How can you ensure control system safety in extreme conditions?

2 Design for redundancy and diversity

Redundancy and diversity are two key principles for enhancing control system reliability and fault tolerance. Redundancy means having multiple copies or backups of the same function or component, so that if one fails, another can take over. Diversity means having different types or methods of performing the same function or component, so that if one is affected by a common cause, another can avoid it. For example, a control system may have redundant sensors, actuators, and controllers, as well as diverse algorithms, architectures, and communication channels.

3 Implement robust and adaptive control

Robust and adaptive control are two types of control techniques that can help control systems cope with uncertainties and disturbances. Robust control means designing a control system that can maintain stability and performance under a given range of variations in the system parameters, inputs, and outputs. Adaptive control means designing a control system that can adjust its parameters or structure in response to changes in the system dynamics, environment, or objectives. For example, a control system may use robust control to handle sensor noise or actuator delays, and adaptive control to compensate for aerodynamic changes or damage.

4 Test and verify extensively

Testing and verification are crucial steps for ensuring control system safety, as they can identify and eliminate errors, bugs, and failures before they cause harm. Testing means applying various inputs and scenarios to the control system and observing its outputs and behaviors. Verification means checking whether the control system meets the specified requirements and specifications. Testing and verification can be done at different levels, such as component, subsystem, system, and integration, and using different methods, such as simulation, analysis, experiment, and inspection.

5 Monitor and diagnose continuously

Monitoring and diagnosis are important functions for maintaining control system safety, as they can detect and diagnose faults, anomalies, and degradation in real time. Monitoring means collecting and analyzing data from the control system and its environment, such as sensor readings, actuator commands, controller states, and performance indicators. Diagnosis means identifying and locating the source and severity of the faults, anomalies, and degradation, using techniques such as fault detection and isolation, fault identification and estimation, and fault prognosis and prediction.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?