More News about GRCon17

Tom Rondeau

I mentioned in my last post, the DARPA Bay Area SDR Hackfest will have a solid presence at GRCon in San Diego next week. I’ll be giving a talk about the Hackfest, and we will be holding a workshop on Thursday afternoon to discuss more details of the hardware and software that the Hackfest Missions are centered around. I have posted the abstract for my talk below, but I wanted this post to focus on the workshop.

At the workshop, we will spend time on both the Missions and the Hacker Space, another element of the overall Hackfest. The plan is for the DARPA’s Hackfest organizers to present the drone and SDR hardware along with the software we’re bringing to the Hackfest for the Mission teams. The hardware is pretty well advertised and known to most of this community. We’re using a 3DR Solo drone that uses a PixHawk-2 flight controller, and we’re mounting a Raspberry Pi 3 and a USRP B200mini onto it as the embedded computer and software radio. We are still working with NASA Ames on spectrum coordination, but once that’s settled, we will also be getting amplifiers and antennas to suit the frequencies we will be using.

The software is the more interesting piece of the solution to discuss. While the Mission teams are tasked with building software to solve the Mission problems, we wanted to present a simple working solution to flying a drone via software radio. Maintaining a two-way connection and passing packets, including keep-alive packets required by MAVLink, is not trivial but also not particularly exciting. Getting all teams up to speed on just this concept allows everyone to a) play with the software and basic tools for a couple of months before the Hackfest and b) make sure that all the teams can be active immediately once they start their work. We will be eager to see how teams build upon this software foundation.

At the workshop, we will review the software and how it integrates with other open source code for MAVLink packet manipulation as well as how to use it within a simulation. By the end of the workshop, we hope that everyone who comes is able to download and install this software, known as gr-uaslink, and be able to control a drone running in a simulator on their computer. DARPA organizers will then complete the loop and prove the concept by demonstrating the use this same software to control a real drone to. We are hoping everyone can walk away from this workshop with a working simulation and knowledge of the steps they need to take towards controlling their own drone through a software radio.

The workshop is not just for the Mission teams, either. We are hoping others find this technology concept interesting enough to want to learn about it and participate. I suspect this could lead to other great insights and innovations outside of the Hackfest’s Missions and provide people coming to the Hacker Space with interesting things to work on.

While the workshop is for everyone and not just the Mission teams, I am excited that all (or almost all) of the eight selected teams will be sending at least one representative to GRCon17 and will be participating locally in the workshop. This is a great opportunity for the teams and the community to get to know everyone involved.

I am excited to say that the code we are developing will be released as open source and that we are working with the Defense Digital Services team to have them host the code on

Finally, an important aspect of this hackfest is the Hacker Space. As such, at the GRCon17 workshop, I want to brainstorm on some good questions and topics for attendees to pursue.

Here is the abstract of my GRCon17 talk (Thursday, Sept. 14 at 9:30am):

Hackfests are a way of engaging a community to rapidly respond to and solve technical problems. Hackfests are short, on the order of days to a week, but this tightly focused structure allows for bursts of creativity and development. GNU Radio has made great use of hackfests for many years where a group of the core developers come together for 3, 4, or 5 days to work on serious bugs and features for the project. DAPRA is looking to build on that type of success. Whereas GNU Radio hackfests have traditionally focused on directly developing for GNU Radio, the DARPA Bay Area SDR Hackfest will explore how to better utilize software defined radio (SDR) to solve interesting problems.

The DARPA Bay Area SDR Hackfest, which will be held from November 13-17 at NASA Ames in Mountain View, CA, challenges attendees to think about new applications of unmanned aerial vehicles (UAVs) once we modify these so that they can serve as programmable extensions of a computer. To accomplish this, we are putting an SDR onto a UAV, thereby converting the vehicle into a radio link between the ground station and the flight controller. We will use GNU Radio to define the physical RF link to transmit protocol packets to the onboard PixHawk-2 flight controller. This concept presents an exciting opportunity for teams to develop new application spaces and capabilities for UAVs. While the team-oriented event, known as the Hackfest Missions, is going on throughout the week, we will also have an open Hacker Space and Speaker Series available to the public to attend, hack, and meet and engage with the rest of the community. This talk will discuss the specifics of the DARPA Bay Area SDR Hackfest, how all of the events work together, and how the open source community can get involved. The software radio-enabled drone will also be demonstrated along with a deeper dive into the hardware and software we are putting together to support the work at the DARPA Bay Area SDR Hackfest.

More information on the DARPA Bay Area SDR Hackfest can be found at