Questions tagged [ekf]
the extended Kalman filter, a filter for nonlinear state estimation.
256
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Robot Localization pkg / Motion Model prediction step
As I was investigating the transition functions in the prediction step in the ROS Robot Localization pkg (ekf.cpp) .
I found for the orientation equations there are as follows:
Roll angle is the ...
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1
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Frequency Limitation in robot_localization's EKF Node
I'm using version 2.7.4 of the robot_localization package for ROS Noetic.
I'm currently utilizing two nodes of the package:
EKF Local Node: Fuses data from an IMU (100Hz) and wheel encoders (4Hz).
...
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EKF of robot_localization have a delay compared to GPS data
I am using ros2 humble and the extended Kalman Filter from the robot_localization package to get both the odom -> base_link and ...
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EKFSLAM with LiDAR and IMU + GPS localization module
There are many resources that relate to EKFSLAM based on the presence of only a LiDAR unit, which localize both the vehicle and the detected landmarks.
I see that they often use state vectors that get ...
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1
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98
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robot_localization GPS causing large drift/covariance spike
I am trying to implement the dual ekf navsat example on my real-world robot. The local EKF with wheel odometry and IMU works quite well and has no issues. As far as I can tell, my global EKF ...
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navsat_transform node doesn't publish utm_transform
Hi, please, help me with following issue, i've been trying to solve it for a week already...
Can't make my navsat_transform node publishing utm_transform.
And odometry/filtered from EKF always has ...
Dan__2022
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robot_localization dual_ekf with GPS: change utm -> map tranform during runtime?
I am wondering if anybody has tried to dynamically change the utm/world -> map transform in a robot_localization dual-ekf setup (with GPS data).
Will it break the nodes behaviour?
The reason for ...
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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?
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MPU6050 providing gyroscope values for linear acceleration
I am using this ROS2 driver to connect my MPU6050 to RPi 4 running ROS2 humble. It outputs an IMU message containing linear acceleration and angular velocity. The linear acceleration values seem to be ...
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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....
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Issue in using IMU MPU 6050
Hello, I have been trying to implement MPU 6050 imu sensor using, MPU SERIAL NODE , when i initially run the node, IMU values seem fine, for example, linear accelerations in x, y, z directions come to ...
Rahulwashere
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What is the purpose of splitting SLAM odom and EKF odom frames in waypoint_nav?
I have a robot somewhat similar to the clearpath husky . In their gmapping launch file, they have their odom frame set to 'odom_gmapping'. config shown here:
...
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[Robot Localization] How to use absolute orientation from IMU with absolut positionning from visual SLAM
Hi,
I'm quite new to ROS and robot_localization so I'm getting confused really fast with TFs. I've been using for some time now a visual SLAM algorithm that works fine and I'd like to slowly improve ...
mathislm
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Nonlinear continuous system function of IMU sensor fusion robot
For my robotics course I have to implement the nonlinear continuous system function for a mobile robot that is equipped with a GPS receiver and an IMU consisting of an accelerometer and a gyroscope. ...
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Jiggling tf Tree After fusing Odometry with IMU
I am using ROS NOETIC and Pioneer3DX as the mobile robot which publishes Odometry info into /RosAria/pose topic as nav_msgs/Odometry message.
Phidgets Spatial IMU is being used which published the IMU ...
pavan_c
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what exactly is 'observation model' for a robot
In my journey to understand the Kalman filter, I understood how a state model representation is derived for a robot and why(to get the robot state for a given input u) it is required.
$$
\boldsymbol{...
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Confused with EKF Localization
I have been trying to understand EKF localization from Probabilistic Robotics by Thrun Burgard and Fox.
There the covariance prediction is given by
$$\overline{\Sigma }_t=G_t\Sigma_{t-1}G^T_t+V_tM_{t-...
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Why is the EKF approximated this way?
I'm a student that recently started taking a course on cognitive robotics. The book I use is Probabilistic Robotics by Thrun Burgard and Fox.
In the EKF algorithm, we linearized the action model in ...
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EKF slam loop closure and landmark location updates
I asked a variation of the question before but I never got an answer.
Basically I'm trying to understand how after loop closure the location of prior seen landmarks gets updated and their uncertainty ...
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Extended Kalman Filter and PID controller
I'm trying to build a model based on tracking an object in 2-D using MATLAB (time-varying system).
I built the model using an Extended Kalman Filter and a PID controller.
I have a doubt regards the ...
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Robot_localization ekf node does not subscribe to Odom topic
Hello,
I am trying to fuse my odometry from my 2D differential drive robot, with my imu using the ekf from RL. The odometry works fine on it's own, but I think I must be missing something simple in my ...
LiquidTurtle1
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9
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IMU sensor coordinates for EKF
Hi, I am using ekf to fuse multiple IMU. I was reading this portion
...
MrOCW
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Derivation of EKF slam landmark initialization
I have read a couple posts which gives the formula for initializing a new landmark in EKF slam but the derivation is not given.
EKF-SLAM initialize new landmark in covariance matrix
Could someone ...
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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" ...
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EKF slam vs global bundle adjustment
How does EKF slam and the covariance matrix interact with global bundle adjustment?
In particular the covariance matrix gives you a confidence on location but global bundle adjustment does not. How do ...
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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 ...
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robot_pose_ekf won't publish any messages
I am having trouble getting the robot_pose_ekf package to publish messages. I launch it with this launch file.
...
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1
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how to use IMU sensor with relative orientation data in navsat transform node
Hi,
I am working on fusing visual odometry, IMU, and gps sensor by using a robot localization package. There are a couple of issues with my IMU data 1) it's not giving absolute orientation or heading ...
rcbot
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Derive the system's dynamics function and the Jacobian Matrix G of Extended Kalman Filter of a differential drive robot on a 2D plane
I have found the following answer on the system's dynamics function and what the Jacobian matrix G of the Extended Kalman Filter look like for a 2D robot with a differential drive. Taken from slides ...
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EKF start to predict after amcl stop sending pose
Hello,
I'm trying to use robot_localization to fuse amcl_pose with encoder odom, and latter GPS.
The experiment is basing on Turtlebot3, gazebo and ros2-foxy.
It's working well if the robot is moving.
...
xingjl6280
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navsat_transform_node geographicErr
Hello,
I am usinf the robot_localization_package to localize a differential drive robot. In my setup, I follow the guidelines of the package documentation about fusing the GPS with dead reckoning and ...
GiacomoDario
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robot_localization (ekf node) output is not stable for a long time
Hi. I am using ekf_localization_node for fusing imu, wheel odometry and amcl_pose ( My config is as follow )
The reason why i am using amcl_pose; When i use ...
Fuat Akca
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1
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279
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No difference between UKF and EKF for SLAM
I built EKF and UKF SLAM algorithms. The problem is that I expected to see a difference because of the more precise approximation of the system in the UKF.
Here's a screenshot from the estimated path ...
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robot_localization IMU yaw velocity causes vertical drift
Hi,
I am using robot_localization's EKF node with my robot's wheel odometry and an IMU. My configuration file is the following:
...
anonymous58627
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53
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SLAM - Angle calculation failure ?-EKF
i am currently building up a EKF SLAM. I dont know where my mistake is but i think it has something to do with the angle my robot is driving towards but im not completly sure. First i thought it could ...
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seeking clarity regarding the 'world_frame' parameter in ekf_localization node
I have spawned two husky bots (namespaced husky_1 and husky_2) in the Gazebo world. I am ...
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EKF Update Step measurement data doesnt fit state vector
I have an EKF SLAM Algorithm which tries to estimate the robots position (X,Y,Theta) + the X,Y coordinates of several landmarks. Like in the posted algorithm i have a range/bearing sensor. I ...
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Using only velocity in robot_localization
Hey guys,
I'm using robot_localization ekf on ROS2 Foxy to fuse two odometry sources. I am working in 2D so only x, y and yaw is used and the two_d_mode is set to true.
I was trying to use only the ...
pfedom
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EKF SLAM Prediction Step
My question relates to the prediction step in EKF SLAM when we get measurements. This is a question I've encountered while implementing EKF SLAM in ROS.
At the beginning of the SLAM loop, we predict ...
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Need help locating 'ekf_localization node' inside 'robot_localization' package
I naviagted to the husky_control package using roscd husky_control. There exists a launch file inside the ...
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What's the correct approach to merging of localization and odometry data?
We've got a mobile platform with a source of odometry and an IMU, which are merged in an EKF filter (robot_localization node), producing continuous odom->base_link transform. The robot is also ...
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Is the covariance matrix in the extended Kalman filter guaranteed to be positive definite (ignoring numerical errors)?
I understand that due to numerical errors (e.g., round off error and machine precision) that the covariance matrix may not be positive definite, but if computers had infinite precision, is the ...
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Why are the state variables passed into the filter not equal to the state variables defined by each [sensor]_config matrix?
I am trying to get a deeper understanding on how ekf_localization_node works.
At the moment I am stuck in interpreting the output of the debug file.
In particular, from the output of that file, I am ...
Roberto Z.
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156
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IMU Vision Fusion using EKF
I am trying to track an object indoors using an IMU (only accel and gyroscope) and a visual marker. This is similar to IMU+GPS fusion, where GPS is effectively replaced by the position that my vision ...
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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,...
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Is there a reason to create set_pose service in global namespace in EKF node?
I'm using robot_localization package under melodic to fuse odom, IMU and GPS RTK data. I followed the tutorials and use two EKFs and navsat_transform node.
I was ...
mpanek06
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53
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State propagation from uncertain control input
Consider a nonlinear system $x(k+1)=f(x(k),u(k))$, where $x(k)\in\mathbb{R}^{n}$ is the state, $u(k)\in\mathbb{R}^m$ is the control input. Here $u(k)$ is normally distributed RV with mean $\mu_u(k)$ ...
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2D Visual-Inertial Extended Kalman Filter
I am trying to implement an Extended Kalman filtering for combining IMU data and visual odometry in a simple 2D case where I have a robot that that can only accelerate in its local forward direction ...
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2
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Kalman filter with missing dimension on measurement input
I am exploring the option of using a EKF with my differential drive robot. I do not have any prior experience with kalman filters.
The robot that is under consideration has two wheel encoders for ...
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LIDAR data rotates when using EKF from Robot Localization
Hi!
We've been trying to use the Robot Localization package, and we've been having trouble with the LIDAR data rotating in our map. Here is a video of the observed behavior - https://drive.google.com/...
Sidd