Ball Screw-Based Series Elastic Actuator-Driven Suspension and Cabin Heave Acceleration Vibration Suppression Control for Vehicle Ride Comfort Enhancement

Abstract

This article presents a ball screw-based series elastic actuator-driven suspension (BSSEA-S) and a control framework to suppress cabin heave acceleration vibrations, thereby enhancing vehicle ride comfort. By incorporating series elasticity (SE) into a conventional ball screw-based rigid actuator-driven suspension (BSRA-S), the BSSEA-S implements a series elastic actuator (SEA) mechanism that mitigates the inertial effects and friction of the ball screw. This improves sensitivity to external inputs, enabling smooth and rapid responses to road inputs. The mechanical advantages of the BSSEA-S are validated through dynamics analysis and quarter-car (QC) model simulations. The control framework utilizes the incorporated SE to achieve highly sensitive and direct force control of the suspension, serving as an inner-loop controller that replaces the conventional damping force and functions as an ideal force source. This controller estimates suspension travel via kinematic relationships and applies appropriate control forces, allowing adjustable suspension characteristics. Building upon the inner-loop controller, an outer-loop controller implements sprung mass acceleration feedback control, designed using the system's frequency response data (FRD) and Nyquist plots. The design accounts for realistic system characteristics, including the inner-loop controller, reducing the system's sensitivity function within the frequency range critical to ride comfort. Experiments using the developed BSSEA-S and an experimental apparatus under various road inputs, including speed bumps and ISO class D random roads, validate enhanced ride comfort by suppressing cabin heave acceleration vibrations over a wide frequency range.