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I am in need of a reliable gyro/accelerometer combo, that already has built-in motion processing (don't want to deal with Kalman filters in software). It seems that there are breakout boards out there (like IMU Fusion Board – ADXL345 & IMU3000), offering built-in motion processing, but the online comments sections reveal that that is not the case, or that it is rather hard to achieve. The MPU-6050 sounds more reliable, yet there is no official breakout board available yet.

The whole project will consist of ~25 sensors, that will all be connected to a desktop computer. I want to avoid having to do the heavy Kalman filtering for all sensors in software on the computer. Therefore i am looking for a sensor-board that already integrates the filtering.

  • DOF: I actually only need 1 DOF as the project has just one rotation point (think of a swing). But all available boards seem to have the maximum DOF.

  • Range: >= 150 degree/second

  • Frequency Response: >= 100 Hz

  • Noise: I am really hoping for a quite noise-free signal, to avoid heavy interpolation-filters later on (on the desktop computer)

  • A plus would be if i could daisy-chain those boards together. If not i'll have to add another hardware piece that chains them together.

Any recommendations or comments would be appreciated! Thanks!

EDIT: I found this MPU-6050 breakout board at drotek.fr, looking for some experience reports now.

EDIT2: I opted for the Razor IMU in the end, even though it was a bit pricey. There is pretty good firmware around.

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  • \$\begingroup\$ "MotionFusion" is apparently Invensense's name for integrated kalman filtering. As such, it's not a general term in really any sense. I changed your title to reflect this. \$\endgroup\$
    – Connor Wolf
    Commented Feb 2, 2012 at 4:39
  • \$\begingroup\$ Incidentally, this is kind of a shopping question, which is generally frowned on. However, there are enough non-shopping avenues of inquiry that I'm leaving it as-is. \$\endgroup\$
    – Connor Wolf
    Commented Feb 2, 2012 at 4:42
  • \$\begingroup\$ Incidentally, have you looked at the SparkFun Razor IMU? It seems like it can do what you want, and the software has apparently been updated to work with the last few months. \$\endgroup\$
    – Connor Wolf
    Commented Feb 2, 2012 at 4:44
  • \$\begingroup\$ thanks for correcting. and yes, it is inherently about shopping, but it would avoid lots of extra how-to questions later on (if i buy the wrong thing) :) Looking at the Razor IMU now. Looks interesting. Maybe a bit above the wished price-range (considering i'll need 25 of them). \$\endgroup\$
    – evsc
    Commented Feb 2, 2012 at 16:16
  • \$\begingroup\$ Please add some specs such as the accuracy needed, the frequency response, the maximum computing load that you can have... \$\endgroup\$
    – clabacchio
    Commented Feb 2, 2012 at 16:18

2 Answers 2

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I've worked on a project to implement the Kalman filter on an embedded system that was similar in hardware to the iNemo unit from STMicroelectronics.

Even if you can find these IMU (Inertial Measuring Unit) with 90% chance you will have to implement your algorithm by yourself; or if you're lucky, you can find someone that has the code. The problem is that this filter requires a lot of computation, and in our best experiment (using fixed point variables and trying to optimize the code) we were able to run it 45 times per second, in a STM32 at 72 MHz.

So maybe there is one, but as far as I know requires a good microcontroller or maybe a FPGA\ASIC.

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  • \$\begingroup\$ Thanks for the insight. Our project would probably work at 45Hz. But we don't have the time to create our own system, so i am hoping to find a rather simple plug+play solution. \$\endgroup\$
    – evsc
    Commented Feb 2, 2012 at 16:23
  • \$\begingroup\$ I've seen that OpenCV has a library function for Kalman filter but I think that is quite dependent from the application, so good luck to find one :) \$\endgroup\$
    – clabacchio
    Commented Feb 2, 2012 at 16:29
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Use a Wiimote with the motion plus accessory.

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  • \$\begingroup\$ How does this help? \$\endgroup\$
    – Brian Carlton
    Commented Sep 21, 2012 at 16:31
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    \$\begingroup\$ A Wiimote is a device which includes a IMU. And you can connect to it using bluetooth. \$\endgroup\$
    – Blup1980
    Commented Sep 21, 2012 at 17:13
  • \$\begingroup\$ What ?? It solved the problem...... It's an integrated, off the shelf solution and protocol is well known. \$\endgroup\$
    – Blup1980
    Commented Sep 21, 2012 at 17:25
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    \$\begingroup\$ @Blup1980I think you would get a better response if you were to add more detail. What specs does the WiiMote meet, what are its real specs. \$\endgroup\$
    – Kortuk
    Commented Sep 21, 2012 at 17:42

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