Questions tagged [localization]
Localization is the problem of estimating a robot's pose relative to a map of its environment.
281
questions
0
votes
2
answers
29
views
Dead reckoning or SLAM for localization with unusual locomotion?
I am working on a senior design project with a robot that moves in an unusual way: it rolls around in a single spherical body, similar to BB-8 from the Star Wars sequels. My personal task for the ...
0
votes
2
answers
39
views
Odometry into EKF for localization
I want to fuse a Lidar-Odometry into my EKF where I'm already using encoder, IMU, GPS. The odometry has as output a delta pose, how to put that into the filter? How to deal with the covariances?
0
votes
3
answers
135
views
Localize a Mobile Robot on a Mirror
I am currently busy with a project which requires me to construct a robot capable of cleaning a heliostat (movable mirror used to redirect sunlight). Heliostats are basically large flat mirrors that ...
0
votes
1
answer
107
views
Localisation of Robot in a Rectangle
I am wondering how to go about localising a robot in a rectangle drawn on a smooth surface. Basically, there is a tape that lines the shape of the rectangle, and the color of this tape is unique in ...
0
votes
1
answer
39
views
How to use a EPM50S8 encoder?
How can I use this encoder with my robot applications?
I couldn't find any tutorial about that and it has a lot of cables. (EPM50S8)
I have read the datasheet but I don't understand the last three ...
0
votes
2
answers
111
views
Collaboration of mobile robot and survaillance camera - classic localization (still) needed?
Just started with the topic of mobile robotics..
so I'm still into concept making and little programming, but have not setup everything or tested at all. I got a (differential) mobile robot (lego ...
0
votes
1
answer
100
views
ROS2 robot_localization not working correctly with namespace
I have a straightforward ROS2 launch script that launches the following:
gazebo client, gazebo server and spawn_entity to spawn a robot in gazebo
robot_state_publisher and map->odom static ...
2
votes
2
answers
138
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 ...
3
votes
2
answers
226
views
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 ...
3
votes
1
answer
77
views
Covariance of Gaussian after sequence of homogeneous transformations
Assume we have a robot that moves and observes landmarks on his path. The path is composed of $k$ poses $s_1 \: ... s_k$ where $s_i = [x,\ y,\ \theta]$. From the sensors, we read the motion ...
0
votes
2
answers
97
views
Robot loses proper localization
Having trouble getting robot to stay localized in map. The lidar maps the correct position of robot but not the odometry or ekf tf. One can see the two positions on graphic below.
The robot base is ...
0
votes
1
answer
78
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 ...
0
votes
1
answer
325
views
odom frame keeps moving in ROS GPS robot_localization
I am using two instances of ROS robot_localization package to get the local and global odometry. In the local one, I am fusing IMU and twist messages. It is working fine. But when I use the second ...
1
vote
1
answer
110
views
Omnidirectional kinematic model in robot_localization's EKF
I am looking for a more detailed mathematical background of robot_localization's kinematic model used for nonlinear kalman filtering.
From the documentation, the ...
0
votes
0
answers
78
views
Extended Kalman Filter Robot Localization Drift
I have implemented an EKF for robot localization in the style of robot_localization using the famous C++ template kalman library....
3
votes
1
answer
189
views
SEIF ,online version of Graph slam create doubt in Motion Update state
I have a thesis work about Graph Slam The GraphSLAM
Algorithm with Applications to Large-Scale Mapping of Urban Structures
I try to implement it with the help of this paper but during the ...
0
votes
0
answers
19
views
Modelling line sensors for localizing a mobile robot using the Kalman Filter
My goal is to localize a mobile robot with Mecanum wheels in a 8m x 10m area, that is outlined with white lines. The robot weighs around 25 kg, and has a top speed of 2 m/s. The localization should be ...
0
votes
0
answers
87
views
multirobot_map_merge package not working properly
I am trying to map a Gazebo environment using 2 husky bots using the multirobot_map_merge package.
However, the merged map being produced is wrong and the robots are not being localized correctly ...
0
votes
0
answers
78
views
How to transform given latitude and longitude data to map frame
I am working with a multi sensor RTK-GNSS for localization of my robot.
This is the data I am getting from the GNSS system.
How to relate this data to my robot map frame for navigation?
1
vote
1
answer
70
views
Self localization for 3 wheeled omnidirectional robot
I am trying to self localize a 3 wheeled omni directional robots using just motor encoders
I followed the odometry method mentioned in equations 5,8,9 of https://bibliotecadigital.ipb.pt/bitstream/...
1
vote
2
answers
114
views
Estimating angular velocity from position
If you have two position estimates $P_{t_1}$ and $P_{t_2}$ and times $t_1$ and $t_2$ how do you extract the average angular velocity from them? The linear velocity is a simple difference but how do ...
1
vote
1
answer
67
views
How to get from lidar coordinates to gps coordinates
I build a map from lidar slam lego-loam, which is a lidar odometer, and then I want to use this map by gps localization.
I know the map will have errors in some ...
1
vote
1
answer
136
views
Fusing non-continuous global pose data
I am fusing the map pose data which is calculated from the fiducial_slam node. Here the topic being fused with ekf_node is /fiducial_pose (geometry_msgs/PoseWithCovarianceStamped). The problem i'm ...
2
votes
0
answers
61
views
Differentiating correspondences in ICP objective function?
The Iterative Closest Point (ICP) algorithm usually alternates between two steps:
Point correspondence finding
Nonlinear least squares optimization of ICP objective function given those ...
2
votes
0
answers
110
views
Kalman Filter for 2d pose
I'm really sorry if this is a dumb question, but I don't have a clue on how to do this. I'm trying to write a kalman filter with a State vector of :
$$
{x,
y,
\dot{x},
\dot{y},
\ddot{x},
\ddot{y}
...
5
votes
0
answers
292
views
Likelihood field sensor model (Probabilistic Robotics, Thrun et al., p.169-174)
I am currently working on the "likelihood field" sensor model (aka "endpoint model") by Thrun et al. (book: Probabilistic Robotics, Thrun et al., p.169-174)
In this context I have ...
1
vote
1
answer
35
views
Lawn Mower Robot Boundary Wire Current
Robot Lawn Mowers have those Boundary Wires where a weak current runs through. This creates a magnetic field around it. The Robot then detects the magnetic field and knows it has reached the end of ...
0
votes
0
answers
52
views
robot_localization ros package: UKF estimate jump but input did not
The UKF is configured to fuse odometry, a reference pose (using ndt matching), and IMU data. But although the robot is standing and all sensors are telling that it is not moving the UKF is jumping see ...
0
votes
1
answer
59
views
Localization by comparing current lidar scan with previous lidar scan
I have managed to use an ICP algorithm to produce a relative pose difference between a new lidar range scan and the previous lidar scan. When I tested it on individual scan pairs, the results look ...
4
votes
1
answer
90
views
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 ...
2
votes
2
answers
630
views
Distance calculation with two robots and two obstacles
I have a problem with two robots and two obstacles in a space. Each robot can communicate its measurements to the other and can measure angles and distances.
The two obstacles in the environment are ...
0
votes
0
answers
24
views
Robot-to-robot relative position over time?
I have 3 robots and I know the starts and end coordinate of each of them. For example for Robot 1 I have Xr1, Yr1 and Xr2,Yr2 coordinates pair , same for Robot2 and 3. I have lateral cameras so can ...
2
votes
1
answer
497
views
How to synchronise data for fusion in Kalman from multiple sensors with different timestamp information?
I'm using Kalman filter to track the position of a vehicle and receive position data from 2 sensors: A GPS sensor and an Ultrasonic sensor for which I want to implement sensor fusion into the Kalman. ...
2
votes
2
answers
454
views
GPS+IMU sensor fusion not based on Kalman Filters
Do you know any papers on or implementations of GPS + IMU sensor fusion for localization that are not based on an EKF (Extended Kalman Filter) or UKF (Unscented Kalman Filter)?
I'm asking is because
...
1
vote
0
answers
433
views
robot_localization not fusing imu data
According to the documentation in : http://docs.ros.org/en/noetic/api/robot_localization/html/state_estimation_nodes.html
I was able to transform the imu data header fram from "imu_link" ...
26
votes
8
answers
18k
views
Absolute positioning without GPS
Using an IMU a robot can estimate its current position relative to its starting position, but this incurs error over time. GPS is especially useful for providing position information not biased by ...
2
votes
2
answers
418
views
Difference between odometry and localization wrt determining robot's pose?
AFAIK, localization is used to determine a robot's pose from a given a map and sensor data. I know of statistical localization approaches which use particle filters to determine a robot's location ...
0
votes
1
answer
29
views
Include information on the environment in map-aware particle filter
I have a robot equipped with some sensors for estimating the movement in a 2D environment (IMU, odometer). The robot is free to move within an area delimited by some walls. The map of the environment (...
0
votes
1
answer
101
views
I'm trying to understand an equation from a motor simulation $\dot w_i (u_ i ,w_i,l _i , \dot l _ i )$
I have a simulated motor and I'm not understanding the math to control it.
This is the equation for the force of the motor, also called an 'actuator'.
$\dot w_i (u_ i ,w_i,l _i , \dot l _ i )$
w ...
1
vote
1
answer
2k
views
robot_localization EKF node does not publish on /odometry/filtered (ROS2 Foxy)
I am using ROS2 Foxy and Gazebo 11 in Ubuntu 20.04. I have a URDF description of a mobile robot that uses 4 wheels for mecanum drive. Using the robot_localization package, I am creating an EKF node ...
2
votes
1
answer
303
views
Why innovation equation in Extended Kalman filter is called innovation?
In the Extended Kalman filter for SLAM, why is the innovation equation called so? Is there a reason for using the specific word "innovation" for the difference between the observed ...
0
votes
2
answers
41
views
Why does the complexity of the particle filter scales exponentially with the number of dimentions?
In the AI for Robotics course from Udacity, Sebastian Thrun mentions that "the complexity of the particle filter grows exponentially with the number of dimensions". Why is this the case? We ...
0
votes
1
answer
98
views
What is the difference between Markov localization and hidden Markov localization?
I just started studying localization for robotics. I started with Markov localization.
There was a cool lecture on Udacity. I also came across another localization called hidden Markov localization, ...
1
vote
1
answer
33
views
Is VIO a good solution for autonomous drone navigation at higher altiutues (200+ms)?
When it comes in indoor scenarios, VIOs may provide good performance, but when it comes to outdoor environments and high altitudes without proper GPS coverage/stability, are current VIOs capable of ...
0
votes
1
answer
422
views
World and Map Frame for a real robot
I am trying to develop a robot for mapping purposes. Currently, I have a Velodyne VLP16 lidar and an IMU. I am having a bit of a confusion in stating the transforms of the system. For the lidar and ...
0
votes
1
answer
360
views
Estimate noise covariance matrix of measurements using a ros-bag
I am facing the following issue, and some hint or orientation would be great. I am working on a project in which I was given a ROS bag, and I have to implement a localization node using SLAM. To do so,...
1
vote
1
answer
112
views
Effect of platform speed (how fast it is moving) on the quality of SLAM
I want to know how big of on an impact does the speed of the platform on which your sensors are mounted have on the quality of the outcome of a SLAM solution. Are there are any methods that are better ...
2
votes
1
answer
91
views
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 ...
0
votes
1
answer
86
views
How to handle curved paths in maze
-I have an RPi on Ubuntu with ROS (Kinetic). The task is to solve a maze. I have implemented a left-hand algorithm to navigate through the maze.
-The robot is equipped with 3 ultrasonic HC-SR04 ...
0
votes
1
answer
128
views
Using Google Cartographer library standalone
I am working on a project that requires the analysis of the results of different SLAM libraries with respect their accuracy on building a map. Right now, I am more interested in the development with ...