Interval Sensitivity Analysis and Optimization of Magneto-Rheological Damper with Energy Harvesting Characteristics

In order to overcome the limitation of external power supply and complex maintenance of Magneto-Rheological (MR) damper, the MR damper with energy harvesting characteristics is proposed. The output damping force is the key point for energy harvesting MR damper to realize vibration control. Thus, the sensitivity and the contribution of key parameters to output damping force are meaningful to be explored, meanwhile, the contradiction between energy harvesting and vibration isolation performance should be compromised.

Firstly, the electro-mechanical output damping force model of MR damper with energy harvesting characteristics is established by Kirchhoff’s law and Bingham model. Subsequently, the electro-mechanical coupling dynamical model of semi-active suspension with energy harvesting characteristics is derived. The sky-hook control algorithm is conducted to eliminate external vibration. The vibration isolation performance is investigated in time and frequency domain respectively. The interval sensitivity analysis approach is conducted to investigate the sensitivity between key parameters of energy harvesting MR damper and output damping force. Furthermore, the orthogonal test approach is employed to determine the contribution of key parameters to output damping force. Finally, a multi-objective optimization is conducted by NSGA-II method to solve the contradiction between energy harvesting and vibration isolation capability.

Compared to passive control, sprung mass displacement root mean square (RMS) value and velocity RMS value of semi-active control are reduced by 72.05% and 38.24% in time respectively. The amplitude of displacement transmissibility of semi-active control decreases about 20dB compared to passive control. The interval sensitivity is increased by the selected key parameters increasing with different growth rate. Through orthogonal test, the contribution of each key parameters to output damping force is obtained. The inner and outer diameter of generating coil make most contribution to output damping force, which are 1260.96 and 878.19 respectively. After multi-objective optimization, the output damping force is increased by 12.31%, and the displacement is reduced by 8.44%.

The sensitivity of key parameters to output damping force is analyzed by interval sensitivity approach. Furthermore, the contribution of key parameters to output damping force is obtained by orthogonal test. The sensitive key parameters are optimized to increase the value of output damping force for improving the vibration isolation performance. The proposed method makes a novel design approach for MR damper with energy harvesting characteristics, which exhibits important practical values.