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Traditionally, safety-critical projects have been de- veloped using the waterfall process. However, this makes it costly and challenging to incrementally introduce new features and to certify the modified product for use. As a result, there has been increasing interest in adopting agile development paradigms within the safety-critical domain. This in turn intro- duces numerous challenges. In this paper we address the specific problems of discovering, analyzing, specifying, and managing safety requirements within the agile Scrum process. We propose SafetyScrum, a methodology that augments the Scrum lifecycle with incrementally applied safety-related activities and introduces the notion of “safety debt” for incrementally tracking the current safety status of a project. We demonstrate the viability of SafetyScrum for managing safety stories in an agile development environment by applying it to a project in which our existing Unmanned Aerial Vehicle system is enhanced to support a River- Rescue scenario. 

Research in the area of Cyber-Physical Systems (CPS) is hampered by the lack of available project environments in which to explore open challenges and to propose and rigorously evaluate solutions. In this “New Ideas and Emerging Results” paper we introduce a CPS research incubator – based upon a system, and its associated project environment, for managing and coordinating the flight of small Unmanned Aerial Systems (sUAS). The research incubator provides a new community resource, making available diverse, high-quality project artifacts produced across multiple releases of a safety-critical CPS. It enables researchers to experiment with their own novel solutions within a fully-executable runtime environ- ment that supports both high-fidelity sUAS simulations as well as physical sUAS. Early collaborators from the software engineering community have shown broad and enthusiastic support for the project and its role as a research incubator, and have indicated their intention to leverage the environment to address their own research areas of goal modeling, runtime adaptation, safety-assurance, and software evolution. 

Small Unmanned Aircraft Systems (sUAS) are an emerging application area for many industries including surveillance, agriculture monitoring, and vector-borne disease control. With drastically lower costs and increasing performance and autonomy, future application evolution will more than likely include the use of sUAS swarms. Several largely successful experiments in recent years, using off the shelf sUAS, have been conducted to address the long standing challenge of controlling and monitoring vector-borne diseases. In this paper we build on lessons learned from these prior efforts, and discuss ways in which swarms of sUAS could be deployed to place and monitor Autocidal Gravid Ovitraps for reducing the mosquito population. 

The growing adoption of small unmanned aircraft systems (sUAS) for tasks such as eCommerce, aerial surveillance, and environmental monitoring introduces the need for new safety mechanisms in an increasingly cluttered airspace. Safety assurance cases (SAC) provide a state-of-the-art solution for reasoning about system and software safety in numerous safety-critical domains. We propose a novel approach based on the idea of interlocking safety cases. The sUAS infrastructure safety case (iSAC) specifies assumptions and applies constraints upon the behavior of sUAS entering the airspace. Each sUAS then demonstrates compliance to the iSAC by presenting its own (partial) safety case (uSAC) which connects to the iSAC through a set of interlock points. To enforce a “trust but verify” policy, sUAS conformance is monitored at runtime while it is in the airspace and its behavior is described using a reputation model based on the iSAC’s expectations of its behavior.