Based on the finite element analysis method to simulate the O-P hardness. Taking S45C steel as an example, comparative analysis of O-P hardness of finite element simulation and O-P hardness of instrument indentation hardness experiment, results show that difference of S45C steel’s O-P hardness between the finite element simulation and real experiment is-2.62% Accordingly seen, O-P hardness can be obtained by finite element numerical simulation method, it’s a possible way to study relations between O-P hardness and Vickers hardness based on finite element numerical simulation techniques.

Method for determining the plastic properties of metallic materials was proposed based on the functional relationships between representative stress, representative strain and nominal hardness which were established with the aid of dimensional analysis and finite element simulation. The errors of 0.2% yield strength and strain hardening exponent of five engineering metals were from-17.1% to 15.4% and from -0.125 to 0.11, respectively,which satisfied the need of engineering application and verified the effectiveness of the method.

Finite element analysis is undertaken to identify the extent of loading deformation of instrumented indentation equipment frame which is a main part in High-precision instrumented indentation tester developed and realized by our group. The working load enacted in the model is varied from 10N to 100N, and the increment load is 10N. By plotting and fitting data of inclination angle and working load, the relationship between frame inclination angle and working load is established. The function of this relationship is θ=0.000024*F. When the working load is up to the upper bound 100N, the inclination angle of frame reaches the maximum value 0.00241°.Load analysis of push rod shows that the percent error between measured load values and real indentation load values caused by maximum inclination angle is in 10-8order. The conclusion is thus derived that frame inclination has nearly no effects on load measurement precision. The research in this paper confirms that the design of frame belonging to High-precision instrumented indentation tester is appropriate.

In order to package the apples automatically, a special kind of flexible manipulator was designed. The manipulator was composed of three fingers, and each finger consists two series joints with a single degree of freedom, torsion spring was installed on the joints. The two-joint finger is stretched by a cable-driven, which is connected to piston rod of cylinder, grasping apple force come from two torsion springs. The desination of manipulator based on the mechanical properties of apple. Based on the material funciton of special kind of apple, the spring parameters was optimized. The designed manipulator will have a good supple adaptation to different size apples without causing damage to apple.

Based on the finite element analysis method, the relationship between two systems of crack (radial crack and lateral crack) and pop-in phenomenon were compared during the instrumented indentation process in ceramic materials. In order to give a reasonable explanation for mechanism analysis of pop-in phenomenon in the process of ceramic materials instrumented indentation, this paper proposed the viewpoint that pop-in phenomenon is caused by the lateral crack in the process of ceramic materials instrumented indentation. This work provided a theoretical basis for the study of instrumented indentation methodologies based on the pop-in phenomenon to determining mechanical properties of ceramic materials.