A procedure for the automatic generation of the robot programming used in manufacturing operations is introduced in the present paper. The off-line programming system developed here includes graphical simulation of the robot and its workcell, kinematic model of the robot, motion planning and creation of the NC code for manufacturing process. The proposed system is applied in a robot with five revolute joints for manufacturing operations and in a robot with six revolute joints for welding operations.

Nanoindentation testing is used in this paper in order to investigate the mechanical properties of specimens with varying weight percentage of fumed silica using a low-viscosity liquid epoxy resin as a matrix. Controversial results are reported in the literature regarding the elastic modulus of fumed silica epoxy nanocomposites using conventional tensile tests, thereby there is much scope in investigating comparatively such systems in a nanometer scale. The results show that the hardness and modulus of the nanocomposites steadily decrease with increasing fumed silica content which was attributed to the severe tendency for cluster formation as studied by optical microscope and scanning electron microscope analysis. The variations in elastic modulus as measured using the nanoindentation testing technique revealed small differences from the tensile test data. A material-depending calibration procedure has been used by utilising the epoxy elastic modulus as measured by the tensile tests in order to account for the indentation inherent uncertainties in the tip shape calibration. The results demonstrate that the nanoindentation testing technique is an effective mechanical testing method for epoxy nanocomposites when an appropriate calibration procedure is followed.

In the present paper a continuous Finite Element Analysis (FEA) simulation method of the ball indentation hardness test is introduced in order to describe the deformation behavior of nanosilica composites and with this to extract precisely the material's stress-strain behavior. The developed procedure demonstrate in particular the adequacy of this method to determine the nanocomposites' elastic modulus which is compared with Halpin-Tsai and Lewis-Nielsen models as well as with experimental measurements taken from uniaxial tensile tests. The fracture area of all the tensile specimens was examined using a scanning electron microscope (SEM). It is shown that the correlation between the experimental results, the semi-empirical models and the FEA computational models concerning the elastic modulus values was satisfactory with very small deviations.

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