Metal Laser Sintering Combined with High Speed Milling is the technology in which high speed cutting is united with the selective laser sintering process. By changing the conditions of laser beam irradiation, it is possible to build a sintered porous media which has a hole in an arbitrary part by this process. If the mold tool of this structure is used for injection molding, it is proved that the compressed air imprisoned in the mold and the gas coming out of resin are discharged from it, poor molding can be reduced. However, as sintered porous media is hard to control for the size and position of an ordered macroporous structure, it is difficult to build porous media with an ordered macroporous structure deliberately. This results in a smaller amount of airflow and a greater variation in airflow. In order to solve this problem, latticework is proposed as a new gas permeable structure in this paper. Different from a lower density sintered structure, metallic powder is sintered and fused using a laser beam with a high energy density, and fusion is carried out into the latticework structure. The fused gaps of the structure serve as a hole. Since each hole will keep the position and become the ordered macroporous structure even if lamination continues, the improvement in performance of gas permeability is expected. The airflow equation for the structural design to satisfy a required airflow rate is also examined in this paper.

This paper describes the results of fundamental experiments conducted by injection mold with permeability fabricated by Metal Laser Sintering Combined with High Speed Milling. Metal Laser Sintering Combined with High Speed Milling is attracting attention as a new mold fabrication approach. This machining method combines the metallic powder layer fabrication method with high-speed cutting. Since this process does not have the problem of tool L/D in usual cutting, it provides outstanding shape machining performance of deep ribs etc. Moreover, with this processing method, sintered density can be controlled by changing the exposure conditions of the laser beam, and gas permeable structures can also be manufactured. This fabrication method does not require the mold to be divided. From these features, this method is expected to offer such advantages as quick delivery of molds and low manufacturing costs. However, little is known about the application of laser sintered metallic molds which have gas permeability structure to plastic injection molding, and the practical use of these molds is not easy. The aim of this research was therefore to investigate the gas permeable structures realized by laser sintered metallic mold in plastic injection molding The results confirmed that permeable injection molds are effective for influencing residue air in products.

This paper discusses design methods for the internal structure of molds used in production utilizing metal laser sintering combined with high speedmilling which selectively sinters metal powder to form a three dimensional mold. This milling technique is characterized by the fact that the selective laser sintering process and milling process are carried out in alternating sequence, achieving the level of processing accuracy demanded of mold production. In addition, in the selective laser sintering process, because the mechanical strength of the sintered body (Young’s Modulus) is variable, suitable interior structures that consider dynamic conditions are expected. However, in the current state of design, this structure is determined experimentally, and there is a high possibility of incurring unnecessary production time and high costs. In this paper, we investigate a method that incorporates an optimization method using stress that occurs within the structure interior, obtains the interior topological structure as a Young’s Modulus distribution, and designs a suitable interior structure using this distribution. As a result of investigation using numerical analysis, we obtained a structure that reduces the volume of the sintered body, having high mechanical strength in comparison with a conventional structure while improving structural rigidity.

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This paper deals with a kinematics resolution framework for robots controller to perform multi target positioning. The framework consists of metaphysical subsystems, corresponding to joint and link, and their connection rules. The localized forward and inverse kinematics calculations are embedded in the subsystems and kinematics models are composed of a set of subsystems assembled by their connection rules. The framework is applied to case studies of the forward and the inverse kinematics problems which are multi target positioning of five or more d.o.f. robot manipulator.