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Author Topic: 9 DOF Razor help  (Read 900 times)
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Hi, I'm a newbie and am a little stuck. I have just purchased a 9 DOF Razor IMU (SEN-09623) and a 3.3v FDTI breakout  (DEV-08772) which I'm powering via usb.

I'm trying to convert the gyro reading to angles but am doing something wrong. If i turn the board 90 degrees my conversion will only give me readings of around 30 degrees.

Here is my algorithm

sensitivity = 0.83 // as per datasheet
zeroLevel = 1.23 // as per datasheet

degPerSecond = (gyroXvalue * 3.3/1024 - zeroLevel)/sensitivity

angle = degPerSecond * elapsedTime + previousAngle


I'm using the values of 3.3 because its a 3.3V power supply and 1024 because its a 10 bit ADC

What am i doing wrong? Do i have the sensitivity and zero level correct? I would like post the datasheet, but not allowed.

Any guidance would be really appreciated.

Cheers
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Now you've made one post you'll be allowed to post a link to the data sheet.

Andrew
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The 9DOF razor
http://www.sparkfun.com/commerce/product_info.php?products_id=9623
 has two gyro's. A LY530AL (single-axis gyro) and a LPR530AL (dual-axis gyro).

Here are the links to the datasheets

LY530AL:
http://www.sparkfun.com/datasheets/Sensors/IMU/LY530ALH.pdf

LPR530AL:
http://www.sparkfun.com/datasheets/Sensors/IMU/lpr530al.pdf
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I don't think you connected the grounds, Dave.
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What is your analogue reference voltage?
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Not too sure. How do i find out the analogue reference voltage? It's powered via USB if thats any help.

Sorry, im new to this
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hi, i'd purchased the same type of 9 dof as you are and connected it to my pc via Ftdi basic . Could u give me the code in adruino software, to display the value of gyroscope, accelerometer and magnetometer? thank you an advance.
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