The Influence of Cargo Moving and Sliding Mode Control Strategy for Forklift

Considering the movement of synthetic center of gravity of forklift caused by the cargo moving, a vehicle model including the cargo weight and its moving speed is established. Based on this model, a lateral stability controller with uncertain parameters is proposed. The proposed controller controls the four-wheel steering (4WS) forklift by analyzing feedback compensation angle which can realize fast tracking of the ideal yaw rate and sideslip angle with high robustness, solve the problem of insufficient lateral stability caused by the movement of cargo under the turning condition and improve the working efficiency of forklift. Under the operation conditions of a step input and double-lane-change (DLC) maneuver, the built forklift model is simulated and proved to be valid. Combined with the vehicle test, it is verified that the above control strategy can optimize the dynamic response indexes such as yaw rate and sideslip angle of the forklift and improve the impact of cargo moving on the lateral stability of forklift.