Hey guys!
We made a small demo of IMU with NAVIO to show real-time performance of the platform. The algorithm is Mahony quaternion based. The sensor is MPU9150 connected over I2C.
The IMU runs well over thousand of Hertz and takes around 20 percent of CPU. When running on typical for autopilots 200Hz update rate the load falls down to 4-5%, and when pumped up to 3000Hz takes almost 50%.
Raspberry Pi is able to perform other tasks while running an IMU, in the video we demonstrate that such heavy tasks as compilation do not affect the rate of the real-time IMU.
Also, there’s a PWM controller working simultaneously on the same bus, which can be seen by the LED changing colors.
In the final version of Navio we are using MPU9250 that is connected over SPI and can be polled at the full gyro update rate.
For more information about the project please visit our blog at emlid.com
Comments
Mike,
Brownouts happen when too much current is drawn by Raspberry Pi peripherals like usb hubs etc. Navio is powered separately and is equipped with LDO. In autopilot application power to raspberry should be supplied by separate BEC trough a standard header on Navio.
I have tinkered with the Pi enough to know that the power filtering on the board is not that good and it is easily subject to brownouts. I would have a VERY hard time trusting this an autopilot...
or am I way off base here?
Hi Gary,
Thank you!
The project is open source, and we are currently working on porting APM to the platform.
The board will be available for preorders mid May for 165$.
Hi Emlid,
Looks like a great project,
I looked but couldn't find - Is this open source - open hardware?
What is state of integration with autopilot functionality?
How soon?
How much?
Best Regards,
Gary