The invention belongs to the field of control of an electro-hydraulic
servo system, and relates to a force / position cooperative control method of an electro-hydraulic
servo system. In the implementing process of the method, a position output
signal and a
force output signal of a valve control cylinder of the electro-hydraulic
servo system in a work process are analyzed, outer-
loop control of force is additionally provided as feedforward compensation based on
position control, a
PID controller and an adaptive
fuzzy neural network controller are designed to respectively and individually control a
position control portion and a force control portion, and cooperative control of the position
signal and the force signal of the electro-hydraulic servo system is finally realized. The object of the invention is to reduce the vibration and the
impact in the work process of the electro-hydraulic servo system due to stress and improve the positioning precision and stability of the system. The method includes steps: the
position control portion measures the position output signal of the valve control cylinder through a displacement sensor and feeds back the position output signal to a position signal input portion, the position output signal is compared with an input signal, and a
position error signal is obtained; the force control portion measures the
force output signal of the valve control cylinder through a
force transducer and feeds back the
force output signal to a force input portion, the force output signal is compared with a force input signal, and a corresponding force
error signal is obtained; and finally the
error signal of the position control portion and the
error signal of the force control portion are added (namely the force error signal is regarded as feedforward compensation) as a position expected input error signal of the whole valve control cylinder, the valve control cylinder dynamically adjusts the position signal and the force signal of the valve control cylinder by employing incremental control, and cooperative control of the position and the force of the electro-hydraulic servo system is finally accomplished.