A study of vibration control of truck seat suspension system
Creators: name: Zhao, Yuli
Publisher: name: RMIT University
Year: 2024
Subjects: classificationCode: 400203
subject: Automotive mechatronics and autonomous systems
classificationCode: 400702
subject: Automation engineering
classificationCode: 401702
subject: Dynamics, vibration and vibration control

description: The research has designed a novel active truck seat suspension system for a further study of active vibration control. A 5-degree-of-freedom driver and seating suspension system model for active vibration control has been developed. A novel fast system parameter identification method from vibration measurement data has been proposed for the seat-occupant system based on the multi-objective Genetic Algorithm optimization (GA). This system parameter identification method can identify the system parameters of a 5 degree-of-freedom lumped mass-spring-dashpot biodynamic seat-occupant model from vibration test results quickly and accurately. Without calculation and measurement of materials, the physical parameters of the seating suspension system such as mass (m), stiffness (k), and damping coefficients (c) are estimated by matching the measured resonant frequency and peak transmissibility amplitude at a specific frequency with the simulated ones. This is one of the main contributions of this paper. The characteristics of the human body vibration in the low-frequency range are analyzed through the seat to head transmissibility (STHT) ratio. The experimental and simulation results of the STHT values have been compared to verify each other. The sensitivity analysis of the seat effective amplitude transmissibility (SEAT) values over the seating system parameters have been conducted and validated by the measured results of the transmissibility ratios. This has answered the first research question.

A response surface method (RSM) model has been developed to establish a relationship between the vibration isolation performance target and input design parameters from any measurement or simulation results. The statistical significance of the RSM model has been validated by analysis of variance (ANOVA). The sensitivity analysis of design parameters and their interaction effects have been conducted. The design parameters have been optimized through RSM modeling and the genetic algorithm (GA). It is concluded that to mitigate the low-frequency vibration, the addition of a seat cushion with small stiffness and damping coefficients and use of the commercial vehicle seat with the small seat structure stiffness and damping coefficients are most effective for the system vibration isolation. The results of the response surface method have been verified by those of the artificial neural network modeling and linear regression modeling in this thesis. This has answered the second research question.
Finally, a novel type of active seating suspension system combining timing belt, servo motor, and traditional x-shaped seat structure has been proposed and designed for vibration control. The design fully considers the packaging space of the seating suspension system, including the reduction of the system volume and noise. This has answered the third research question.