Questions tagged [imu]
Inertial Measurement Unit
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Compensate tractor's (vehicle's) tilts in the GNSS-IMU based system
I have the following setup: a tractor with a dual band antenna (from ublox) installed on the vehicle's symmetry axis on the roof (h=3m), approx. 1m ahead of the center of the rear axis (which I ...
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The choice of using quaternions and using gyro & accel separately in EKF
I am working on realising the self-navigation of a vehicle.
I have already written an extended Kalman filter with a state vector using position, velocity, Euler angle, acceleration, and angular ...
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Why new/recommended MEMS IMU for AHRS for drones are 6-DOF instead of 9-DOF?
I'm developing an quadcopter as an DIY project.
I'm in nascent stage of development.
I've just finalized the design/working philosophy.
I'm planning to fuse data from 9-DOF (9-Axes) IMU + GNSS + ...
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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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Do MEMS or optical gyroscope record Earth's rotational and revolutional angular velocities?
I am using a 3 axis gyroscope (Android device) to record angular velocities using a sensor data logger application.
When the device is placed stationary, the gyroscope recorded the following values:
...
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What should I use for a Visual+IMU+GPS fusion? A Madgwick or a Kalman?
I am new to robotics, and recently I am involving in a sensor fusion task using visual input (binocular at present), an IMU, and a GPS module. I have searched for related journal papers for a ...
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Why do we need to know the translation between Camera and IMU?
In Visual Inertial Odometry, assuming the camera and the IMU are attached to the same rigid body, why isn't it enough to know just the relative rotation between the camera and the IMU? Why do we need ...
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How to deal with asynchronous samples in a kalman filter framework multi-sensor fusion?
I have setup a sensor fusion problem to estimate a classical 2d position + orientation of a wheeled mobile robot in an embedded environment.
Sensor measurements include:
IMU (6axis accl+gyro) @ 40Hz
...
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SLAM: global BA and IMU rate
My understanding is that in SLAM systems keyframes are recorded at a lower rate and used for loop closing and global BA vs every every image which is used for a sliding window optimization.
What I am ...
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Calculation of IMU offset for Placement of Inertial measurement unit away from centre of mass
I am working on a 6DOF IMU that contains a 3-axis accelerometer and a 3-axis gyroscope. I am building a project to plot the position and orientation of a vehicle/dirt bike in a 3d plane. However, the ...
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accelerometer and gyroscope fusion using extended kalman filter
I'm working on my graduation project which is characterizing human body posture. I'm using IMU so I get measurements from the accelerometer and gyroscope and I'm wealing to fuse these two filters so I ...
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151
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Center of gravity offset for accelerometer and gyroscope readings
I am working on a 6DOF IMU that contains a 3 Axis Accelerometer and a 3 Axis Gyroscope.
I am building a project to plot the position and orientation of the turret/cabin in a crane in 3D space.
The IMU ...
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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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How to read the map output file generated by a project using Cartographer without ROS
Currently I can successfully generate the map output file but I have no idea how to display it in practice. Basically, it should be a 2D SLAM map.
The project I'm using is available at the following ...
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IMU to Camera transformation
Suppose you are implementing SLAM or VIO system, you have your camera C and IMU and a coordinate transformation between them (R, T).
How do convert IMU measurements to camera accelerations and ...
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transform IMU reference to robot reference
I have an IMU rigidly attached to the end effector of a robotic arm. The goal is to compare the orientation of the IMU to the orientation of the robot arm. The 9-axis IMU data is used in a sensor ...
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Opposite direction of rotation calculated by Gyro and Accelerometer
I have just started learning how to fuse the data measured by the gyro and accelerometer to estimate the attitude of an IMU in Matlab. I have no problem estimating or understanding the Euler angles ...
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Simulate GPS IMU With Quadcopter Swarm?
I have multiple drones work in swarm formation, i made the quadcopter model and the swarm one. Until now i have the swarm moving in a formation leader-follower and track a predefined trajectory based ...
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Suggest me an IMU which is not affected by magnetic field
I am using IMU for platform stabilization (Stewart Platform). But the issue is that there is a strong changing magnetic field. And I think that it might affect the accuracy of IMUs. Any suggestions?
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Using an IMU to determine the axis about which it is being rotated
I've got a 6DOF IMU and have, using some trig and and a few references such as ADI's app note: https://www.analog.com/en/app-notes/an-1057.html successfully implemented some Arduino/C code to ...
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Question about 4-mecanum wheeled mobile robots
I'm trying to make a mobile robot with 4 mecanum wheels. The method that I've chosen is to fuse the sensors(encoder, imu) with EKF and use the SLAM algorithms(Gmapping, Cartographer, etc..). Right now ...
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How to fuse IMU with encoders in EKF
Background
I have a car-like mobile robot (4 wheels, where the forward ones are steering wheels) and I want to estimate its pose and velocity assuming 2D planar motion. I'm trying to solve this ...
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My LSM303 magnetometer values are stuck
My Raspberry Pi Pico is connected to a 9 DOF IMU like this one, Adafruit 9-DOF IMU Breakout - L3GD20H + LSM303, through an I2C connection.
For some reason, whenever I try and get values from the ...
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Get rotation of IMU data snapshot
I received snippets of data of an IMU with 9 DoF in motion. For these I wanted to get their rotation by angles relative to the earth frame. My goal is to receive ...
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181
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remove gravity from acceleration on Myo armband IMU measurements
I'm working with the Myo armband through the myo_ros package. The device is able to provide IMU measurements comprising orientation, linear acceleration and angular velocity. The orientation is ...
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Imu orieantation data increase by oneself
I subscriber imu data and print it from my python script.I move imu sensor fast then stop the move but imu data still increasing by oneself. How can I slove this problem?
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How to perform time-offset calibration use GTSAM in Camera-IMU system?
Assume we have camera poses data and IMU data(which include gyr and acc data) with different timestamps, now I want to estimate this value, I known that this can be done in many ways(EKF,MSCKF), but I ...
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PID controller for slowly varying system [duplicate]
I am making a robot that is required to move in a straight line, but it is slowly turning on the left or right, this error keeps accumulating (eventually resulting in a very large radius turn). So, ...
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Nao robot IMU data rates
I'm trying to stream data from the Nao's inertial unit in its trunk. However the update rate is quite slow ~ 1Hz. Is there any way to improve it? For reference, I issued the following command using ...
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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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How do you rotate positions from ENU-frame to body frame?
If positions are in the local frame of ENU (or ECEF - either works), how do you rotate that to the body frame of the device?
Logically, I thought that I could use the pitch, roll, and yaw angles of ...
user31870
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Incorporating motion model in Graph Slam and Bundle adjustment
When doing global bundle adjustment how does one incorporate a motion model or IMU information?
Does it simply impose a cost function in relation to how far away the expected location is of the robot ...
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Mapping IMU readings from body frame to navigation frame
I'm trying to combine IMU displacements with the time of flight sensor readings in order to navigate through the indoor environment with a non-linear Kalman filter variant. In the graphic below, I ...
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What is the consquence of Gimbal lock?
I'm learning about Gimbal lock and I understand the reason why that happened.
But I don't understand why that is a big deal because it only affect this rotation. After this rotation finished, we have ...
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Could hall encoders that are attached to the DC motors affect each other or the IMUs?
I am a newbie and I want to build an autonomous mobile robot. I am planning to use 4 DC motors with hall-effect encoders. I will use 4 IMUs for localization at first. Next, I also have the plan to ...
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Uncontrolled drift of Visual Inertial Odometry
I'm trying to use the VINS-Fusion package to obtain odometry for a quadcopter. The primary sensor is an Intel Realsense D435i. I've calibrated the camera and IMU extrinsics using Kalibr. IMU ...
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IMU Senosr fusion algorithm of gyro and accelerometer during acceleration of vehicle
Hello so we have a car with 10 IMUs mounted at different locations of the car and the idea is the measure the centripetal force at each location of the car and compare it to each other. We also need ...
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What exactly is meant by the "Bias instability over temperature range" specification on IMUs?
I'm trying to become educated on IMU specifications, and my understanding is that when comparing IMUs, the Gyros make the big difference. I am looking at the InertialLabs IMU-Nav-100:
https://...
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Why does the HG4930 IMU have better specifications than the HG1700, even though it's almost certainly worse?
I was browsing and looking at different IMUs and came upon the following Honeywell page:
https://aerospace.honeywell.com/us/en/learn/products/sensors/inertial-measurement-units
There they have a table ...
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Compensation of sudden impacts/shocks in adaptive AHRS sensor fusion algorithms
Background
I have a 9-DOF MEMS-IMU and trying to estimate the orientation (roll, pitch and yaw) in scenarios (e.g. car crash) where sudden shocks (mainly linear) lead to high external accelerations ...
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Why doesn't yaw angle return to its 0 state after rotations?
I'm using STM32F4 mcu with MPU6050 on it. I want to get very accurate yaw angle using gyroscope with Madgwick filter. I tried lots of things: with and without gyro thresholds, with and without ...
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Sensor fusion with extended Kalman filter for roll and pitch
I'm trying to implement an extended Kalman filter to fuse accelerometer and gyroscope data to estimate roll ($\phi$) and pitch ($\theta$). I've found a lot of kalman filter questions but couldn't find ...
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GPS + IMU data and kinematics equations
I have the following data
Longitudinal acceleration, $a_x^{IMU}$
Lateral acceleration, $a_y^{IMU}$
Vertical acceleration, $a_z^{IMU}$
Yaw angle, $\psi$
Yaw rate, $\dot{\psi}$
Latitude, $\rightarrow ...
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Do electromagnets affect magnetometer calibration?
I am designing a landing pad for a drone that will have electromagnets built into the pad. My drone has a pixhawk 2 with PX4. I'm worried that the electromagnets in the pad will throw off the drone's ...
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Why does AHRS system with Madgwick filter has so big drift?
I have an MPU9250 on my PCB and I use an AHRS system with a Madgwick filter to get yaw angle. I want to get very accurate and non-drifting yaw angle, but, for unknown reasons, I can't.
I calibrated ...
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How to calibrate a magnetometer on a heavy robot
I am wondering how to calibrate a magnetometer on an IMU that is installed on a heavy robot. Normally, hard and soft iron calibration is done by spinning the IMU in all axis, but since it is installed ...
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How to use Quaternion from IMU to get the transformation to inertial reference frame?
Im trying to get the Linear Velocity integrating the acceleration from IMu. I know there will be accumulated error due to integration bit before the integration I have to do couple of other steps.
...
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What would be a way to estimate IMU noise covariance matrix?
Weirdly enough, my robot platform which has an official ROS package supported by a manufacturer doesn't provide any covariance matrices of its sensors. So, I'm basically trying to estimate these ...
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C++ (ROS node) for Euler Integration to estimate Velocity knowing the acceleration
Hi I have IMU reading and would like to estimate the linear Velocity knowing the linear acceleration from the IMU using the Euler method. Im aware of the accumulated error. So need a C++(python) code ...
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Sensor fusion in a metal heavy environment
I am trying to get heading information of a forklift. I've designed a small PCB for this purpose. This PCB has a 3 axis magnetometer and a 6 axis gyroscope-accelerometer (Z- axis looking towards the ...
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