Questions tagged [magnetometer]
A magnetometer is an instrument that measures magnetism—either magnetization of magnetic material like a ferromagnet, or the strength and, in some cases, direction of the magnetic field at a point in space
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Finding North direction from magnetometer and accelerometer fusion
I was understanding accelerometer and gyro sensor fusion from this video. At time 3:56, Brian says:
To get north, we need to do some cross products. We can start with our measured mag (magnetometer) ...
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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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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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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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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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Digital compass precision in urban environment
I'm working on an application to compute the absolute heading (yaw) using the following hardware: WIT-Motion HWT905 IMU https://www.wit-motion.com/digital-inclinometer/witmotion-hwt905-ttl.html. It ...
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Can a Madgwick IMU filter be used to determinate the tilt angle with respect to the horizontal plane
I am using a 3-axis accelerometer and a 3-axis gyroscope to estimate the tilte angle between the X axis of the IMU sensor and the ground (horizontal plane). My robot is stationary at power up, so I ...
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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 ...
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How to set initial heading
I'm confused how to set up an initial heading for my mobile robot project. I've determined heading from gyro integration and also using magnetometer readings. Gyro initializes at 0 and magnetometer ...
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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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How to create a Complementary Filter for a linearly accelerating body to obtain estimate of orientation in quaternion?
A complementary filter (CF) uses orientation obtained calculated from gyroscope, accelerometer and magnetometer to find a more accurate measurement of orientation.
However, when my sensor is ...
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Does GY-271 (HMC5583L) or any 3-axis magnetometer suitable to detect orientation?
Based on the datasheet, HMC5583L has 160Hz output rate and produce three axis direction angle data, X, Y, and Z. It can measure diversion from Earth magnet field with 1° to 2° accuracy. Does that ...
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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 ...
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Interfacing HMC5883l Compass with Arduino
I'm using an HMC5883l compass module to find the angle at which my module is pointed from magnetic North. I found this code as an example with "HMC5883L_Simple.h" library.
And the results I'm getting ...
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Combining gyroscope and compass to navigate in cities?
I am developing a navigation app which combines compass and gyroscope to withstand magnetic field disturbances which can be found in cities.
I am able to know what the magnetic field is supposed to ...
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How to transform raw accelerometer data into the Earth fixed frame to determine position
I have data from a TeleMega and do not understand how to apply the rotation matrix for the accelerometer data so that I can get the more accurate position estimate from my accelerometer. My data comes ...
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How to add a magnetometer in an Extended Kalman filter for innovation update?
I can't find out the response so I am posting here.
My post kind of follow this one : Adding magnetic field vector to a Kalman filter
but I already know that I don't have to put the magnetometer in a ...
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Noisy magnetometer data
I’m looking to develop an AHRS for which I’m using a magnetometer to correct for heading errors. I wanted to check that the magnetometer I'm using is functioning to the level of accuracy (+- 1 degree) ...
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Magnetometer Calibration
I'm looking at using a magnetometer in a project and I'm struggling to understand the proper procedure for calibration of the sensor.
I understand that magnetometers need to be calibrated to ...
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Orientation from magnetometer data
I saw lot of topics with the same title but answers are different.
I have a magnetometer in my phone which give me the components of magnetic field in direction of X, Y, Z.
If my phone lays on a ...
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Can a mu-metal enclosed compass measure the earth's field?
I am thinking about using a combination of mu-metal, a faraday cage, and spacial separation to reduce magnetic interference from a brushless motor on a compass sensor.
The compass will be used to ...
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Practicality of using magnetometer inside AUV
I have an AUV with a 12 inch diameter, 29 inch long capsule. Inside the capsule sits an Intel NUC computer, an NVIDIA Jetson GPU, an Arduino Mega, a Sparton IMU (9 DOF) as well as a custom voltage ...
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How would i implement position and heading readings into my SLAM system?
I am trying to build a low-cost SLAM system with an MPU-6050 and GY-271 (magnetometer). Currently, i have a robot with an Arduino that collects the sensor data and a Raspberry Pi that (hopefully) will ...
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Kalman Filter GPS + IMU
I know this probably has been asked a thousand times but I'm trying to integrate a GPS + Imu (which has a gyro, acc, and magnetometer) with an Extended kalman filter to get a better localization in my ...
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Adding magnetic field vector to a Kalman filter
I currently have an error state Kalman filter with the state vector $(p, v, q, \omega, a, g)$ where $q$ is the quaternion orientation. I would like to add the information coming from a magnetometer to ...
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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,...
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What are the specifications of the digital compass used in iPhone 6S
What are the specifications of the digital compass used in the iPhone 6S?
I am trying to measure yaw angle using the magnetometer. I observed the magnetometer/digital compass in the iPhone is really ...
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Quadcopter heading calculation
I'm working on an autonomous quad copter, I have two GPS co-ordinates (source and destination co-ordinates). I need to move my quad from the source to the destination, for this I need to calculate the ...
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Why would a drone need a magnetometer? Are an accelerometer and a gyroscope not sufficient?
Why would a drone need a magnetometer? What would the drone do with this information? I think it would be to tell direction, but why would it need this if it has an accelerometer and a gyroscope?
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Is there a way to measure 3 axis orientation without a magnetometer?
I have bought an STM iNEMO evaluation board in order to monitor the inclination of a separate magnetic sensor array as it moves in a linear scan outside of a (non-magnetic) stainless steel pipe. I ...
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Weird magnetometer values
I bought a 3-axis magnetometer (Similar to this one ) And plugged into an Arduino in order to read the heading value.
I mounted it on my robot and I drove with the robot for around 30 meters, turned ...
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Robot wire follower + how to position on wire
I'm designing my lawn mower robot, and I am in the perimeter stage.
The electronic part is done, and works quite good, now comes the software.
I need an advice on how to deal with the problem of ...
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Sensor orientation of an external magnetometer [closed]
On many drones are already external magnetometers. Unfortunately, the orientation of such sensors is sometimes unknown. E.g. the sensor can be tilted 180° (pitch/roll) or X° in yaw. I was wondering, ...
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Axis of rotation via IMU
Using an IMU (gyro, accelerometer and magnetometer), as found in most smartphones, can I detect the differences between tilting the device, say forward, along different (parallel) axis positions?
To ...
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FreeIMU External Magnetometer
I have been using the FreeIMU library successfully but now I want to add an external magnetometer that I can mount away from my motors.
I've figured out how to modify the FreeIMU library to use an ...
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3-axis Magnetometer Question
Apologies if this is a stupid question, but if I have a 3-axis magnetometer, and I calculate the vector magnitude as
sqrt(magX * magX + magY * magY + magZ * magZ)
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3D Magnetometer calibration algorithm
I want to calibrate my compass, which is installed on a board which inherits a GPS module. Because the GPS antenna is up-side-down the compass is 180° inverted. The easiest way to correct the problem ...
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Tilt-compensated compass - at my wits' end
I'm a bit at my wits' end here - I'm trying to build a tilt compensated compass for my autonomous sailboat (ardusailor!). I'm using an InvenSense MPU9150. Originally, I used the built-in fusion ...
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How to determine the parameter of a Complementary Filter?
I know that the Complementary Filter has the functions of both LPF and HPF. But I think my understanding on the principal behind it is still unclear.
I am quite new on digital signal processing, and ...
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How are units of noise measurement related to units of a sensor's data measurement?
I'm trying to understand how noise is represented for accelerometers, gyroscopes, and magnetometers so that I can match the requirements of my project with the standard specs of these sensors.
I ...
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