To reduce the cavitation occurring on valve plate of typical Swashplate piston pump, an optimization design method was introduced to quantitively analyse the accurate relationship between structural jet grooves parameters and cavitation.Using the CFD method, the sunking and discharging process in piston pump was simulated dynamically.The damp grooves structure effect on both jet angle and pressure shock were analysed visually with a series of different parametrical grooves.By establishing parametrical damp groove model, the piston pumps dynamic analysis was integrated with the technologies of CFD analysis, experimental design and approximation model, etc.The mathematical model of plunger pressure in oil back period, jet angle and structural parameters of damp groove were established in the form of second-order RSM model. The damp groove structure of valve plate was optimized on the basis of the RSM model.Test data show that the anti-cavitation performance of optimized valve plate was increased obviouslyAnd this method provided theoretical foundation for the structure design of damp groove.

To solve the problems of concrete piston striking cylinder and pumping insufficiency caused by the mismatch between varying loads and system’s open-loop control property, the optimal model of concrete pumping displacement control was built.To be precise, the displacement control signal parameters were taken as control variables, and the location parameter of the main cylinder’s displacement sensor was taken as structure variable. under the physical constraint condition of non-collision between piston and cylinder, the piston stroke maximizing was taken as objective function and the optimal model of concrete pumping displacement control was built.Optimization result shows that piston of concrete pumping system don’t strike cylinder and pump sufficiently under varying loads.This optimal model, which is built in the integration design space of structure variable and control variables, is of guiding significance for solving open-loop system’s engineering control problems.

A robust optimization approach of an accelerometer is presented to minimize the effect of variations from micro fabrication. The sensitivity analysis technology is employed to reduce design space and to find the key parameters that have greatest influence on the accelerometer. And then, the constraint conditions and objective functions for robust optimization and the corresponding mathematical model are presented. The optimization problem is solved by the Multiple-island Genetic Algorithm and the results show that an accelerometer with better performance is obtained.

In this paper, functions of intelligent fault monitoring system of hydraulic excavator are analyzed. Architecture of the fault monitoring system is presented. Key technologies of the monitoring system are discussed detailed. Key parts of the fault monitoring system such as inspection controller, travel controller and programmable monitor, remote monitoring system is developed. As a result, the intelligent monitoring system is of great useful for monitoring the faults of hydraulic excavator.

In order to improve the comprehensive performance of concrete truck mixer, considering the kinetics between concrete and blade, a parametric design model is built to find the relation between the parameters of the blade and performance. Based on subdividing function, the drum is divided into different parts called helix, the helix is designed as different blades for each part, then all the blades are combined into a complete helix. According to the design requirements (slump, the bevel angle of the drum), the corresponding blades are created. The simulation and engineering test show that this parametric design model can improve the comprehensive performance, besides, this method provide a new way to solve the detail design problem between multiphase and blade.