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.

Filter by
Sorted by
Tagged with
0
votes
0answers
57 views

Driving a motor freezes Arduino

I am trying to drive a Carrera Digital car (brushless DC motor) using an Arduino and an L293D h-bridge motor driver. My schematic is the following: I have also connected an IMU (GY-521 MPU-6050) to ...
0
votes
1answer
40 views

Sensor fusion using IMU sensor

How to do the sensor fusion using the 4 IMU sensors. Here, 4 IMU sensors are used to know the location of every point where the IMUs are placed? I need the location of the every point on a 3D graph ...
2
votes
2answers
57 views

Looking for gyroscope drift spec in datasheet

The product page of the BMI088 IMU makes the very impressive claim The automotive-proven gyroscope of the BMI088 has an unmatched bias stability of less than 2°/h However, I can't find this claim ...
1
vote
1answer
41 views

Mount position inertial measurement units (IMU)

currently I am reading about IMUs and got confused about the mounting position of the IMUs. In this paper (https://pdfs.semanticscholar.org/c2b6/9d5f4cf0fbbbad97d1fc10b3757f9c41bb8f.pdf) , the ...
0
votes
2answers
81 views

How can you estimate the final position of a gyroscope graphically?

A Smartphone is initially in the position indicated as follow We move it, and get the next gyro reading. How can you estimate your final position graphically?
0
votes
0answers
53 views

Gathering accelerometer data over I2C not updating every 1 ms

I am using an STM microchip to communicate with an IMU over I2C. I am requesting 3 axis of acceleration information from the IMU (x,y,z). I have the ODR Selection frequency set at 1.66 kHz. Currently ...
1
vote
2answers
47 views

How is Gyro drift error related to error in velocity and position?

While reading about IMU on wikipedia I found this about its disadvantages: "A constant error in attitude rate (gyro) results in a quadratic error in velocity and a cubic error growth in position." ...
1
vote
3answers
223 views

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 ...
0
votes
0answers
42 views

MPU9250 magnetometer values freeze after some time

Setup: I am working on a system where multiple MPU9250 IMUs (6, to be specific) are connected to an ESP32 MCU via SPI. Using SPI as the communication bus is crucial because the I2C pins are occupied. ...
0
votes
3answers
82 views

Implementing Honeywell IMU

Want to start by saying I'm a mechanical/aerospace engineer, and I'm fairly out of my depth here. My current project is on a load-testing rig. Ultimately, it will use a Honeywell HG1120 IMU to give ...
1
vote
0answers
33 views

How does the timing of the MPU9250 works?

I am using an MPU9250 in my project and I am struggling with the timing domains of the various sensors. Let's say I have the magnetometer ticking at 100Hz, the Gyroscope at 32kHz and the accelerometer ...
1
vote
0answers
75 views

Quarternion disagreement between two BNO80 IMU

I'm trying to use two BNO80 orientation sensors to measure the deflection of a universal joint in both pitch and yaw (there are components in the way that prevent the use of rotary position sensors). ...
1
vote
1answer
120 views

Serial Peripheral Interface (SPI) vs Two-Wire Interface (TWI, I²C) wire length

I'm using Arduino DUE to read data from an IMU(inertial measurement unit) sensor (MIKROE-1577, MPU-6000) This IMU sensor supports both Serial Peripheral Interface (SPI) and Two-Wire Interface (TWI, I²...
0
votes
0answers
27 views

Bluetooth sensor on sports field - multiple antennas

I am creating a tracking project for lacrosse sticks that uses an IMU to give the absolute position of the stick. The goal is to use it to guess the speed of the ball shot, and I will use that as a ...
1
vote
0answers
66 views

How to get relative rotation matrix from two consecutive orientations of MPU6050

I need to find the relative rotation matrix between two orientations of MPU6050. My approach (which fails) uses the MPU6050 quaternion from jrowbergs code. Let quaternion at orientation 1 be q1 & ...
1
vote
0answers
79 views

Gyroscope drift in IMU

So, a brief foreword. I'm not sure if this question belongs here or in the DSP community, its closely related to both, but I have a feeling this will be more of interest here nonetheless, so I am ...
2
votes
0answers
160 views

ESP8266 sleep current is higher than it should be [closed]

In short: Despite setting my datalogger IMU to SLEEP and going to deepSleep(0) on the ESP without any other IC peripherals besides the buck converter and 2 deactivated LEDs, I still measure 2.5mA ...
1
vote
0answers
162 views

Measure relative position between two IMUs

I'm trying to create a system where I need to measure the relative orientation of the edge of the arm with respect to its base: The apparatus will be like in the diagram above. To measure the ...
0
votes
2answers
513 views

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

I have some 50ms latency cameras on hand and an gyro+accelerometer+magnetometer 800Hz IMU. I would like to know how exactly I should do a sensor fusion of such an IMU and camera to fix the positional ...
0
votes
2answers
257 views

how reliable are IMUs for a long usage (6 hours) rotation (only) tracking? [closed]

I know they are bad for positional tracking and drift from actual position over time but would like to know what is the situation with rotation only. I know Oculus DK1 used ordinary off the shelf ...
0
votes
1answer
170 views

LSM9DS1 accelerometer with too many aux pins. Which ones are actually useful?

I'm designign a board with an LSM9DS1. I have an SPI bus (with only this device connected), two gpio for the chip selects (it has two CS, one for gyro and accel and the other for the magnetometer. ...
2
votes
1answer
463 views

Double Integration with the BNO055 for position data

I am trying to get position data(x, y, z) from the BNO055 IMU from adafruit. I have been given a library in java, so I can communicate with the IMU. I have been able to get heading, yaw, pitch to +/- ...
1
vote
0answers
121 views

Calculation of Euler angles. But gets a change (delta) in change and not a constant value

What I've done will now: I'm using an IMU (MPU6000) to calculate the Euler angles of an object and for this, I'm using Madgwick AHRS algorithm. The MPU gives acceleration due to gravity (a) about the ...
0
votes
1answer
219 views

How to connect a 4-pin OSC (crystal oscillator) to an IMU (BNO055) with only 2 pins dedicated to an external clock?

I am using the BNO055 : https://cdn-shop.adafruit.com/datasheets/BST_BNO055_DS000_12.pdf and I can't seem to figure out how to connect a standard external oscillator clock to the chip. As suggested, ...
0
votes
2answers
2k views

How to choose a cut-off frequency by interpreting FFT

I have a question concerning low pass filtering of IMU acceleration and gyro data. To choose a reasonable cut-off frequency, I thought about making some observations in the spectrum. Now I have some ...
1
vote
0answers
89 views

How to improve AHRS algorithm

I'm currently working on a project with multiple IMUs mounted on moving vehicle estimating their pose. I've just read about AHRS algorithms. So I have two questions about them: Since my data is pre-...
0
votes
1answer
1k views

MPU6050 showing inconsistent angle values

I'm using this Arduino code to calibrate and read from an MPU6050 accel/gyro sensor from an Arduino Mega. The calibration and reading of values seemed to go well. However, I'm seeing some ...
0
votes
0answers
100 views

Measuring pitch under dynamic acceleration: better to use 6DOF sensor or 9DOF?

I am working on a project that is challenging me. I've researched on the subject as best I can, but would like additional opinions. I have a 4' long aluminum c-channel (essentially, a metal rod) with ...
0
votes
2answers
102 views

Optimal sensor for measuring object velocity in an open area?

I am trying to measure vertical and horizontal speed of an object attached to a parachute. It will be launched from a low altitude and in an open area, allowing satellite GPS lock. Data treatment ...
0
votes
1answer
185 views

How can I keep stable position of my drone? How can I detect bias of them?

I am just a little bit worried about my research because I feel stuck in one point and I can't find the exit door. My question is about this: I will design a drone and the professor wants that ...
1
vote
1answer
131 views

MPU-9150 (IMU) AD0 address change

I have an MPU-9150 which uses I2C address 0x68 by default, but I'd like it to use address 0x69. This is possible by desoldering the 3-way AD0 "Jumper" on the breakout board. By default there are 3 ...
1
vote
1answer
158 views

Allan std deviation: why do we need to read the values at specific sample times?

I'm trying to deduce the white noise and rate random walk for an IMU. Some sources recommend deducing those values by fitting a line to the corresponding part of the log-log plot, and then reading the ...
0
votes
1answer
117 views

MPU6050 data go crazy while transmitting via HC-12 radio

I'm building a project based on the raspberry pi 3 (written in NodeJS & python) which uses the following modules: a bmp180 barometer, an mpu6050 imu, a hc-12 radio, a ublox-neo7m GPS, an LCD with ...
2
votes
1answer
225 views

Is IMU sensitivity always equal to FS / resolution?

I'm in the process of evaluating MEMS IMUs for a new design. According to this post, if a Gyroscope's range is ±250°/s, and its resolution is 16-bit (0-65535), then sensitivity can be calculated as: \...
0
votes
1answer
633 views

Drone gyroscope placement

I'm building a drone with an mpu6050. Does the placement of the mpu influence sensor data? I mean, if I rotate the sensor properly so that all axes point in proper directions, then will it matter if ...
1
vote
3answers
495 views

IMU Roll Angle - Correct when Stopped, Wrong when Moving

I have been using an MPU6050 (3 axis gyro, 3 axis accel, built in motion filter called DMP) on a car axle to measure axle angle when driving. On a long banked corner (2 degrees) the sensor reads 0 ...
0
votes
1answer
150 views

Raspberry PI, PCF8574AT, MPU6050, BMP180 i2c voltage difference?

I'm building a rpi 3 b+ based robot which collects data from a MPU6050 (Gy-521 breakout board, I power it with 5V), a BMP180 (3V input) and displays some data on a LCD via a PCF8574AT i2c converter (...
0
votes
1answer
536 views

What is sensor radius?

The manual for the bno 055 (link below) has an attribute for the sensor labelled radius on page 33. The radius takes up 2 bytes of memory, the msb and lsb. This already confuses me, as the msb ...
0
votes
0answers
497 views

What value pull up resistors does the MPU9250 use? [duplicate]

Looking at the datasheet On page 32, the datasheet says "The MPU-9250 always operates as a slave device when communicating to the system processor, which thus acts as the master. SDA and SCL lines ...
0
votes
1answer
117 views

Compensating for MEMS Gyroscopic drift

I'm new to IMUs and know that they are prone to high drift, which depends on Temperature, White Noise and Time, but the most uncertain drift is caused by time, and under certain circumstances, drift ...
-1
votes
1answer
1k views

refresh rate for gyroscop and accelerometer [ mpu6050 ]

What is refresh rate ( update rate) for gyroscop and accelerometer ? If you write in the register the following values in mpu6050 : SMPLRT_DIV --> 19 CONFIG --> 2 ( DLPF off )
1
vote
1answer
3k views

Converting MPU-6050's quaternion output to YPR angles

I am using the I2Cdev library which configures the MPU-6050 to use it's DMP and generate a quaternion output on it's FIFO. The problem is that when that quaternion number is converted to yaw, pitch ...
1
vote
2answers
1k views

Does multiple IMU increase accuracy

I'm just starting up with IMU's and I really want to work on my own flight controller, but a question always hits my mind and I am not able to find answer anywhere, so I'm here. Will multiple IMUs ...
0
votes
2answers
131 views

Angular Displacement

I'm working on a project in which I have to build a rover and remotely control it. Remotely controlling in the sense with basic forward and backward movement, as well as the right and left movement. ...
0
votes
3answers
970 views

What is the difference between cheap and expensive GPS receivers? [closed]

The cheapest class of GPS receivers is what we all have inside our smartphones etc. Then we have devices like this U-blox. In the end there are professional GPS like this SPAN combined with INS (IMU)...
1
vote
3answers
966 views

Quadcopter Balancing with PID algorithm

I am doing a project on self balancing quadcopter with Autonomous control. I am using Arduino Mega 2560 and MPU6050. I have obtained the roll and pitch angles from MPU6050 without the help of DMP and ...
4
votes
2answers
211 views

Is there a better filter or a modification to the Kalman filter that could take advantage of having all the data during the trajectory at once?

I am trying to reconstruct the trajectory of an object with an strapped down IMU on board to do dead reckoning. A Kalman filter seems to be in order. But the Kalman filter seems to be oriented toward ...
1
vote
4answers
284 views

Which is give better result for find angular position of device using 9-axis IMU snesor.?

I'm Using LSM9DSO 9 axis Sensor Which gives output of Accelerometer , gyroscope , Magnetometer Output data. i want to find the angular position of the device using this sensor. currently i'm trying ...
3
votes
1answer
3k views

How to calculate the orientation of a IMU sensor?

With a BLE CPro sensor I'm trying to "build" a remote control for a smartphone game. How can I recognise the orientation (pref. grads) of the sensor if it is on the left or right without being ...
2
votes
1answer
88 views

Recording heading with magnetometer that is inside spinning object

I'm wondering if it is possible to record the heading of an object (call it a ball) that has a 3 axis magnetometer in it? obviously if the ball was still it would be simple, but as the ball is ...