Seventh, safety test and health platform
Intelligent unmanned system is a typical complex system, and "complex system" generally refers to a class of systems with large scale, complex structure, various functions, diverse fault modes, and unknown and changeable external environment, which often has nonlinear, dynamic and changeable, large scale, multiple levels, decentralization and other characteristics, such as the human body, various vehicle systems, precision CNC machine tools and other mechanical or electrical systems, etc. These are typical examples of complex systems. With the increasing complexity of the system, the components and probability of failure are increasing. How to reduce the probability of failure and reduce the consequences of failure is the content that needs to be considered in system health and safety assessment.
Any unmanned system can be divided into several components (or subsystems), including physical components such as motors, propellers, gyroscopes, and virtual components such as wind, air pressure, and obstacles. Any component can be considered to contain three types of models: energy consumption model, motion model, and fault model. First, the motion model is responsible for describing the transient law of the component, and then the energy consumption model is used to describe the long state law of the component. The motion model and the energy consumption model together describe the normal short - and long-term operation law of the component, while the fault model describes the rule of the component deviating from the normal operation state due to various internal and external factors.
Body faults can be classified into power system faults, energy system faults, sensor faults, fuselage structure faults and control system faults according to the topological decomposition and formation types of subsystems.
The definition of safety of unmanned systems is quite different from that of manned systems. Therefore, the above paper focuses on the definition of safety of unmanned systems and the extension of safety assessment methods. As a typical complex system, the definition of health of unmanned systems is not fundamentally different from that of manned systems, but unmanned systems are more complex, with more factors to consider and more complicated processes.
First, the RflySim platform does offline evaluation, establishes preliminary failure mode and impact analysis table and historical database; Secondly, real-time online evaluation is conducted according to the output of offline evaluation. After a flight mission, real-time data is collected, health indicators and safety status of each subsystem are updated, and the failure mode and impact analysis table and historical database are updated, so that an offline to online evaluation is iterated repeatedly.