Robotics Stack Exchange
Robotics Stack Exchange

Questions tagged [imu]

Inertial Measurement Unit

an electronic device that measures and reports its velocity, orientation, and gravitational force

565 questions
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Euler Angles from 9DOF IMU

Using the Adafruit 9DoF module I Need to convert the Accel + Magneto + Gyro into Euler Angles for a motion capture application. Any hints on where to start? Managed to get X,Y,Z when the IMU is facing upward but when that orientation changes the…
user2967920
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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 gravity. I want NED free acceleration, without…
Mauvai
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Does it matter how I mount an IMU board?

I am going through the board's calibration process and it is declaring success. Do I still need to pay attention to how I mount the board, that is, match the x,y,z directions printed on the board?
pitosalas
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Yaw from IMU acceleration

When IMU is gravity aligned, yaw is not observable from linear acceleration data. However, when IMU has non null pitch, the sensor is not gravity aligned anymore and the gravity acceleration gets remapped on other axes. Question: how do you…
Employee
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What information an IMU gives to a drone?

An Inertial Measurement Unit (IMU) is an important sensor used in aerial robotics. A typical IMU will contain an accelerometer and a rate gyroscope. Which of the following information does a robot get from an IMU? Position Orientation Linear…
Revolucion for Monica
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IMU rotate about one axis, other two angles change too

I am trying to use Invensense's MPU9250. I am using provided library to read euler angle. When the IMU rotates about one axis, angles about other two axes change too. What could be potential cause to it?
drerD
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How to calibrate an IMU unit?

Simply , how can I calibrate IMU unit ? I read some papers about this topic and was wondering if there are any standard methods.
xsari3x
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What's the difference between Yaw and Attitude in Quad Rotor

I have a big miss conception between Yaw and attitude ? Isn't both represent "how far is the quad from earth ?" Also if you could post how to calculate them from IMU (gyro +accele + magent )
xsari3x
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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…
JCB
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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 do you extract the observable yaw?
Employee
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IMU oriented wrongly. How to correct it to get correct values?

We have used an SMC-108 IMU sensor in a hydrographic survey. This was our first time using this sensor. While processing the data, we noticed that the roll, pitch, and heave values were not right. Turns out, this IMU sensor has to be aligned in a…
Thoram
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Getting velocity from IMU acceleration

I am doing to research about why you cannot use IMU acceleration the integrate to get velocity. Everyone says you cannot do that due to there being error but what error is this exactly and where does it come from?
shmaugust
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Transforming linear acceleration data of IMU to linear velocity data

Hi, How to transform linear accelerating data of IMU to linear velocity data? I want to obtain linear x and y velocity value from IMU. How can ı do this? Thanks in advance. Originally posted by Mekateng on ROS Answers with karma: 85 on…
Mekateng
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Using the razor_imu_9dof package with the sparkfun IMU (14001)

I'm just wondering if anyone has had any success getting the new version of the Sparkfun 9DoF Razor IMU M0 Board working with the razor_imu_9dof node? I've been trying to get this working for a while now and although I've made some progress it's…
PeteBlackerThe3rd
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What units does the IMU message use?

The docs list some of the units used for the Imu message, but not all. For example, what units are used for orientation Quaternion? I've been setting these to the Euler angles, which I have in degrees, but it's rendering nonsensically in Rviz.…
Cerin
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