Composite cylinder monitoring system

A method comprising:

• passively detecting, by a plurality of sensors connected to a composite cylinder, deformation data associated with the composite cylinder, by receiving vibration from an impact;
• determining, by a controller communicatively coupled to the plurality of sensors, a damage value based on the detected deformation data when the composite cylinder endures impact damage;
• communicating, by the controller, a notification when the damage value exceeds an impact damage threshold;
• controlling, by a filling controller communicatively coupled to the plurality of sensors, a valve for filling the composite cylinder with a fluid;
• passively detecting, by the filling controller, damage to the composite cylinder as the composite cylinder is filled with the fluid, the damage detected based on the deformation data from the plurality of sensors;
• and
• automatically performing a safety action when the damage to the composite cylinder is detected.

A monitoring system comprising:

• a plurality of piezoelectric sensors connected to a composite cylinder having a laminate structure, each piezoelectric sensor of the plurality of piezoelectric sensors configured to passively detect deformation data associated with the composite cylinder without emitting signals to be detected by respective other sensors when the composite cylinder is impacted by an object and when the composite cylinder is filled with a fluid by detecting out-of-plane displacement of the laminate of the composite cylinder and transducing stress waves into a voltage;
• and
• a controller communicatively coupled to the plurality of piezoelectric sensors and configured to:
• receive, from the plurality of piezoelectric sensors, the detected deformation data associated with the composite cylinder when the composite cylinder is impacted by an object,
• determine a direct wave energy from the object based on the detected deformation data when the composite cylinder is impacted by the object, the direct wave energy being used to mitigate reflections and wrapping waves and determined based on a direct arrival time of a slowest moving wave component from an impact location and the voltage detected at each of the plurality of sensors, and
• communicate a notification when a damage value exceeds an impact damage threshold,
• wherein the plurality of piezoelectric sensors are communicatively coupled to a filling controller configured to:
• control a valve for filling the composite cylinder with the fluid,
• receive, from the plurality of piezoelectric sensors, deformation data associated with the composite cylinder while the composite cylinder is being filled with the fluid,
• detect damage to the composite cylinder as the composite cylinder is filled with the fluid using a modal acoustic emission inspection, the modal acoustic emission inspection being based on at least one of:
• a fiber tow fracture indicator corresponding to detected fiber tow fracture events being quantified and compared to a fiber tow fracture threshold, an instability indicator corresponding to instability within a local volume of material above an instability threshold, a delamination event indicator corresponding to delamination of one or more layers of the composite cylinder above a delamination threshold, a damage mechanism indicator corresponding to damage mechanisms accumulated in the local volume of material above a damage mechanism threshold, or a fretting emission indicator corresponding to fretting emission above a fretting emission threshold based on a laminate composition of the composite cylinder, and
• automatically perform a safety action when the damage to the composite cylinder is detected.