Mechanical Modelling of Active Seat Suspension System Based on Scott-Russell Mechanism

This work presents a dynamic simulation model of an active seat suspension system for passenger vehicles. The system is based on a Scott-Russell mechanism actuated by an electric motor and spindle drive, designed to improve ride comfort by reducing vertical vibrations while maintaining seat stability. A lumped inertia approach is employed to reduce the system’s inertias to the motor axis, accounting for motor, H-frame, and passenger-seat masses. Nonlinearities of the mechanism and friction effects modelled using a dynamic Dahl model are integrated into the model. Initial model verification for sinusoidal seat position control reveal frequency-dependent effects: friction dominates at low frequencies, while inertia becomes significant at higher ones, requiring increased motor torque. The model captures the essential dynamics of the system and provides a foundation for the development of advanced control strategies for active seat suspension.