Hello everyone, I don’t know if it is right to post my question here. Hope it won’t violate rules of this forum.
Currently two of my friends and me are designing a HAT of Raspberry Pi 2. Kind of in the early stage though.
Since we have played with APM around for quite a while, it is so attractive and gave us tons of fun 
. Thanks very much to the authors and all the contributors for creating such a great project.
Now we are trying to enable APM on this HAT with RPI2. Some of the HAL code based on Copter-3.3 branch have been implemented and under testing. I just want to know is it possible we can merge our code to your upstream.
We call our new HAT “BH”, it contains various sensors, together with RPI2, they can do similar things like the BBB board, even more 
Here is a simple list of HW and SW features:
BH0.1 HAT:
- MPU6050
- HMC5883L
- MS5611
- PCA9685
- ADS1115
- DS1339
- NEO UBLOX M8N
- Several leds
- I2C/SPI/UART extension ports
SW on RPI2:
- Debian jessie armhf user land
- Linux 4.1.9 + preempt-rt-4.1.7
- Copter-3.3 release
- Many other pre-installed packages
Maybe MPU6050 and HMC5883L will be replaced by MPU9250 in future
We would like to introduce BH HAT to the APM and RPI community, because we believe that Linux + APM will bring our fun to a whole new level, it just can’t wait 