Intro

A week ago I worked on the project which aim was to build a drone from ordered accessories and write own or flash existing firmware. It was not a project for a potential customer, but research's milestone results and gained expertise might be interesting for my readers.

Discovery

It was a new domain for me and, at the first, the project required a R&D phase. At the discovery phase we have to answer a set of questions necessary to the success of the project. This questions had been stated in the online document and the tech doc had been shared with the group. When key questions had been answered, a picture of what should be done became more or less clear. The next step should be to launch a pilot project to check the result of the research.

Solution

Firmware

Market analysis shown a variety of different existing solutions. The most promising was the Ardupilot.

Ardupilot supports a quite big set of hardware suppliers, may be they even have some kind of partnership agreement. In case project would have new requirements to the hardware which outscope officially supported by the Ardupilot, existing Ardupilot codebase could be a good starting point to make a fork and write our own customised firmware version.

The market also has other systems and solutions. Of course, it is also possible to write our drone's firmware from scratch, but it will require an order of magnitude more resources, that's why to check existing solutions at first is important.

Hardware

The most important part of drone hardware is a pilot controller. Ardupilot supports many models, but at this stage CUBE orange was checked
Reference on the sample at the aliexpress.

On the image below the rest of drone's components are shown (CUBE compatible, one of the options)

The problem of compatibility of the flight controller and the Remote Controll (radio transmitter directly in the hands)

Research phase revealed RC usually developed for specific drone and supplied by manufacturer. There is a cross-compatibility issue. However, the main problem is in the frequency and protocol used. According to the discussions, multi-protocol controllers are compatible with a large number of flight controllers / drones.

Althought top drone's models on the market has extra layers of security to prevent hijacking and some other issues.

This issue requires extra research, but at this stage we could go further with multi-protocol support radio controller like TX16S Hall Radio Controller

Post Scriptum

Research phase helped to rised up and clarified questions to build a drone. The next pilot phase should help to verify assumptions and come to production ready solution. At this moment the further work has been hold on due the decisions to go at first by the different way. The current tech doc is avaialble by link.