The push towards electric vehicles in modern times is complemented by mobile and renewablepower technology. In automotive vehicles, ride comfort and road handling are also important metrics to consider. Energy harvesting shock absorbers (EHSA) have potential, but traditional applications have resulted in tradeoffs between ride comfort, road handling, and power generation. Hence, research involving new technologies for power generation with multi-objective performance capabilities is very valuable. This work specifically investigates a novel approach for vibration suppression and electric power harvesting in systems subjected to stochastic and broadband excitations, focusing on automotive suspensions. The proposed solution harnesses the concept of inertance to provide mass amplification via rotational inertia and also introduces inertial nonlinearity, enhancing bandwidth and overall performance.This work specifically explores vibration suppression, energy transfer, and the qualitativechange in the probability density function (PDF) with the application of a device with nonlinearity due to inertia. This device is an inerter-based pendulum vibration absorber (IPVA). The change in the PDF is called P-bifurcation. The IPVA is first applied to a single-degree- of-freedom (SDOF) spring-mass-damper system subjected to white noise excitation. A perturbation method identifies and tracks bifurcation points, revealing that the marginal PDF of the pendulum’s angular displacement undergoes a P-bifurcation, transitioning from monomodal to bimodal behavior. A cumulant-neglect technique predicts the system’s mean squares, demonstrating significant vibration suppression near the P-bifurcation by transferring kinetic energy from the structure to the pendulum. Results are validated via Monte Carlo simulations (MCS), approximating the PDF and mean squares.The study extends to integrating energy harvesting into the nonlinear device, applying itto a quarter-car model under class C road conditions (average road, ISO 8608). The impact of pendulum length on power generation, ride comfort, and road handling is assessed. Near P-bifurcation, simultaneous enhancements are seen in power output (40%), ride comfort (60%), and road handling (60%) compared to a linear benchmark. A Wiener path integration (WPI) method predicts the PDF and its second derivative, enabling efficient detection of monomodal, bimodal, and rotational PDF regions in the noise intensity-electrical damping plane. MCS confirm performance improvements of up to 43% in energy transfer and 20% in power harvested compared to optimized linear systems, alongside at least 59% gains in ride comfort and road handling. A novel bifurcation detection algorithm reduces computational demands by linking qualitative PDF changes to performance metrics.Experimental studies verify P-bifurcation and the energy harvesting IPVA’s effectivenessin vibration reduction and energy harvesting for a SDOF structure under Gaussian broadband base excitation. Various experimental scenarios help identify unknown mathematical model parameters, minimizing discrepancies between experimental and simulated results for the pendulum’s velocity, with all RMS velocity differences below 3%. The fitted model predicts power, vibration suppression, and P-bifurcation boundaries in the noise intensity-electrical damping plane, corroborated experimentally. Power spectral density analyses reveal bimodal and rotational systems outperform monomodal configurations, enhancing power and suppressing resonant peaks by up to factors of four and two, respectively. Near resonance, mean square relative velocity improves by a factor of two.These findings inform the design and manufacture of a full-scale IPVA-integrated EHSAfor off-road vehicles. The shock design involves balancing durability, weight, ride comfort, energy harvesting, and road handling. The shock absorber undergoes sinusoidal testing on a hydraulic machine to fit a developed mathematical model. A nonlinear least-squares based optimization routine fits model parameters, yielding two viable parameter sets. Numerical simulations implement the shock in a quarter car model with class F road excitation (off-road; ISO 8608) and quantify energy harvesting, ride comfort, and road handling. A correlation between performance and the PDF shape is finally made.
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