Stochastic Semi-active Control Method of Structure Based on Magnetorheological Dampers Considering Time Delay

Area of Science:

• Civil Engineering
• Control Systems Engineering
• Structural Dynamics

Background:

• Magnetorheological (MR) dampers are crucial for semi-active control in civil engineering structures.
• Time delays in feedback processes significantly reduce the reliability of structures under stochastic excitations.
• Existing control methods struggle to maintain structural integrity when faced with time delays.

Purpose of the Study:

• To propose a novel control method (SOSC-PSO) that compensates for time delays in MR damper systems.
• To enhance the reliability of civil engineering structures subjected to stochastic excitations.
• To optimize control parameters based on system reliability criteria.

Main Methods:

• Developed a Stochastic Optimal Semi-active Control method with time delay compensation (SOSC-PSO).
• Derived semi-active control force as a function of current and previous states to counteract time delays.
• Optimized key control parameters using a system reliability criterion.
• Validated the method on single-degree-of-freedom and multi-degree-of-freedom structures under seismic excitations.

Main Results:

• Time delays were confirmed to significantly degrade the performance of MR dampers.
• The SOSC-PSO method demonstrated substantial improvement in control effectiveness by compensating for time delays.
• Optimized parameters further enhanced the reliability of the structural control system compared to unoptimized methods.

Conclusions:

• The SOSC-PSO method effectively mitigates the negative impact of time delays in MR damper-based structural control.
• Parameter optimization based on reliability criteria is crucial for maximizing the performance and reliability of semi-active control systems.
• The proposed approach offers a robust solution for improving the resilience of civil engineering structures against seismic threats.