Multi-Mode Controller Design for Active Seat Suspension with Energy-Harvesting 2020-01-1083

In this paper, a multi-mode active seat suspension with a single actuator is proposed and built. A one-DOF seat suspension system is modelled based on a quarter car model of commercial vehicle with an actuator which is comprised of a DC motor and a gear reducer. Aiming at improving ride comfort and reducing energy consumption, a multi-mode controller is established. According to the seat vertical acceleration and suspension dynamic travel signals, control strategies switch between three modes: active drive mode, energy harvesting mode and plug breaking mode. In active drive mode, the DC motor works in driving state and its output torque which calculated by LQR algorithm is controlled by a current-loop controller; In energy harvesting mode, the DC motor works in generator state by which induced current can charge the power source, in this mode, the DC motor is considered as a damper which damping coefficient is decided by the charging current and controlled by Skyhook algorithm; In plug breaking mode, the DC motor works in the plug breaking state and its inverse voltage reaches to maximum to stop the suspension movement quickly. Simulations are carried out with random road and triangle block as the road excitation. The simulation results show that the multi-mode control strategy improves the ride comfort a lot compared with passive seat suspension, which effectively reduces energy consumption compared with fully active control strategy meanwhile.