Axis Orientation problem (visual) when rotating with the 9DoF Razor IMU M0

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1

I bought the 9DoF Razor IMU chip and connected to a 3D printed solid model and then connected it to the computer using p5 serial control, and then tried to run a code with Processing software

Hypothetically, if I rotate the model, it should show a similar rotation pattern after I run the code, but when I try to do that, there is a problem with the orientation, it is inverted.

https://media.discordapp.net/attachment … height=601

The code for this is:

var serial;

var shape;

var rot=[0,0,0];

var logString=“Waiting”;

function preload() {

shape = loadModel(‘data/BIG_TURBO.obj’);

}

function setup() {

createCanvas(400,400, WEBGL);

serial = new p5.SerialPort();

var portlist = serial.list();

serial.open(“COM10”,{ baudrate: 115200});

serial.on(‘open’, gotOpen);

serial.on(‘data’, gotData);

serial.on(‘error’, serialError);

textSize(15);

xSlide=createSlider(-3.14,3.14,0,0.03);

ySlide=createSlider(-3.14,3.14,0,0.03);

zSlide=createSlider(-3.14,3.14,0,0.03);

}

function draw() {

background(255);

ambientLight(255, 0, 255);

directionalLight(255, 255, 255, 0, 0, 1);

//noStroke();

rotateX(rot[0]+xSlide.value());

rotateY(rot[1]+ySlide.value());

rotateZ(rot[2]+zSlide.value());

scale(30);

model(shape);

}

function gotData() {

var conv=3.14159/180;

var currentString = serial.readStringUntil(“\r\n”);

print(currentString);

var itemized=currentString.split(", ");

if(itemized.length>1){

rot=[itemized[10]*conv, itemized[11]*conv, itemized[12]*conv];

//print(itemized);

}

}

function keyPressed() {

if(key=“r”){

print(“Reseting sensor rotation”);

xSlide.value((xSlide.value()-rot[0]+3.14)%6.28-3.14);

ySlide.value((ySlide.value()-rot[0]+3.14)%6.28-3.14);

zSlide.value((zSlide.value()-rot[0]+3.14)%6.28-3.14);

//xslide.value(0);

//yslide.value(0);

//zslide.value(0);

}

}

function serialError(err){

print(err);

}

function gotOpen(){

print(“OPEN”);

}

When i try to rotate it, the visual rotates in total wrong direction. Please help to fix this orientation problem thank you!

2

Hi ahmf239,

It looks like the values your code is expecting are inverted from the orientation of the sensor. Your photo shows the Razor IMU “upside-down” in your model. You should be able to fix this by inverting the values sent by the IMU. Section 9.1 of the [MPU-9250 Datasheet gives a good view of the orientation of the three sensors inside the IMU.

If that does not resolve the issue, it may be something with your code and, unfortunately, we cannot help you debug custom code. Hopefully, it’s just a matter of orientation and the values your code is expecting.](https://cdn.sparkfun.com/assets/learn_tutorials/5/5/0/MPU9250REV1.0.pdf)