxes in which it has to pot the balls) in it. I have a monochromatic bitmap ...