AutoQuad ver 5.6


The distributors finally got in some of the new ST Micro STM32F2 series uControllers and I grabbed a few.  I was able to "shoehorn" one into a ver5 board as the pinout is close to compatible with the performance STM32F1 series.  Spent a few days rewriting the device drivers and am very impressed with this controller's performance.

I was able to bump up the sample rate to around 276.8KHz for all 12 sensors for a total of ~3.32 million samples per second.  Despite this more than doubling of work load, I ended up with around 70% idle time, up from 60% of the STM32F1.  Keep in mind that at a 120MHz clock rate, this 70% free cycles represents more than twice as much free number crunching capability than the STM32F1 at 60% idle.  I also found that the DMA to be much better with full FIFO available on each DMA channel and an easier to use triple ADC.

The result is a much cleaner interpretation of the sensor data which translates to a smoother and more stable platform.

Take a look at this short demo of the STM32F215 in a hex frame:


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  • I looked at you scematics and I'm wondering why at the LD2985BM33R the Inhibit Pin is left openbecause in de datasheet it says that it has to be connected to Vin.
  • Wim: Turnigy hardware, modified firmware


    Patrick: I'll detail the V6 change in a new post once they are finalized

  • What will be the difference between V5 and V6?
  • Bill, were you using turnigy plush ESC for that hexa?
  • Bill all i need to no is where can i buy one of these good job  Tom
  • srinath: I try to avoid Matlab as it is slow.  All of my testing and filter code is done in straight C using libraries that I have developed over time.  If find that for maximum performance, a UKF needs to be properly tuned which can sometimes be difficult.  PM me for more info.


    Ludovico: Flight tests are conducted at a top secret testing facility somewhere in the eastern US :)  Actually it is an ideal place as it is slightly GPS deprived due to surrounding mountains and the wind is generally unpredictable - keeps you on your toes.

  • Awesome job, and BTW, were was this video taken? the landscape and free space looks awesome 0.0


  • Awesome job Bill

    I am interested in joining this project. I want to contribute to the state estimator design and improving the control law.
    I typically implement all the state-estimators as S-Functions in Simulink, before porting it on board. Is this how you do it? I currently have an EKF for ins-gps integration, my UKF seems to perform only on par with the EKF.
  • Patrick: V5 was 4 layers, V6 is looking like it will have to be 6 layers to get everything I want in it to fit.
  • Very impressive. I know for myself that it is hard to get a good GPS Performance. But yours is really good.

    I will try to build one of you boards. How many layers do you use.




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