Featured with high speed ARM Cortex-M0 based processor
Intelligent power management system, comes assembled and tested
The BNO055 9 DOF Absolute Orientation IMU Fusion Breakout Board solves the issue of orientation by taking help of a MEMS accelerometer, magnetometer and gyroscope and putting them on a single die with a high speed ARM Cortex-M0 based processor to digest all the sensor data, abstract the sensor fusion and real time requirements away, and spit out data you can use in quaternions, Euler angles or vectors.
It can output the following sensor data:
Absolute orientation (Euler Vector, 100Hz) Three axis orientation data based on a 360° sphere
Absolute orientation (Quaterion, 100Hz) Four point quaternion output for more accurate data manipulation
Angular velocity vector (20Hz) Three axis of 'rotation speed' in rad/s
Acceleration vector (100Hz) Three axis of acceleration (gravity + linear motion) in m/s^2
Magnetic field strength vector (100Hz) Three axis of magnetic field sensing in micro Tesla (uT)
Linear acceleration vector (100Hz) Three axis of linear acceleration data (acceleration minus gravity) in m/s^2
Gravity vector (100Hz) Three axis of gravitational acceleration (minus any movement) in m/s^2
Temperature (1Hz) Ambient temperature in degrees celsius
I didn't think it was possible to reliably sort out the absolute orientation from this kind of sensor data, but somehow these guys have managed it. I'm using two of these for the wrist rotation of a wired glove. Both attached to the forearm, one toward the elbow and the other toward the wrist. Inverse transform the wrist by the elbow, and you get a quaternion that only changes with wrist rotation, and not with arm/body movement. I was worried they might be too wishy washy for it to work, but from initial tests with them taped to my arm, the resulting wrist angle seems to be quite stable. Amazing! A few tips: 1. Give it a few ms to boot up before you try to communicate with it. I'm using a bare ATMega168 (same family of microcontroller as Arduino), and the TWI hardware makes communication very simple with just a few register reads and writes, but there's no indication that the sensor is present until it finishes booting up. 2. Make sure it gets itself fully calibrated. The calibration process runs continuously while in NDOF mode, but you need to do a certain series of movements for it to work (explained in the manual). 3. Be sure to treat the values it returns as signed 16 bit rather than unsigned (d'oh!)
S
Sonny
Really accurate
I'm very surprise of the accuracy of this little module!
S
Sonny
Vraiment précis
Je suis très surpris de la précision de ce petit module!
R
Robert
Fun to play with but actually not useable as a real compass
I didn't have much success with this product. I tried to build an electronic compass for my little yacht. It was OK when the boat was stationary but as soon as the boat started to move I found that the built-in self calibration process made the compass readings very unstable and innacurate. So product is not useable for my application.