Anti-rollover of the counterbalanced forklift truck based on model predictive control

To reduce the probability of a rollover accident of a forklift during high-speed steering, a hydraulic support cylinder is designed as an actuator to provide lateral support for the forklift. Aiming at the problem of judging the safety domain in the process of forklift driving, this paper proposes a strategy for dividing the forklift's driving state on the basis of the zero moment point. The relationship between the zero moment point's lateral component and the forklift's support plane is used as the basis for division. The forklift rollover process is divided into a safe stage, a controllable danger stage, and a critical rollover stage. In the safe stage, the cylinder does not provide support force, and in the controllable danger stage, the cylinder support force is adjusted on the basis of the model predictive control algorithm to adjust the forklift. The cylinder can be controlled to provide maximum support for the body during the critical rollover phase. This method takes the three-degrees-of-freedom forklift anti-rollover model as the control object and serves as the basis for the calculation of the zero moment point. The anti-rollover controller is built in MATLAB/Simulink to simulate the European standard operating conditions and to verify the actual vehicle test. Results show that the predictive control of the forklift anti-rollover model based on the zero moment point can effectively improve the body attitude of the forklift during high-speed steering and prevent the forklift from rolling over.