Group shop has the character of job shop and open shop, one robot is used to transport material, and the robotic cell produces multiple types of parts for a long time. In order to improve throughput, or minimize the cycle time, we establish the model of robotic cell, develop optimizing algorithm, and do computational experiments to find the better activity sequence for the robot.

The deflection of thin-walled components during machining will seriously affect their machining accuracy and surface quality. This paper presents a state of art review for the research in error prediction and error compensation during machining of these components. Some key techniques, such as the overall scheme, the cutting stability, the machining force modeling methodologies, the machining deformation analysis methodologies based on FEA and NC compensation methodologies, are discussed. The problems which have been highlighted in the research papers are pointed out and some problems which should be further investigated are given.

Complex surfaces have been widely used in engineering. However, the current general-purpose CAD systems do not provide the modeling method of some kinds of complex surfaces such as parametric surfaces. In this paper, complex surfaces are generated by calculating the coordinates of the data points on the surfaces, creating the data files, importing the files into UG (Unigraphics), and then making use of the surface modeling functions of this software. Taking a bicubic B-spline surface for an example, the main steps of modeling of complex surfaces are presented and the modeling errors are analyzed in detail. A test is conducted to verify this approach.