(Open source avionics: Last updated by Benjamin on August 28, 2024)
What is avionics?
Avionics includes all an aircraft’s electronic and computer systems, from radio communication devices to engine monitoring systems. It also includes navigation systems, autopilot, anti-collision systems, flight parameters monitoring, sensor and actuator management, etc.
In certified aircraft, all these systems are TSO’ed, designed, installed, and maintained by authorized professionals.
The regulations are more flexible for homebuilt, experimental, and ultralight aircraft. One of the basic rules is the individual responsibility of the owner and the pilot. In no way is the latter exempted from the obligation to respect the rules of art and airworthiness monitoring. The owner/pilot is responsible for maintenance and continuing airworthiness and may thus intervene in most avionics systems. However, systems that possibly affect the safety of controlled airspace may remain monitored by the authorities (VHF and transponder, for example).
Who is this open-source avionics website for?
This site is intended for all owners, pilots, and amateur builders of non-certified aircraft. Especially those who are passionate about electronics and computer sciences. For those who wish to know more and share about open source avionics systems. For those who dream about designing, building, programming, installing, and operating their own devices: EFIS, EMS, and more. Under their responsibility. The only prerequisite is to have a soldering iron!
How is it possible?
This challenge was made possible thanks to the advent of high-performance microcontrollers that are easy for enthusiasts to master. Therefore, the only limit is passion! The Arduino project dates back to 2005 and made the world of microcontrollers easily accessible to non-professionals. At an insignificant cost, it allows complex developments and efficient devices combining sensors and actuators. Such as a robot, a home automation station, or… an artificial horizon!
We will see (here) that Arduino boards are not the only ones on the market nor the most adapted to avionics needs. Nevertheless, their fame and their anteriority justified the domain name of this site: avionicsduino.
Website goals
The primary purpose of this site is to present the circuits and software for avionics systems that meet these specifications:
- Anyone can build and program them, starting from elementary basics.
- They are economical; their price must be much lower than that of equivalent commercial systems.
- These systems genuinely work; they have been flight-tested.
This Website also aims to present more general articles on microcontrollers, tests, techniques, projects in progress, etc., always in the field of avionics and aviation.
The concept of open-source avionics makes it possible to build highly personalized, high-performance systems that are much more economical than certified ones while learning a lot and having fun! The aircraft airworthiness manager ensures its achievements do not compromise safety or contravene regulations. French regulations can be consulted here. US and UK regulations are not so different for uncertified ultralight, homebuilt, or experimental aircraft. A manufacturer’s authorization may be required to modify its equipment for Light Sport aircraft.
It is necessary to keep in mind that these systems are to be produced yourself; they should not be used during flight as if they were certified; their builder must extensively test them to evaluate their performance; they must always be used in addition to the mandatory instruments; they must not lead to a significant modification of the aircraft which could require approval from the authorities. There is no guarantee of the accuracy and reliability of these systems other than that evaluated by the builder under his responsibility. Of course, IMC, IFR, and night VFR are excluded! Only daytime VFR, where the failure of these systems does not compromise safety, thanks to appropriate backup instruments.
This site’s information, software, and hardware are subject to a disclaimer and a copyright notice.
Authors
The authors are neither aeronautical professionals nor electronics or software engineers. They are amateur builders of their planes (three MCR Sportster) and are driven by the same passion for electronics and computers.
Mr. Benjamin:
Thank you. Then we can use a portion of your code.
The 2.1-inch and 3.5-inch EFIS are made by ourselves, and they lack the functions of inertial attitude calibration and airspeed indicator. We have only added this part to the 4.2-inch model we are currently working on. We are currently producing a 4-inch square screen EFIS
About openvario, I am builder 94, and my friend is buider83. He often posts updates on Facebook. However, due to the development of aircraft sensors, he has recently encountered difficulties. In order to develop funds for us, his house was taken away by the bank.
Hello Tingyun,
Thank you for your comment.
Everything on the AvionicsDuino website is Open source software and hardware.
The software on GitHub is licensed under the MIT license: you can copy, modify or even sell it, but if you distribute the source code (in whole, or substantial portions of the Software), it must include the original MIT license with the AvionicsDuino name.
The hardware is licensed under the CERN-OHL-W license. You cannot modify or distribute the design files by removing the “AvionicsDuino.com” brand and logo or by replacing them with your own brand/logo. You can sell printed circuit boards, but they must include the AvionicsDuino brand and logo.
I have added a “Disclaimer and Copyright” page to the website.
We would be very happy if you would agree to share your possible modifications and improvements on the AvionicsDuino website. Your name and organization will obviously be cited. Also keep us informed if you develop a commercial version of our achievements.
I did not see your name in the contributors list of the openvario project. This project actually seems abandoned? What is your current organization?
Concerning the AHRS, a reader of the site has developed a version based on an ESP32, actually cheaper than the Teensy 4.0 board.
Benjamin
Mr. Benjamin:
We are developing EFIS, EMS, and turbine monitoring equipment.
We were originally involved in the builded of openvario.
We have studied the BOM list of your EFIS
We think the total price of the materials is about $250.
If a good aluminum alloy shell (CNC process) is added, the cost will be even higher.
Plus the production cost, it will cost around $350
We suggest that you replace the main control chip of arhs. For example, ESP32
We also borrowed your interface during development.
Therefore, someone wants me to copy your work. (Because your system also includes EMS)
I’m not sure if this is possible, so I’m here to inquire with you.
If there is infringement, I will refuse them.
Hi Mauricio,
Thank you for your kind comments.
I know the Gazaile 2 very well. It shares many aerodynamic similarities with the MCR Sportster (which derives from the Bambi).
If you are embarking on this experience of building your avionics, feel free to post any comments if you encounter any problems.
Benjamin
Good morning!!, I am glad to have found your page!, I am going to investigate all the details, my name is Mauricio Reynoso, I am from Argentina and I am almost finishing an airplane very similar to yours, it is a Gazaile 2 and I am always eager to manufacture an instrument, so your project is just what I need, I loved it!!
Thank you very much and we are in contact
Gazaile Mauri
Hello Tomas,
Thank you very much for your kind comment.
We are delighted that the AvionicsDuino website has been helpful to your studies and projects.
Congratulations on your flight data recorder project! We would be pleased if you shared a link to this project.
Indeed, you may have seen the page on our site about our single-board computer-based flight data recorder. This recorder is not ergonomic, and we are currently testing a new one based on an ESP32 board. It records all the data exchanged over the CAN Bus on a micro SD card. The files on the SD card are retrieved on a smartphone via WiFi at the end of the flight. When it is finalized, it will be published on the site.
We would be very grateful if you could cite the AvionicsDuino website as a reference for your research work.
All the best to you,
Benjamin
Hello!
Firstly, I wanted to express my gratitude for your work. As an undergraduate student, your project has been an invaluable stepping stone for me, particularly in developing a more complex sensor system. Your tutorials and the information provided, along with the components from your AHRS project, have greatly assisted me. Thank you for your impressive contributions.
Secondly, I’m currently developing a project that, while distinct from an EFIS system, is a flight data recorder for UAVs, integrating multiple variables and sensors apart from the a GPS and IMU. I’ve utilized your resources extensively in this endeavor. As I prepare to present this project at a student conference, I want to ensure that you receive appropriate recognition for your contributions. Could you please inform me how you would like to be cited or recognized? Whether it’s by specific names or as an organization, I want to respect your preferences.
Please let me know your thoughts on this.
Best wishes.
Hello Albrecht,
MPU9250 is no longer being manufactured or sold by InvenSense. It is increasingly difficult to find. Online sales sites are full of non-functioning clones of dubious provenance. For our AHRS, we prefer to use more modern and efficient STMicroelectronics sensors that are very easy to find on the market: the LSM6DSOX (triaxial accelerometer and triaxial gyrometer) and the LIS3MDL (triaxial magnetometer). I am not familiar with BNO055.
We would be glad if the AvionicsDuino site could help you design and make your own instruments for the ULF2.
Benjamin
Benjamin, thank you for your reply. Our MPU 9250, bought recently, behave different from our older versions. We are not able to connect to the magnetometer, what is not a problem with an older one.
And it is not a single defective device. Any of our five new MPU9250 s behave in the same way.
May be, the bno055 is not made for fixed wing AHRS application. But our tests did not even give reproducable results in stationary operation. The self-calibration destroys after a short time any initial calibration state and this cannot be switched off.
By the way, your MCR is a very beautiful aircraft! I flew a FK9 until some years ago. And today a homebuilt ULF2, single seated motor glider, powered with an old Citroen Visa engine. I am just interested in Avionics and Arduino solutions, not necesserily essential for this type of aircraft, of course.
For the ULF2, that has very limited space on the dashboard, I have made a digital oil-pressure gauge and digital tank indicator, as well as a vertical speed indicator.
A combined compass and attitude indicator would of course be nice, as well as a non drifting barometric altitude display, with the possibility to key in a QNH. I also had made some experiments with differential pressure gauges for an arduino based airspeed instrument, but the sensor for this low speed area was almost more sensible to gravity field changes than pressure difference…
So I am glad to find your website and will shurely find interesting solutions, that we can gradually adapt for our aircraft.
Albrecht
Thank you, Albrecht, for your kind comment.
BNO055 and MPU9250 are neither catastrophic nor defective. They were just not designed to constitute an AHRS for a fixed-wing aircraft on their own.
I hope you find helpful information on this site for your projects.
Benjamin
Benjamin,
a very interesting website! I am working (as a hobbyist) on a similar theme. Had a RC-flight controller, Pixhawk) abused to make something similar to an attitude indicator some years ago.
Now we are trying to build such a device on our own, based on NDOF sensors, but up to now with very little success. The BBO055 is absolutely catastrophic, and the MPU 9250, sold today, are obviously defective…
So we would like to adapt your open source project, in order not to invent the wheel again and again…
Any of your solutions and experience are welcome, and we would like to get in e-mail contact with you.
Best regards
Albrecht
Hello Stefano,
I will send you a private email.
Benjamin
Ciao, I’m building a similar system, like a glass cockpit integrated with Navigation.
I have screenshots and other resources ready.
I like your schemes, I would like to integrate your EMS.
I have long time experience on remote displays, tablets, android, iOS, Bluetooth, WiFi, ect…
Can we exchange contacts?