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Uspešno izvođenje pokreta hvatanja predmeta je kod zdravih ljudi zasnovano na prediktivnom planiranju i odgovarajućim korektivnim aktivnostima u slučaju neočekivanih senzornih posledica. Ovi biološki mehanizmi motorne kontrole prisutni su i prilikom upravljanja mioelektričnim protezama, ali su oni u ovom slučaju značajno narušeni. Jedan od razloga za siromašnost ovih mehanizama kod korisnika mioelektričnih proteza je i odsustvo taktilnih povratnih informacijama iz same šake. Glavni cilj ovog istraživanja je stoga bio da se realizuje neinvazivna, veštačka povratna sprega, koristeći vibrotaktilnu stimulaciju kao komunikacioni interfejs, koja olakšava prediktivne i korektivne biološke procese odgovorne za uspešno hvatanje predmeta primenom odgovarajuće sile i da se njena relevantnost ispita prilikom upravljanja protezom u realističnim okolnostima. U tu svrhu, istraživanje je bilo podeljeno u tri faze. U prvoj fazi implementirano je nelinearno mapiranje između upravljačkog, mioelektričnog signala i sile koju veštačka šaka, kada se zatvori, proizvede između prstiju i upoređeno sa konvencionalnim, linearnim mapiranjem. U grupi od 20 ispitanika bez invaliditeta pokazano je da nelinearno mapiranje doprinosi višem procentu uspešnih pokušaja prilikom prediktivnog upravljanja silom hvatanja u poređenju sa linearnim mapiranjem (62.4±16.8% naspram 49.2±17.2%). U sledećoj fazi predstavljena je nova, kombinovana povratna sprega, gde se informacija o intenzitetu mišićne kontrakcije ispitanicima prenosila tokom zatvaranja šake (prediktivno upravljanje), da bi nakon registrovanog kontakta došlo do promene povratne informacije; umesto pomenutog intenziteta mišićne kontrakcije, ispitanicima je u vidu vibrotaktilnih stimulusa prenošena informacija o stvarnoj sili kojom zatvorena šaka deluje na predmet koji drži (korektivno upravljanje). U grupi od 16 ispitanika bez invaliditeta pokazano je da je uspešnost u generisanju željene sile hvatanja prilikom obavljanja jednog funkcionalnog zadat, Successful object grasping in healthy individuals is a combination of predictive motor planning and feedback-driven corrections. These biological mechanisms of human motor control also exist in myoelectric prosthesis users; however, they are substantially disturbed in this group. This is partially due to the lack of tactile sensations from the artificial hand. Therefore, the main goal of this research was to develop a noninvasive, artificial feedback scheme, using a vibrotactile stimulation device as a communication interface, that facilitates both predictive and corrective biological processes responsible for the successful grasping, with the appropriate force, and to assess its relevance in realistic conditions. To this aim, the research was divided into three phases. In the first phase, a nonlinear mapping between the myoelectric control signal and the prosthesis grasping force was implemented and compared to a more conventional, linear mapping. In a group of 20 non-disabled subjects, it was demonstrated that the nonlinear mapping resulted in a higher success rate when predictively controlling the prosthesis grasping force compared to linear mapping (62.4±16.8% versus 49.2±17.2%). In the next phase, a novel, combined feedback scheme was introduced, where the intensity of muscle contraction was conveyed to the subjects while closing the prosthesis (predictive control), whereas after the contact, the feedback switched and the vibrotactile stimuli started transmitting the information about the actual grasping force (corrective control). A group of 16 non-disabled subjects performing a functional task achieved the highest success rate in generating the desired grasping force when using the combined feedback (79.6±9.9%), whereas the success rate was the lowest when the vibrotactile stimulation was completely turned off (53±11.5%). The aim of the final phase of this research was to demonstrate the clinical translation of the proposed closed-loop control of a myoelectri

Na osnovu potreba razvoja i istraživanja visokobrzinskih motor-vretena, može se zaključiti da je neophodan kompleksan pristup ovom sklopu kao složenom mehaničkom sistemu, koji direktno utiče na ponašanje mašine alatke u eksploataciji. Kompleksan pristup treba da omogući da se toplotno-mehaničko ponašanje mašina alatki predvidi još u fazi projektovanja. Kako su glavna vretena sa visokobrzinskim kotrljajnim ležištima još uvek najzastupljenija konstrukciona rešenja, to je pred ovaj rad postavljen zadatak da se motor-vreteno, analizira sa stanovišta toplotno-mehaničkog ponašanja, te da se kreira kompleksan toplotno-mehanički model sklopa motor-vretena. Na primeru sklopa visokobrzinskog motor-vretena, uležištenog kugličnim ležajima sa kosim dodirom, želi se eksperimentalnim ispitivanjem proveriti definisani model za identifikaciju toplotno-mehaničkog ponašanja i analizirati uticaj temperature na njegove statičke i dinamičke karakteristike. Takođe se kroz rad analiziraju uticaji različitih fluida za hlađenje motor-vretena, kao i uticaj količine protoka fluida kako za hlađenje statora, tako i za hlađenje i podmazivanje ležaja. Polazeći od ovako definisanog globalnog zadatka, istraživanja u radu su izložena u okviru devet poglavlja., Based on the needs of development and research of high-speed motor-spindles, it can be concluded that a complex approach to this assembly is necessary as a complex mechanical system, which directly affects the behavior of the machine tool in exploitation. A complex approach should enable the thermal-mechanical behavior of machine tools to be predicted at the design stage. As the main spindles with high-speed rolling bearings are still the most represented construction solutions, the task of this work is to analyze the motor-spindle from the point of view of thermal-mechanical behavior, and to create a complex thermal-mechanical model of the motor-spindle assembly. On the example of a high-speed motor-spindle assembly, supported by ball bearings with oblique contact, it is desired to verify the defined model for the identification of thermal-mechanical behavior and analyze the influence of temperature on its static and dynamic characteristics through experimental testing. The work also analyzes the influence of different fluids for cooling the motor-spindle, as well as the influence of the amount of fluid flow both for cooling the stator and for cooling and lubricating the bearings. Starting from the global task defined in this way, the research in the paper is presented in nine chapters.