## 3 System Design
### System Architecture
* Safety Executive: The Safety Executive (SE) processes all information from safety management capabilities and provides that information to the mission executive for execution. The SE will prioritize which safety feature should be addressed first (if multiple safety issues are occurring at the same time) and determine the recommended actions. * Collision Avoidance: Collision Avoidance algorithms for both ground collision and air-to-air would reside within the safety management area. These algorithms would determine when the vehicle is at risk of impacting something and provide recommended action(s) to avoid these problems. * Flight Termination: Flight Termination is a key issue for unmanned air vehicles. Flight termination can include destructive actions which result in the destruction of the vehicle. However, it can also contain contingency efforts that include immediate landing, reduction in system capabilities, flight-plan alteration, or other functionalities depending upon the mission and range requirements. Geo-Fence: The geo-fence capability defines the areas within or outside of which a vehicle should maintain a presence. There may be unique mission requirements that require a system to fly in certain areas which the geo-fence may not allow based upon changes in mission or knowledge of areas of operation. If the vehicle is approaching a fence limit or has crossed a fence, the safety system should direct the vehicle back within the defined boundary. This geo-fence could be dynamic based upon known aircraft (air collision avoidance), major changes in weather (weather avoidance), or known threats and borders. 5. Weather Avoidance: Depending on vehicle capabilities or mission sensor capabilities and requirements there may be a need to avoid undesirable weather. Weather avoidance would provide keep-out areas to the safety executive that could be provided to either the mission executive or the geo-fence capability for management of vehicle path. For sensor functionality issues it would be more critical to provide that information to the mission executive for determination of path route and sensor tasking. 6. Population Avoidance: Mission requirements may require the vehicle to perform tasks in areas with significant or critical populations. As a result, there may be a need to fly close to population but avoid interference or impact with people and activities. The population avoidance functionality would determine where the vehicle needs to be to avoid the population of concern and provide the safety executive of how to react to the given situation. 4. Communications Management Communities Management provides the key interface between the vehicle and other systems. The ability to send and receive both mission information and sensor data can be critical to the success of a given mission. By managing communications separately from the primary processes, it enables changes in communication methods without impacting the underlying functionality of the vehicle. Communications Management will divide the data as either mission management, mission sensor, and planning and intent. There are five primary functions within the Communications Manager: 1. Communications Executive: The communications executive provides the primary interface between the mission executive and the installed communication systems. The communication systems installed could vary depending on the vehicle type and mission requirements. The communication executive will provide external communications and data dissemination as required. The system will also need to recognize when communications are not being received for potential operations in a denied environment. 2. Communications Systems: The vehicle could have one or multiple communication systems installed for external communications capabilities dependent on mission requirements and vehicle capabilities. Communication types could include line of sight RF, satellite communications, optical/laser or others. Dissemination of data received and to be sent will be via the communications executive. 3.