FEEDBACK LINEARIZATION FOR DECOUPLED POSITION/STIFFNESS CONTROL OF BIDIRECTIONAL ANTAGONISTIC DRIVES

To ensure safe human-robot interaction impedance robot control has arisen as one of the key challenges in robotics. This paper elaborates control of bidirectional antagonistic drives – qbmove maker pro. Due to its mechanical structure, both position and stiffness of bidirectional antagonistic drives could be controlled independently. To that end, we applied feedback linearization. Feedback linearization based approach initially decouples systems in two linear single-input-single-output subsystems: position subsystem and stiffness subsystem. The paper elaborates preconditions for feedback linearization and its implementation. The paper presents simulation results that prove the concept but points out application issues due to the complex mechanical structure of the bidirectional antagonistic drives

Lobular panniculitis: A manifestation of pancreatic tumor with fatal outcome

Lobular panniculitis is a skin condition that may be the first sign of underlying pancreatic disease. Though rare, the condition has been sufficiently well defined and pathognomonic, thus making differentiation from idiopathic lobular panniculitis quite possible. A 77-year-old woman was in apparently good general health condition when developed skin lesions in a form of erythematous painful fluctuant nodules localized predominantly on the breast, but also present on the arms, thighs, and trunk. Her serum and urinary amylase levels were respectively 3 and 8 fold higher than normal. On histology, skin biopsy showed acute lobular panniculitis with large foci of adipocyte necrosis. Examination of the breast excluded any specific process other than nodular subcutaneous inflammation, but revealed a tumor of the pancreatic head. The nodules spontaneously ulcerated exuding an oily thick brownish material. Her condition deteriorated, and she became progressively debilitated. The patient died before operation, within the next 3 weeks. Subcutaneous fat necrosis was the first manifestation of an otherwise occult pancreatic disease with fatal outcome

Virtual laboratories for education in science, technology, and engineering: A review

Within education, concepts such as distance learning, and open universities, are now becoming more widely used for teaching and learning. However, due to the nature of the subject domain, the teaching of Science, Technology, and Engineering are still relatively behind when using new technological approaches (particularly for online distance learning). The reason for this discrepancy lies in the fact that these fields often require laboratory exercises to provide effective skill acquisition and hands-on experience. Often it is difficult to make these laboratories accessible for online access. Either the real lab needs to be enabled for remote access or it needs to be replicated as a fully software-based virtual lab. We argue for the latter concept since it offers some advantages over remotely controlled real labs, which will be elaborated further in this paper. We are now seeing new emerging technologies that can overcome some of the potential difficulties in this area. These include: computer graphics, augmented reality, computational dynamics, and virtual worlds. This paper summarizes the state of the art in virtual laboratories and virtual worlds in the fields of science, technology, and engineering. The main research activity in these fields is discussed but special emphasis is put on the field of robotics due to the maturity of this area within the virtual-education community. This is not a coincidence; starting from its widely multidisciplinary character, robotics is a perfect example where all the other fields of engineering and physics can contribute. Thus, the use of virtual labs for other scientific and non-robotic engineering uses can be seen to share many of the same learning processes. This can include supporting the introduction of new concepts as part of learning about science and technology, and introducing more general engineering knowledge, through to supporting more constructive (and collaborative) education and training activities in a more complex engineering topic such as robotics. The objective of this paper is to outline this problem space in more detail and to create a valuable source of information that can help to define the starting position for future research

Results on the usage of UAV in chemical plant protection

he usage of UAV - Unmanned Aircraft Vehicle in the precision agriculture creates numerous opportunities for detecting and informing farm ers about the current state of cultivated crops, and the quality of the imple mentation of certain agro-technical operations during production. In recent years, UAV have been used in chemical plant protection, in the application of mineral fertilizers, in the detection of pests, diseases, and other aspects of ag ricultural production. The importance of the usage of UAV in agricultural production is becoming bigger and more significant, which could, in the long term, affect the more efficient and productive agricultural production, with a significant reduction in the consumption of the inputs of production. This study describes two types of UAV used in the chemical plant protec tion, which were analyzed according to the technical characteristics of the UAV, as well as the precision of the spray coverage of the protective liquid. The precision of distribution of the protective liquid is monitored at differ ent ground speeds and heights during chemical protection. The MG-1 model UAV achieves the best quality of the application of protective liquid at a flight groundspeed of 3 ms-1 (largest effective swath of 6.8 m) and a flying height of 2 m (largest effective swath of 7.3 m). The V6A model UAV achieves the best application quality of the protective liquids at a flight groundspeed of 7 ms-1 (largest effective swath of 5.8 m), and at a flying height of 2 m (largest effective swath of 5.6 m). The results of the UAV analyzed showed that the uniformity of the application of the protective liquid directly de pends on the model of the UAV and its technical characteristics

Mоделирањe и управљањe антропомиметичког робота са антагонистичким погонима у контактним и бесконтактним задацима

The thesis considers a very popular and rapidly growing topic in robotics – modeling and control of anthropomimetic robots, in particular robots that feature compliant antagonistic actuation. The term ‘anthropomimetic’ refers to a robot of fully human-like appearance, but also human-like inner structure and functionality. The motivation for the thesis came from the involvement of the author and the School of Electrical Engineering, University of Belgrade in the project Eccerobot (Embodied Cognition in a Compliantly Engineered Robot), funded by European 7th Framework Programme, and the project Ambient Intelligent Service Robots of Anthropomorphic Characteristics funded by Serbian Ministry of Education, Science and Technological Development. Since conventional rigid actuators have become obsolete for inherently-safe future robotic applications, the design and control of novel compliant actuators have recently been under intensive investigation. In particular, variable stiffness (impedance) actuators (VSAs), which can trade-off between robot trajectory tracking and overall safety, are the focus of robotics research. We focus on antagonistically-driven joints, as a subgroup of bio-inspired VSAs. The thesis is organized in six sections and bibliography. The first section outlines the main ideas and motivation for the work. It presents research directions, points of view and initiatives in the design and control of compliant robots, with special emphasis on antagonistic drives. It also addresses safety issues of future service robots, and lists technologies, trends, and approaches towards achieving that goal: moving from stiff to compliant actuators, the benefits introduced by passive and active compliance, VSA, etc. As a special group of bio-inspired VSAs in robotics, antagonistic actuators are reviewed comprehensively. Such a detailed review of antagonistic actuator design aims to highlight the importance of the subject, on the one hand, while on the other hand it presents the technology that will be intensively exploited in future anthropomimetic robots...У тези је обрађена врло актуелна тема у области роботике - моделирање и управљање антропомиметичким роботима, посебно оним са еластичним антагонистичким погонима. Појам антропомиметички се односи на робота који подсећа на човека не само својим изгледом, већ и унутрашњом структуром и функционалношћу. Мотивација за израду ове дисертације је произишла из активности аутора на Електротехничком факултету у Београду, а у оквиру пројекта Eccerobot - Embodied Cognition in a Compliantly Engineered Robot, финансираног од стране седмог оквирног програма Европске уније и пројекта „Амбијентално интелигентни сервисни робота антропоморфних карактеристика“, финансираног од стране Министартва за просвету, науку и технолошки развој Републике Србије. С обзиром на недостатке конвенционалних крутих актуатора у будућим роботским апликацијама које захтевају висок степен безбедности, развој и управљање нових актуатора који укључују еластичност је од великог значаја. Посебно је значајан развој актуатора са променљивом крутошћу VSA (од енглеског назива “variable stiffness actuator”) који омогућавају подешавање крутосту током рада и самим тим дају компромис између прецизности рада робота и безбедности његовог окружења. Фокус нашег истраживања су роботи са антагонистичким погонима као посебна група билошки инспирисаних VSA. Дисертација је организована у шест поглавља уз преглед литературе. У првом поглављу су истакнуте главне идеје и мотивација за рад на овој теми, као и правци истраживања у развоју и управљању зглобова са еластичношћу, са нагласком на антагонистичке погоне. У овом поглављу се истичу безбедносни изазови будућих сервисних робота, наводе се одговарајуће технологије и трендови: еластични актуатори, појмови активне и пасивне попустљивости и VSA. Као група од посебног интереса међу VSA, приказан је детаљан пресек стања на тему антагонистичких актуатора у роботици. Развој симулационог модела динамике робота погоњеног антагонистички упареним еластичним актуаторима је детаљно приказан у другом поглављу дисертације. У том циљу, искоришћен је Степањенков метод за моделирање..

Mоделирањe и управљањe антропомиметичког робота са антагонистичким погонима у контактним и бесконтактним задацима

The thesis considers a very popular and rapidly growing topic in robotics – modeling and control of anthropomimetic robots, in particular robots that feature compliant antagonistic actuation. The term ‘anthropomimetic’ refers to a robot of fully human-like appearance, but also human-like inner structure and functionality. The motivation for the thesis came from the involvement of the author and the School of Electrical Engineering, University of Belgrade in the project Eccerobot (Embodied Cognition in a Compliantly Engineered Robot), funded by European 7th Framework Programme, and the project Ambient Intelligent Service Robots of Anthropomorphic Characteristics funded by Serbian Ministry of Education, Science and Technological Development. Since conventional rigid actuators have become obsolete for inherently-safe future robotic applications, the design and control of novel compliant actuators have recently been under intensive investigation. In particular, variable stiffness (impedance) actuators (VSAs), which can trade-off between robot trajectory tracking and overall safety, are the focus of robotics research. We focus on antagonistically-driven joints, as a subgroup of bio-inspired VSAs. The thesis is organized in six sections and bibliography. The first section outlines the main ideas and motivation for the work. It presents research directions, points of view and initiatives in the design and control of compliant robots, with special emphasis on antagonistic drives. It also addresses safety issues of future service robots, and lists technologies, trends, and approaches towards achieving that goal: moving from stiff to compliant actuators, the benefits introduced by passive and active compliance, VSA, etc. As a special group of bio-inspired VSAs in robotics, antagonistic actuators are reviewed comprehensively. Such a detailed review of antagonistic actuator design aims to highlight the importance of the subject, on the one hand, while on the other hand it presents the technology that will be intensively exploited in future anthropomimetic robots...У тези је обрађена врло актуелна тема у области роботике - моделирање и управљање антропомиметичким роботима, посебно оним са еластичним антагонистичким погонима. Појам антропомиметички се односи на робота који подсећа на човека не само својим изгледом, већ и унутрашњом структуром и функционалношћу. Мотивација за израду ове дисертације је произишла из активности аутора на Електротехничком факултету у Београду, а у оквиру пројекта Eccerobot - Embodied Cognition in a Compliantly Engineered Robot, финансираног од стране седмог оквирног програма Европске уније и пројекта „Амбијентално интелигентни сервисни робота антропоморфних карактеристика“, финансираног од стране Министартва за просвету, науку и технолошки развој Републике Србије. С обзиром на недостатке конвенционалних крутих актуатора у будућим роботским апликацијама које захтевају висок степен безбедности, развој и управљање нових актуатора који укључују еластичност је од великог значаја. Посебно је значајан развој актуатора са променљивом крутошћу VSA (од енглеског назива “variable stiffness actuator”) који омогућавају подешавање крутосту током рада и самим тим дају компромис између прецизности рада робота и безбедности његовог окружења. Фокус нашег истраживања су роботи са антагонистичким погонима као посебна група билошки инспирисаних VSA. Дисертација је организована у шест поглавља уз преглед литературе. У првом поглављу су истакнуте главне идеје и мотивација за рад на овој теми, као и правци истраживања у развоју и управљању зглобова са еластичношћу, са нагласком на антагонистичке погоне. У овом поглављу се истичу безбедносни изазови будућих сервисних робота, наводе се одговарајуће технологије и трендови: еластични актуатори, појмови активне и пасивне попустљивости и VSA. Као група од посебног интереса међу VSA, приказан је детаљан пресек стања на тему антагонистичких актуатора у роботици. Развој симулационог модела динамике робота погоњеног антагонистички упареним еластичним актуаторима је детаљно приказан у другом поглављу дисертације. У том циљу, искоришћен је Степањенков метод за моделирање..

Mоделирањe и управљањe антропомиметичког робота са антагонистичким погонима у контактним и бесконтактним задацима

The thesis considers a very popular and rapidly growing topic in robotics – modeling and control of anthropomimetic robots, in particular robots that feature compliant antagonistic actuation. The term ‘anthropomimetic’ refers to a robot of fully human-like appearance, but also human-like inner structure and functionality. The motivation for the thesis came from the involvement of the author and the School of Electrical Engineering, University of Belgrade in the project Eccerobot (Embodied Cognition in a Compliantly Engineered Robot), funded by European 7th Framework Programme, and the project Ambient Intelligent Service Robots of Anthropomorphic Characteristics funded by Serbian Ministry of Education, Science and Technological Development. Since conventional rigid actuators have become obsolete for inherently-safe future robotic applications, the design and control of novel compliant actuators have recently been under intensive investigation. In particular, variable stiffness (impedance) actuators (VSAs), which can trade-off between robot trajectory tracking and overall safety, are the focus of robotics research. We focus on antagonistically-driven joints, as a subgroup of bio-inspired VSAs. The thesis is organized in six sections and bibliography. The first section outlines the main ideas and motivation for the work. It presents research directions, points of view and initiatives in the design and control of compliant robots, with special emphasis on antagonistic drives. It also addresses safety issues of future service robots, and lists technologies, trends, and approaches towards achieving that goal: moving from stiff to compliant actuators, the benefits introduced by passive and active compliance, VSA, etc. As a special group of bio-inspired VSAs in robotics, antagonistic actuators are reviewed comprehensively. Such a detailed review of antagonistic actuator design aims to highlight the importance of the subject, on the one hand, while on the other hand it presents the technology that will be intensively exploited in future anthropomimetic robots...У тези је обрађена врло актуелна тема у области роботике - моделирање и управљање антропомиметичким роботима, посебно оним са еластичним антагонистичким погонима. Појам антропомиметички се односи на робота који подсећа на човека не само својим изгледом, већ и унутрашњом структуром и функционалношћу. Мотивација за израду ове дисертације је произишла из активности аутора на Електротехничком факултету у Београду, а у оквиру пројекта Eccerobot - Embodied Cognition in a Compliantly Engineered Robot, финансираног од стране седмог оквирног програма Европске уније и пројекта „Амбијентално интелигентни сервисни робота антропоморфних карактеристика“, финансираног од стране Министартва за просвету, науку и технолошки развој Републике Србије. С обзиром на недостатке конвенционалних крутих актуатора у будућим роботским апликацијама које захтевају висок степен безбедности, развој и управљање нових актуатора који укључују еластичност је од великог значаја. Посебно је значајан развој актуатора са променљивом крутошћу VSA (од енглеског назива “variable stiffness actuator”) који омогућавају подешавање крутосту током рада и самим тим дају компромис између прецизности рада робота и безбедности његовог окружења. Фокус нашег истраживања су роботи са антагонистичким погонима као посебна група билошки инспирисаних VSA. Дисертација је организована у шест поглавља уз преглед литературе. У првом поглављу су истакнуте главне идеје и мотивација за рад на овој теми, као и правци истраживања у развоју и управљању зглобова са еластичношћу, са нагласком на антагонистичке погоне. У овом поглављу се истичу безбедносни изазови будућих сервисних робота, наводе се одговарајуће технологије и трендови: еластични актуатори, појмови активне и пасивне попустљивости и VSA. Као група од посебног интереса међу VSA, приказан је детаљан пресек стања на тему антагонистичких актуатора у роботици. Развој симулационог модела динамике робота погоњеног антагонистички упареним еластичним актуаторима је детаљно приказан у другом поглављу дисертације. У том циљу, искоришћен је Степањенков метод за моделирање..

Hill’s and Huxley’s muscle models - tools for simulations in biomechanics

Numerous mathematical models of human skeletal muscles have been developed. However, none of them is adopted as a general one and each of them is suggested for some specific purpose. This topic is essential in humanoid robotics, since we firstly need to understand how human moves and acts in order to exploit human movement patterns in robotics and design human like actuators. Simulations in biomechanics are intensively used in research of locomotion, safe human-robot interaction, development of novel robotic actuators, biologically inspired control algorithms, etc. This paper presents two widely adopted muscle models (Hill’s and Huxley’s model), elaborates their features and demonstrates trade-off between their accuracy and efficiency of computer simulations. The simulation setup contains mathematical representation of passive muscle structures as well as mathematical model of an elastic tendon as a series elastic actuation element. Advanced robot control techniques point out energy consumption as one of the key issues. Therefore, energy store and release mechanism in elastic elements in both tendon and muscle, based on the simulation models, are considered. [Projekat Ministarstva nauke Republike Srbije, br. TR35003 and br. OS175016

Automated Sound Intensity Measuremant With Robot And Intensity Probe

This paper presents the procedure for measuring the sound intensity. The procedure was realized in such a way that therobotic arm carries the intensity probe and performs automatic positioning at the appropriate measurement points. In order todetermine the deviation value, a comparison was performed of sound intensity measurement obtained using robot and the measurementmanually performed by two people. Also, the measurement process was repeated for both the automated and manual positioning of theprobe, which resulted in deviation values for these two types of measurements. The differences in the total sound power of the sourceobtained by automated and manual measurements of the sound intensity were also analyzed. Using a robot arm significantly facilitatesthe measurement process and achieves higher measurement accuracy. Such use of robots can be of interest in measuring the intensity ofsound of complex sound sources in a large number of points, where high accuracy of intensity measurement is required