Contents of the Journal of Mechanical Engineering 51, 1 (2000)

L. STAREK, J. KUBLA: Smart and intelligent material systems (in Slovak)      1

R. ISTENIK: Design of dynamic model of contact for solution of impact 
actions in mechanical systems                                               35

E. MIKO: Verification of the model of roughness formation on obliquely
turned surfaces                                                             50

This article provides a summary of the current state of smart and intelligent material systems. The use of shape memory alloys, piezoceramics, and electrorheological fluids in a variety of smart and intelligent material systems is covered. A description of basic material configuration used in controllable system components, as well as a discussion of controllable devices such as programmable beam, clutches, and dampers, is presented. Models that have been developed to simulate the response of such structures are summarised. Throughout the paper an attempt to identify current and future key areas of research and development in smart and intelligent material application technology is made.

In the paper a model of contact for investigation of impacts in mechanical systems with contacts and clearances is suggested. The suggested model describes impact effects of one-dimensional character with both the transverse deformation and vibration neglected, e.g. an impact in a system which may contain elastic prismatic rods (e.g. valve gears). The impacting body may be represented by a separate equivalent dynamic system consisting of discrete elements (masses, springs, and dampers). In the paper there is also a proposal of a special prismatic bar for the dynamic substitution of an impacting rod and a proposal for experimental determining of contact damping. The contact model was proposed and applied that considers its non-linearity, energy dissipation caused by impact and eventual influences of a lubricant oil. One of the aims was determination of the impact energy loss in the contact.

The paper discusses a model of roughness formation on surfaces obliquely turned with a no-corner rectilinear cutting edge tool. The model provides a quantification of the effect that the edge mapping, the non-removable part of machining allowance, the relative shifts in the tool-work system, and, finally, the edge wear have on the roughness of obliquely turned surfaces. The relative shifts as well as the non-removable part of machining allowance constitute a limitation for the roughness of machined surfaces.
The developed model was verified in laboratory conditions and the obtained results confirm that the model can be used for the description of roughness of obliquely turned surfaces.