Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [imu]

IMU is an abbreviation for Inertial Measurement Unit, a system composed of three orthogonally mounted accelerometers and three orthogonally mounted gyroscopes, which may be used as the basis for inertial navigation systems, orientation measurement systems, or platform stabilization systems.

212 questions
49
votes
1 answer

What are the differences between a gyroscope, accelerometer and magnetometer?

What is the difference between a 3-axis gyroscope, 3-axis accelerometer and 3-axis magnetometer? How do these sensors work? Why are all 3 used in some devices like smartphones, tablets, quadcopters etc.?
Kicsi Mano
  • 819
  • 1
  • 10
  • 23
35
votes
5 answers

How to determine position from gyroscope and accelerometer input?

I have a 3-axis accelerometer and a 2-axis gyroscope. I intend to measure something that only moves in the X and Z axis. I've heard of using Kalman filters to smooth out the acceleration vectors, but I can't find a good tutorial for a complete…
Steven
  • 491
  • 1
  • 5
  • 5
19
votes
1 answer

Magnetometer ∞ shaped calibration

In mobile phones and other devices using a 3-axis electronic compass, a ∞/8/S shaped movement is used to calibrate the magnetometer as shown in these videos. Why is this movement performed, what is the theory, and can anyone give some example C code…
Rick2047
  • 739
  • 8
  • 13
19
votes
2 answers

Magnetometer dynamic calibration

I am working on a Magnetometer AK8975 being a part of an IMU. Which seems to be very tricky for me. This chip gives a 3D vector as output describing earth's magnetic field at any place on earth or near it. I tried two types of heading calculation…
Rick2047
  • 739
  • 8
  • 13
13
votes
4 answers

Limits of dead reckoning using MEMS sensors

I'm trying to track body parts relative to a person's torso. I see quite a few questions about using MEMS accelerometers and gyros for dead reckoning, and they confirm my suspicions that various factors greatly limit their usefulness for these sorts…
Selali Adobor
  • 265
  • 2
  • 7
11
votes
1 answer

AHRS algorithm under continuous linear accelerations

I have tried several algorithms to get pitch, roll and yaw under continuous linear accelerations and vibrations (smaller than 0.4g, frequency lower than 10HZ). None of them give good results because the readings either drift or are affected too much…
Timtianyang
  • 521
  • 2
  • 6
  • 16
11
votes
4 answers

Dead reckoning with accelerometer & gyro. Possible?

I have a 3 axis accelerometer and a 3 axis gyroscope. I've been tasked with developing a dead reckoning system using this hardware. Essentially what's needed is for me to develop some code to track the position in 3d space of the board in real time.…
user41883
  • 111
  • 1
  • 1
  • 5
8
votes
3 answers

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: X: 0.003 Y:0.00042 Z:0.0045 At an instantaneous…
Akash Sagar
  • 91
  • 4
7
votes
4 answers

What affects IMU (Inertial Measurement Unit) accuracy?

Context I need to analyse the performance of a system that uses inertial sensor readings as input. My knowledge of IMUs is very basic, having only read a few introductory texts. My understanding is that IMU accuracy degrades with continuous use due…
Josh
  • 141
  • 1
  • 1
  • 3
6
votes
2 answers

What is the point of this MOSFET?

In the image above, could someone please tell me what the MOSFET is doing? From what I gather, it is there for switching between the VCC_in and the regulated voltage, in conjunction with the SDA and SCL lines. However, if all the components are…
ritchie888
  • 490
  • 2
  • 13
6
votes
2 answers

How can I detect angular movements and disregard lateral movements?

I'm working on a project that involves a flat platform that a user can tilt from side to side and forward and back. I'd like a sensor that can monitor the angle difference between the platform's original position on and its current orientation. Do I…
Bill
  • 355
  • 1
  • 5
  • 10
6
votes
3 answers

What actually causes gyroscope drift in IMU?

I've been researching online to understand how to get gyroscope data from the MPU-6050 which is probably one of the most popular IMU's out there. But i am confused over the reason why the gyroscope drifts, as i found two sources which give different…
DryRun
  • 541
  • 1
  • 7
  • 16
6
votes
1 answer

Using an inertial measurement unit to compute global motion optical flow of video

I have a camera rigidly mounted together with an IMU that consists of 2-dof gyroscopes and 3-dof accelerometers. My aim is to compute the global optical flow of the image captured by the camera, in order to do global motion compensation when…
Ang Zhi Ping
  • 577
  • 1
  • 6
  • 14
6
votes
1 answer

Accessing magnetometer results in MPU-9250

I am interfacing an MPU-9250 to an STM8S207 microcontroller. The MPU-9250 is accessed via 400kHz I2C. I have no isses with getting measurement data from the temperature, gyro and accelerometer, but can not get the built-in AK8963 magnetometer…
maszoka
  • 91
  • 1
  • 5
5
votes
3 answers

IMU BNO055 Alternative?

For a robotic application, we bought Adafruit boards of the very popular BNO055 IMU. We can still buy plenty of these modules, but it seems the BNO055 chip itself is unavailable. It even disappeared from the Bosch website without any…
nowox
  • 477
  • 4
  • 12
1
2 3
…
14 15