Questions tagged [imu]

Inertial Measurement Unit

51 questions with no upvoted or accepted answers
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8
votes
1answer
6k views

Angle Random Walk vs. Rate Noise Density (MPU6050)

I’ve made a datalog from a MPU6050 (IMU: gyroscope and accelerometer) at 500Hz sample rate. Now I want to calculate the characteristics from the gyro to evaluate the sensor. For the gyro I’ve found ...
5
votes
1answer
253 views

Inferring joint orientation on multi-joint arm

Not a robotics question in the strictest sense, I guess, but related closely enough, I hope: I have an arm-like articulated two(-plus-one)-joint appliance that I want to use as a 3D input device. It ...
4
votes
1answer
397 views

MPU6050: Changing Gyro Output Range Throws off Positional Reading

I am using the MPU6050 in conjunction with an Arduino and Jeff Rowberg's i2cdev library, and my project requires that the gyro rate outputs be more precise than the default setting, which is 1/16.4 of ...
3
votes
2answers
980 views

Correctly calculating free acceleration given NED referenced orientation quaternion and sensor referenced acceleration data

I have a sensor outputting correct, calibrated North-East-Down referenced quaternions describing the orientation of the sensor. It also outputs raw, sensor referenced acceleration data, inclusive of ...
3
votes
1answer
163 views

How is the GPS fused with IMU in a kalman filter?

I've been trying to understand how a Kalman filter used in navigation without much success, my questions are: The gps outputs latitude, longitude and velocity. While the IMU outputs acceleration and ...
2
votes
1answer
87 views

Particle Filter for IMU tilt angle and bias estimation from Kalman Filter models

I understand the functioning of Particle Filters from the book Probabilistic Robotics and the robotics course provided by Cyrill Stachniss. I want to implement, from scratch, a particle filter to ...
2
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0answers
204 views

How to estimate yaw angle from magnetometer and gyroscope?

I'm using the MPU9250, it measures acceleration, magnetometer, gyro, etc. Complementary filter tutorial for this is here, however this tutorial does not have a magnetometer and I do, thus I thought I ...
2
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0answers
132 views

How to handle sensor data for a sensor-fusion algorithm

I am implementing the explicit complementary filter(see below) with a 9DOF MEMS sensors (accelerometer, magnetometer and gyroscope) for attitude estimation. Currently, the gyro and accel update rates ...
2
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0answers
486 views

How to properly calibrate a magnetometer in IMU for precise yaw?

EDIT: Moved to ElectricalEngineering StackExchange Community I'm using Sparkfun Razor IMU 9DOF sensor which incorporates accelerometer, gyroscope, and magnetometer, for giving the Euler's angles (yaw,...
1
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0answers
13 views

How do you derive the soft iron matrix for magnetometer calibration?

Can someone send reliable sources for how this is derived? I understand the diagonal values are for scale, but how do you determine all 6 values needed for this matrix? I would also like to normalize ...
1
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2answers
36 views

Drone lost traj recovery

So I am using slam algorithm to localize the drone which is gps denied . The input to the slam algo is imu data and a video . Now after the first run of the slam algorithm it creates the trajectory ...
1
vote
1answer
52 views

How to calculate the ground truth of your own simple dataset for testing your SLAM Algorithm?

I have tested my SLAM algorithm on EuRoC, TUM and KITTI Datasets. But I would like to test on my own custom dataset. Moreover, I already rectify how to make my own dataset in TUM dataset format, but I ...
1
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0answers
17 views

What could cause quaternion error to go up drastically when a gyroscope is rotated on more than one axis at a time?

Alright, I'm working on a small Arduino script that determines orientation using a a gyroscope and a quaternion. My hardware: LSM9DS1 IMU (Gyroscope, Accelerometer, Magnetometer) Teensy 4.0 My basic ...
1
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2answers
180 views

Sensor fusion of GNSS and IMU using UKF

I do have a land-based robot with an IMU and a GNSS receiver. From the IMU, I get the velocity and acceleration in both $x$ and $y$ directions. From the GNSS receiver, I get the latitude and ...
1
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2answers
43 views

“catkin_make” prompts “+make” and “recipe for target … failed” errors

I have been working on a ground vehicle project for some time that has bunch of sensors, until now I have managed to overcome the problems I have encountered. I have used catkin_make many times and ...
1
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0answers
28 views

Barometer altitude calculation

I want to calculate altitude using a barometer which is mounted in the proximity of a number of components which get quite hot and raise the localised temperature. The barometric pressure equation is ...
1
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0answers
76 views

Can someone help me understanding reference frames in OxTS data in KITTI Vision Benchmark dataset?

If anyone has worked with KITTI dataset, can you explain the reference frame used in roll pitch yaw values? I downloaded the raw data from this link: http://www.cvlibs.net/datasets/kitti/raw_data.php ...
1
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0answers
40 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 ...
1
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0answers
415 views

Yaw, Pitch, Roll rate concepts and how to calculate them with an IMU

I need help understanding the difference from Y/P/R rate and the data that I can get from a gyroscope. I am using the raw readings of my IMU (MPU9250) and the Madwick Filter to calculate a quaternion ...
1
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0answers
21 views

Yaw from quaternion with non zero pitch

If IMU is gravity aligned, pitch is zero and yaw is unobservable. If IMU is not gravity aligned, pitch is non zero and yaw is observable. Question: given an input quaternion with non null pitch, how ...
1
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1answer
133 views

Complementary filter for gyroscope and accelerometer

I am trying to understand how the complementary filter works. I did some research and i found this: I am confused about the noise and drift before any filter is applied. I have 2 questions: In the ...
1
vote
1answer
185 views

Accelerometer and gyroscope noise and bias

I am doing an EKF (Extended Kalman Filter) to fusion Visual Odometry with IMU information. I am using a ROS package called ethzasl-msf (I am using the multi sensor fusion because then I have to add ...
1
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0answers
59 views

Kalman filter to fuse ultrasonic altitude sensor and accelerometer

I'm a little confused on how to set up the Kalman filter matrices to fuse an ultrasonic altitude sensor and accelerometer from IMU. I am trying to implement this for a quadcopter. And what I'm ...
1
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0answers
61 views

Writing IMU accelerometer data into as twist messages into cmd_vel

I am reading accelerometer data from the wiimote /wiimote/state topic. A sample of the data I'm working with is as follows: ...
1
vote
1answer
677 views

EKF implementation on odometry/IMU

I am applying Extended Kalman Filter for a mobile robot with IMU and odometry data. I am running simulation currently. However, I don't have suitable data for odo/IMU measurements to use. Where can I ...
1
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0answers
272 views

Is it my PID that is unstable or my physical system? (Quadcopter)

I've been working on this Arduino-MPU6050 quadcopter for a while now, and it looks like it's close to being finished. I have programmed it in rate mode, so the PID's control the rotational velocity. ...
1
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0answers
133 views

Using an AR.Drone's IMU to perform PDR

My task is simple: I want to move my drone manually around a room (IMPORTANT: I DO NOT WANT TO FLY IT) and I want to see its position update on a map using IMU data. I've attempted something in ROS ...
1
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0answers
201 views

Accelerometer, gyro, and magnetometer sensor fusion for material resource survey

As a hardware engineer, I have studied quite a lot on sensor spec such as Accel, Gyro and Magnetometer including custom made fluxgate. I have studied matrix and quadarion (complex number) and so on. I ...
1
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0answers
1k views

Orientation parameter for quadcopter with madgwick fusion algorithm

I recently decided to build a quadricopter from scratch using Arduino and now I'm faced with an orientation estimation problem. I bought a cheap 10DOF sensor with 3 axis magnetometer, 3 axis ...
1
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0answers
498 views

Fusion of GNSS position data and prefused 9-dof AHRS data

Bosch, FreeScale, InvenSense, ST and maybe others are releasing 9-dof AHRS platforms containing their own fusion software and outputting filtered/sane/fused data (attitude as quaternion and linear ...
0
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0answers
23 views

How to compute linear speed on scooter without gps and wheel odometry

My project is to be able to compute my linear speed on my scooter only with my IMU. I have a IMU build with my arduino which is in my backpack. I want first to compensate the acceleration measurement ...
0
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0answers
31 views

How is IMU noise dealt with between steps?

Direct integration of IMU will result in massive error incredibly quickly. What I am wondering is, how do you use an IMU over a small time intervals to aid in pose estimation? In particular, suppose ...
0
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0answers
14 views

When Implementing Madgwick filter for attitude estimation, the calculated Euler angles are drifting significantly. What could be the reason?

The Beta value is set according to the original report, which specifies for IMU B-0.033. and the sensor data acquisition and filter update is periodic at 200Hz. The angular velocity values from the ...
0
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0answers
344 views

IMU + GPS fusion and change of reference frame

I started working with GPS + IMU fusion using Kalman Filter. For this, I'm using Python, with Madgwick filter from a library (https://github.com/morgil/madgwick_py) and Kalman filter also from an ...
0
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0answers
48 views

To calculate roll,pitch and yaw

How do I calculate roll,pitch and yaw value from the position co ordinates of the drone, that is x,y and z from the gps sensor??? Using the x,y and z co ordinates I have to calculate roll,pitch and ...
0
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0answers
41 views

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 ...
0
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0answers
30 views

Find IMU's movement direction in x-axis

I have an IMU device with an accelerometer sensor and I fix that on top of the linear motion rail.so it can only move to the right or left (in the x-axis) side. How can I determine the direction (...
0
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0answers
30 views

Angular movement of a controlled arm relative to an object via Two IMUs

I've been tasked to use two YEI 3-space sensors (IMUs) to detect the azimuth and elevation (altitude in the image below) angle of a moving arm with respect to a fixed object, with a sensor on the end ...
0
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0answers
30 views

Angular rate controller

I try to design an attitude controller with cascaded PD-P structure (angle-angular rate) for well-known quadrotor dynamics according to the thesis. I use an imu as expected in order to get the angle(...
0
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2answers
73 views

I2C Arduino Connection

I am working on a wheel mobile robot with multiple sensors which are IMU, two encoders, four ultrasonic sensors, and using two Arduino: Uno and Mega. The IMU, encoders, and ultrasonic sensors are ...
0
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0answers
28 views

MPU6050 Gyro rotaion always around Y axis

I am using an MPU6050 IMU. I did a small experiment having Z-axis pointing upwards. 1. Rotate 90deg around Z-axis (yaw) and back to the original position 2. Rotate 90deg around X-axis (roll) and back ...
0
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0answers
15 views

Gyroscope signal when mounted on a deflated tire

Before I do the experiment, I am a bit confused about the expected signals provided by a 3-axis gyroscope (angular velocities vs. time) mounted on the edge of a (slightly) deflated car tire when the ...
0
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0answers
34 views

Catching drift from IMU with if…else

recently I tried to measure yaw angle with MPU6050 and MahonyAHRS algorithm. As expected, the yaw angle consistently drifts. But I could see that the changes caused by the drift are much smaller ...
0
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1answer
359 views

Gyro yaw drift compensation

I'm looking for some kind of filter, algorithm which will allow me to compensate gyro yaw drift using heading of magnetometer. My project requires only yaw measurments and both sensors are flat. Is ...
0
votes
1answer
212 views

MPU6050 gyroscope giving wrong measure

i am trying to make an angle meter, using the UNO and MPU6050, following joop brokking video tutorials, when utilizing the accelerometer, the results are fine, however when i try to use gyroscope ...
0
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0answers
25 views

Differences between strapdown inertial navigation and motion models

In a state estimation scheme with a simple IMU/GNSS setup using EKF, I have always thought the prediction step would be done using a motion model and all sensor measurements would be incorporated via ...
0
votes
1answer
48 views

Which algorithms to locate a static 3D object relative to a moving camera/IMU?

I am using typical setup with camera and IMU as found on a smartphone. Using this, I would like to estimate the relative pose between the camera and an object (for simplicity, let's say a cube). The ...
0
votes
1answer
180 views

How to do IMU and camera “sensor fusion” tracking?

I have some 50ms latency cameras at hand and a 800Hz IMU (gyro+accelerometer+magnetometer). I would like to know how exactly how I should do a sensor fusion of such an IMU and camera to fix the ...
0
votes
1answer
221 views

What does ardupilot do and how does it do it?

I have been using ardupilot on drones for a while and I don't exactly know what it does. I know it keeps a drone leveled, lets us set way points and automatically fly through them, etc. Is that it? If ...
-1
votes
2answers
241 views

Sensor fusion to calculate joint angles between segments of a robot arm using IMU data

I have an IMU attached to each of the segments of a robotic arm, which gives me accelerometer and gyroscope data. My goal is to first of all improve the quality of the sensor readings and subsequently ...