Håkan Forsberg

Luiz Giacomossi, Andrea Haglund, Claire Namatovu et al.

Reliable autonomous UAV swarms in Search and Rescue (SAR) missions require fault-tolerant coordination capable of sustaining operations despite agent degradation. This paper introduces the Intelligent Replanning Drone Swarm (IRDS), a distributed coordination architecture designed for resource-constrained environments. The proposed framework employs a Reverse-Auction market mechanism where agents bid to service search sectors based on a distance-weighted cost function, coupled with a geometric consensus protocol for target verification. We evaluate the approach through physics-based simulations (N=8 agents, 8x8 grid) subjected to stochastic fault injection. Results indicate that the swarm autonomously reallocates tasks from failed agents with low latency relative to the total mission duration, maintaining a mission success rate of 93% under 25% workforce degradation. The proposed framework demonstrates a robust, empirically tested method for self-healing aerial robotic coordination.

Luiz Giacomossi, Håkan Forsberg, Ivan Tomasic et al.

Modern UAV architectures increasingly aim to unify high-level autonomy and low-level flight control on a single General-Purpose Operating System (GPOS). However, complex multi-core System-on-Chips (SoCs) introduce significant timing indeterminism due to shared resource contention. This paper performs an architectural analysis of the PREEMPT RT Linux kernel on a Raspberry Pi 5, specifically isolating the impact of kernel activation paths (deferred execution SoftIRQs versus real-time direct activation) on a 250 Hz control loop. Results show that under heavy stress, the standard kernel is unsuitable, exhibiting worst-case latencies exceeding 9 ms. In contrast, PREEMPT RT reduced the worst-case latency by nearly 88 percent to under 225 microseconds, enforcing a direct wake-up path that mitigates OS noise. These findings demonstrate that while PREEMPT RT resolves scheduling variance, the residual jitter on modern SoCs is primarily driven by hardware memory contention.

Andreas Schwierz, Håkan Forsberg

The usage of complex Microcontroller Units (MCUs) in avionic systems constitutes a challenge in assuring their safety. They are not developed according to the development requirements accepted by the aerospace industry. These Commercial off-the-shelf (COTS) hardware components usually target other domains like the telecommunication branch. In the last years MCUs developed in compliance to the ISO 26262 have been released on the market for safety-related automotive applications. The avionic assurance process could profit from these safety MCUs. In this paper we present evaluation results based on the current assurance practice that demonstrates expected assurance activities benefit from ISO 26262 compliant MCUs.

Andreas Schwierz, Håkan Forsberg

Dealing with Commercial off-the-shelf (COTS) com- ponents is a daily business for avionic system manufacturers. They are necessary ingredients for hardware designs, but are not built in accordance with the avionics consensus standard DO- 254 for Airborne Electronic Hardware (AEH) design. Especially for complex COTS hardware components used in safety critical AEH, like Microcontroller Units (MCUs), additional assurance activities have to be performed. All of them together shall form a convincing confident, that the hardware is safe in its intended operation environment. The focus of DO-254 is one approach called Design Assurance (DA). Its aim is to reduce design errors by adherence of prescribed process objectives for the entire design life cycle. The effort for certain COTS assurance activities could be reduced if it is possible to demonstrate, that the COTS design process is based on similar effective design process guide- lines to minimize desgin errors. In the last years, semiconductor manufacturers released safety MCUs in compliance to the ISO 26262 standard, dedicated for the development of functional safe automotive systems. These products are COTS components in the sense of avionics, but they are also developed according to a process that focuses on reduction of design errors. In this paper an evaluation is performed to figure out if the ISO 26262 prescribes a similar DA approach as the DO-254, in order to reduce the COTS assurance effort for coming avionic systems.