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This paper reports on an investigation treating a hard-milled surface as a surface undergoing severe plastic deformation at elevated temperatures. This surface exhibits remarkable magnetic anisotropy (expressed in term of Barkhausen noise). This paper also shows that Barkhausen noise emission in a hard-milled surface is a function of tool wear and the corresponding microstructure transformations initiated in the tool/machined surface interface. The paper discusses the specific character of Barkhausen noise bursts and the unusually high magnitude of Barkhausen noise pulses, especially at a low degree of tool wear. The main causes can be seen in specific structures and the corresponding domain configurations formed during rapid cooling following surface heating. Domains are not randomly but preferentially oriented in the direction of the cutting speed. Barkhausen noise signals (measured in two perpendicular directions such as cutting speed and feed direction) indicate that the mechanism of Bloch wall motion during cyclic magnetization in hard-milled surfaces differs from surfaces produced by grinding cycles or the raw surface after heat treatment.

This paper describes the design of machine tool based on the mechanism with parallel kinematic structure (PKS) called hexapod. The advantages of mechanisms with PKS predetermine them to the field of machining and robotics. Machine tool is designed like fully automated device contains system for automatic tool and part changing too. There was necessary to solve also a question of operation safety according to the real risk of injury. Some information about the design process, main requirements, the problems and the final solution can be found in this paper.

This paper deals with investigation of hard milled surface as a surface undergoing severe plastic deformation at elevated temperatures. This surface exhibits quite remarkable magnetic anisotropy (expressed in term of the Barkhausen noise) and differs from ground surfaces. The main reason can be viewed in specific structure and the corresponding domains configuration formed during rapid cooling following after surface heating. Domains are not randomly but preferentially oriented in the direction of the cutting speed at the expense of feed direction. The Barkhausen noise signals (measured in two perpendicular directions such as cutting speed and feed direction) indicate that the mechanism of the Bloch wall motion during cyclic magnetization in hard milled surfaces differ from surfaces produced by grinding cycles or the raw surface after heat treatment.

This paper is focused on studies of selected process parameters of mechanism with hybrid kinematic structure called Trivariant. Small-scale prototype of Trivariant can work as a machining center with 5 Degrees of Freedom (DOF) as well as a robot with 6 DOF. In the paper is circumscribed field of mechanism workspace. All analyses are performed in selected levels of workspace.