Resilient cooperation and perception for multi-agent systems in adversarial settings

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Bio-inspired approach for adaptive monitoring and fault-tolerant control of electro-hydraulic actuators

The human body regulates blood flow and pressure through feedback mechanisms that help maintain stable hemodynamic conditions. For example, in cases of acute bleeding, blood pressure drops due to a loss of blood volume. In response, a compensatory feedback mechanism detects the drop and triggers reflex tachycardia—a physiological response that increases heart rate to help offset the pressure loss.
Inspired by such physiological feedback mechanisms, we propose a reconfigurable, fault-tolerant control and monitoring framework for electro-hydraulic systems to address performance degradation, particularly pressure drops caused by leakage faults. The framework incorporates two concurrent feedback mechanisms designed to maintain system performance and stability under faulty conditions. First, an adaptive monitoring algorithm detects pressure drops and reconstructs the underlying leakage faults responsible for performance degradation. Then, the adaptive feedback loops leverage the signals from the monitoring algorithm to regulate the system's supply pressure and adjust the actuator control algorithm accordingly. These adaptive feedback-control strategies enable resilience and fault tolerance in the system.

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A bio-inspired approach for increased efficiency of servo actuators through a switching control configuration

In nature, the movement of some animals is closely influenced by their environment—a form of mobility known as passive locomotion. In this mode, environmental flow (air or water) acts as propulsion, carrying the animal in the same direction. For instance, jellyfish and flatworms drift with the current, while species like the blue crab and continental-shelf fish such as plaice can sense tidal flow direction and exploit it to enhance their swimming speed. In engineering, hydraulic actuators often interact with their environment to exert forces and torques. When the external load aligns with the actuator’s intended motion, it can serve as an assistive force. This research aims to leverage such external loads as a form of assistive propulsion in position control, providing a secondary energy source that improves system efficiency. To this end, a new configuration of control valves is used to have a controllable supply pressure regulating the system pressure according to the actuator's demands. When assistive loads are present, the system pressure decreases and allows the external force to contribute to movement. A switched H-infinity control strategy is used to synthesize suitable control algorithms for position control in these different modes.