As we prepare to migrate our current LabVIEW groundstation from ArduPilot to supporting ArduPilot Mega, we're taking the opportunity to rethink its architecture and code base.
Right now it's written in LabVIEW, a visual programming environment that has the advantage of rapid development and easy-to-make instrument displays, as well as being cross-platform. But the problem with it is that the development tools aren't free (indeed, the ones that can create an executable file start at $1,249!), and distributing the files requires users to download a runtime engine and serial driver. As a result, we don't have as much community participation in the ground station as we do in most of our other projects.
Over the past year, we've been looking for an alternative with free and good development tools. It needs to be cross-platform, compatible with open source code standards, and appropriate for a ground station (ie, able to handle a rich visual environment and to talk directly with the serial port). Eventually a good candidate emerged in Nokia's Qt application and UI framework, and I'd like to present it here for community feedback.
You can see a glimpse of Qt above, but here's the description from the site:
"Qt is a cross-platform application and UI framework. Using Qt, you can write web-enabled applications once and deploy them across desktop, mobile and embedded operating systems without rewriting the source code.
Features
- Intuitive C++ class library
- Portability across desktop and embedded operating systems
- Integrated development tools with cross-platform IDE
- High runtime performance and small footprint on embedded"
Note that it's cross platform on more than just computers--it will also run on phones, too, which introduces the possibility of an ArduPilot GCS on Android or some other smartphone, which would be very cool. Also, we intend to integrate the current ArduPilot configuration utility into the GCS, so one desktop program can handle all the ArduPilot functions, from mission planning to real-time data display, including integrated Google Earth and video handling and image processing.
So what do you think? Is this a good code foundation for a full-featured groundstation? Does Qt look like something you'd adopt for the right project?
[UPDATE: See this Swiss team's MAV groundstation for an example of what Qt can do. Nice! It's open source, so we can build on it if we want.]
Comments
That looks like an amazing project, very very powerful hardware and their Quad is so stable.
Anybody know anything about the PixHawk MAV project?
I strongly disagree with this, additionally Qt is not as they advertise "write once, run anywhere". Python is much more cross platform than Qt in C++ by a long way.
With nearly 10,000 members, I'm pretty sure we can find a few C++ developers in this community. With Howard's comments in mind about the cross-platform limitation of Python, I'm tempted to just do it right.
For Ardu I personally do not think Qt & C++ fits very well, I would seriously consider Python with Qt bindings. It gets what you want without needing C++ developers, Python seems to fit with the project a lot better and there is a higher learning curve with C++, it just doesn't feel like it is a fit for Ardu as well as Python does.
Obviously as a lot of people know OpenPilot is using Qt for our GCS and this is where Chris learnt about it, we are taking our time with OpenPilot hence C++ was chosen as it is what I know being a KDE developer. We would have got many more developers if we had used Python or Java for sure.
We also have a OpenPIlot GCS running on Android (or at least I do as this is my project) but again Qt is not the right tool for this, Java is on Android.
I do think Processing is an interesting choice, but just don't know how easy it is to create a full UI with it.
Python could could work with a Flash front end, but would required running two programs, not one, I think. I think Jason would be the best to comment on that, since he's done something similar with his GCS.