Let’s Talk About Stress…. (or The Trials of Flight Trials)

Picture this. You and one colleague are over 1,000km from the office and seven hours into a two day flight trial. It’s 35 degrees in the shade, you've just been stung by a wasp, and you have a problem. Something to do with your integration tests is not working. You are running out of ways to debug the problem. Stressed?

The answer could very well be yes, particularly when we throw into the mix that this is the very first flight trial of this software. Everyone back at the office is very excited about showcasing a success story at DroneX Tradeshow & Conference .

Before we give you our engineers’ perspective, let’s take a look at the software we were testing.

ACAS sXu is an Airborne Collision Avoidance System for small un-crewed aircraft systems. This Detect-And-Avoid (DAA) system is recognised as critical to enabling beyond visual line of sight operations (BVLOS). Earlier this year we posted here about the potential of the un-crewed aircraft market and we’ve shared the Satellite Applications Catapult podcast where our colleague Dr Anthony Lawrenson talked about the potential applications of these technologies here.

Drone operators are beginning to commercialise a wider service offer and we expect demand for applications requiring BVLOS to accelerate.

The ACAS sXu specification has been developed by a partnership of representatives from industry, university and regulatory bodies and is published by the RTCA. At Volant Autonomy we are developing a certifiable implementation of this specification. Integration of this software into a small un-crewed aircraft will provide the requisite mitigation for DAA during BVLOS operations. The system allows our users to engage in more complex flight operations in multiple airspace classes.

It feels like we just turned up the pressure another notch!

The flight trial took place at BCN Drone Center , a fantastic facility for un-crewed platform testing. For the trials, BCN Drone Center supplied us with a quad-plane into which our DAA system was integrated. To power this early stage integration testing we are utilising a Jetson Xavier-NX, chosen for the balance between form factor and processing power. Through collaboration with BCN, we utilised a plug-and-play approach to provisioning and integrating our software with their system.

The test plan for the flight trial devised a number of test scenarios, each building on the previous to ensure that every element of the system was working as expected. Step-by-step, from turning ACAS on to receiving communications from the autopilot, communicating to our bespoke Ground Control System to sending instructions to the autopilot, we checked behaviour matched expectations.

With all this at stake, the carefully laid, pre-tested plan going awry, and the clock ticking, would our Volant Autonomy engineers Alex P. and Daniel Holmes crack under the pressure?

In their words “flight trial success was never in any doubt”.

And the difference between giving into the stressful situation or pulling out a five-star performance? Pre-trial contingency preparations and the team, over 1,000km away back at the office, providing support, suggestions and debugging the setup remotely.

The problem was caused by a minor variation in the specification of the autopilot system in use. A hardware issue was stopping communication between our computer and the aircraft's autopilot. Luckily we had come prepared and had already tested alternate communication methods at the office. Once they had diagnosed the problem, our team managed to quickly and safely change communication methods and finish the integration with time left to fly. We got the data we needed and the results we expected from the software’s performance. A significant milestone passed in our development of ACAS sXu.

The next steps for ACAS sXu are another flight trial in two weeks’ time, focusing on testing functionality - our engineers will be heading back to BCN with another comprehensive test plan and a (slightly longer) debugging-in-the-field checklist.

To find out more get in touch, visit us at?www.volantautonomy.com?or come and see us at DroneX, exhibition stand D103 - you may even meet the heroes of our story.

#aviation #flighttrials #drones #engineering #acas #stressednotstressed