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Stiffness control of redundant robot arm, aimed at using extra degrees of freedom (DoF) to shape the robot tool center point (TCP) elastomechanical behavior to be consistent with the essential requirements needed for a successful part mating process, i.e., to mimic part supporting mechanism with selective quasi-isotropic compliance (Remote Center of Compliance – RCC), with additional properties of inherent flexibility.

Theoretical analysis and synthesis of the complementary projector for null-space stiffness control of kinematically redundant robot arm. Practical feasibility of the proposed approach was proven by extensive computer simulations and physical experiments, based on commercially available 7 DoF SIA 10 F Yaskawa articulated robot arm, equipped with the open-architecture control system, system for generating excitation force, dedicated sensory system for displacement measurement and a system for real-time acquisition of sensory data.

Simulation experiments demonstrated convergence and stability of the proposed complementary projector. Physical experiments demonstrated that the proposed complementary projector can be implemented on the commercially available anthropomorphic redundant arm upgraded with open-architecture control system and that this projector has the capacity to efficiently affect the task-space TCP stiffness of the robot arm, with a satisfactory degree of consistency with the behavior obtained in the simulation experiments.

A novel complementary projector was synthesized based on the adopted objective function. Practical verification was conducted using computer simulations and physical experiments. For the needs of physical experiments, an adequate open-architecture control system was developed and upgraded through the implementation of the proposed complementary projector and an adequate system for generating excitation and measuring displacement of the robot TCP. Experiments demonstrated that the proposed complementary projector for null-space stiffness control is capable of producing the task-space TCP stiffness, which can satisfy the essential requirements needed for a successful part-mating process, thus allowing the redundant robot arm to mimic the RCC supporting mechanism behavior in a programmable manner.

The purpose of this paper is to provide a method for the generation of information machines for part mating process diagnosis. Recognition of contact states between parts during robotized part mating represents a significant element of the system for active compliant robot motion. All proposed information machines for contact states recognition will recognize one of the possible contact states even when irregular events in the process occur, and the active motion planner will continue to send commands to robot controller according to the planned trajectory.

The presented framework is based on the general theory of automata and formal languages. Starting from possible regular contact states transitions in part mating, the authors create an automaton for diagnostics, which, besides regular, accepts all irregular (observable and unobservable) process sequences.

Contact states do not appear arbitrarily during regular processes, but in certain context. Theory of automata represents a solid basis for contextual recognition and diagnosis of irregularities in part mating.

The proposed methodology is elaborated and experimentally verified using an example of cylindrical part mating, and stick-slip effect as an observable irregularity. The future work will address the generation of diagnosers for other types of part mating tasks and extension of the set of observable irregularities.

The process diagnosis increases the robustness of active compliant motion system.

Although very important feedback information provider for active motion planner, part mating process monitoring was not frequently addressed in the past. In this paper, the authors propose a methodology for generation of part mating process diagnoser that is based on general automata theory.

This chapter presents findings from a study into reading interests and habits of prisoners in six Croatian penitentiaries, and their perception and use of prison libraries. The study was conducted with the help of self-administered print survey. A total of 30% of prison population (male and female) in selected prisons was included in the study and a total of 504 valid questionnaires were returned (response rate of 81.3%). Findings indicate that reading is the respondents’ most popular leisure activity and that they read more now than before coming to prison. Respondents read more fiction than non-fiction. Most frequently they read crime novels, thrillers, and historical novels. To a lesser degree, they read religious literature, biographies, spiritual novels, social problem novels, self-help, war novels, science fiction, erotic novels, romances, spy novels and horrors. Respondents would like to read daily newspapers and magazines, and books about sport, health, travel, computers, hobbies, cookbooks, etc. Respondents have wide reading interests (both in relation to fiction and non-fiction) but they do not have access to them in their prison library. Respondents reported that reading makes their life in prison easier and their time in prison passes faster with books. Only about a quarter of respondents are satisfied with their prison library collection. Almost a fifth of respondents does not visit the library at all because it does not have anything they would like to find there: newspapers, modern literature, non-fiction, reading material for visually impaired and computers.

The purpose of this paper is to investigate the possible application of recycled wool‐based nonwoven material (RWNM) for removal of different dyes that are used in textile dye houses.

The sorption kinetics, the influence of initial dye concentration, pH and temperature are analyzed. Basic, reactive, direct and metal complex dyes are studied.

The sorption properties are highly influenced by the type of the dye owing to differences in their chemical structure and thus, the mechanism of binding to wool. Modification of material with chitosan and hydrogen peroxide improves the sorption capacities and sorption rates but no general trend can be established. Consequently, the sorption behaviour is analyzed separately for each type of the dye.

The results indicate that RWNM can be used as an efficient, low‐cost sorbent for decolorisation of effluents.

This paper aims to show the implementation in the terrestrial trunked radio (TETRA)-based sensor network. The publicly available data show that, in Serbia, the annual damage caused by hailstorms in the past seven years has been estimated almost at an average level of 40m of euros. As the amount of hail was not changed, the hail suppression system of the Republic of Serbia has to be improved, both technically and organizationally, to get better efficiency and protection and to reduce the damage.

In this paper, the authors show the implementation and improvements in the modern terrestrial trunked radio (TETRA)-based sensor network, and they propose the scientific use of sensors for remote control of automatic hail suppression rocket stations.

The authors’ idea is that TETRA should be used as an operational and official telecommunicating system for hail suppression activities units. A number of sensors, connected in a network, are used to maintain a high-quality functioning of this digital radio system, managed remotely and controlled either by operators or automatically.

The presented study with a real example attempts to explain as to how the system functions and how it can improve hail suppression activities.