Industrial human-robot collaboration: maximizing performance while maintaining safety

The goal of this thesis is to maximize performance in collaborative applications, while maintaining safety. For this, assembly workplaces are analyzed, typical tasks identified, and the potential of collaborative robots is elaborated. Current safety regulations are analyzed in order to identify the challenges in safe human-robot collaboration. Different methods are proposed to solve inefficiency in collaborative applications, in particular, intuitive programming of collaborative robots, efficient control with human-in-the-loop constraints, and a hardware solution, the Robotic Airbag.Das Ziel dieser Arbeit ist die Steigerung der Effizienz in kollaborativen Anwendungen, bei gleichzeitiger Einhaltung der Sicherheitsbestimmungen. Dazu werden Montagearbeitsplätze analysiert und das Potenzial kollaborativer Roboter erarbeitet. Aktuelle Sicherheitsvorschriften werden analysiert, um die Herausforderungen einer sicheren Mensch-Roboter-Zusammenarbeit zu identifizieren. Verschiedene Methoden wie intuitive Programmierung von kollaborativen Robotern, eine effiziente Steuerung mit Human-in-the-Loop Beschränkungen und eine Hardwarelösung - der Robotic Airbag - werden präsentiert

Tarımsal ilaçlamada tüp tipi lineer senkron motor ile püskürtücü yükseklik kontrolü

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Anahtar kelimeler: Tarımsal ilaçlama, püskürtücü yükseklik kontrolü, sabit mıknatıslı tüp tipi lineer senkron motor Tarımsal ilaçlama işleminde, püskürtme yüksekliğini doğru değerde tutmak ilaç sürüklenmesini azaltmakta ve hedef bitki üzerinde eşit dağılımlı ilaç birikimi sağlamaktadır. Bu çalışmada, üçgen hareket profiline sahip sabit mıknatıslı tüp tipi lineer senkron motor (PMTLSM) kullanılarak püskürtücü (nozul) ile bitki arasındaki yüksekliği ayarlayabilen bir tarımsal ilaçlama yükseklik kontrol sistemi geliştirilmiştir. Sistemde, ultrasonik mesafe sensöründen gelen yükseklik bilgisine bağlı olarak, püskürtücü yüksekliği ayarı PMTLSM tarafından gerçekleştirilmektedir. Sistemde ultrasonik sensör iki farklı şekilde konumlandırılmıştır. Birinci yapıda PMTLSM'dan önce ve ikinci yapıda ise motor rotoru ucuna olacak şekilde bir yerleştirme yapılmıştır. Geliştirilen sistem, laboratuvar ortamında ve arazi şartlarında test edilmiştir. Laboratuvar deneyleri, üzerinde yapay bitkiler bulunan konveyör bant sisteminde kimyasal sıvı kullanılmadan yapılmıştır. Deneylerde üç farklı kontrol yöntemi ile PMTLSM'nin altı farklı ivme değeri (2,5, 5, 10, 20, 40, 60 m/s2) ve konveyör bandın dört farklı ilerleme hızı (1, 2, 3, 4 km/h) için püskürtücü yüksekliği, püskürtücü yüksekliği varyasyon katsayısı (CV) değeri ve PMTLSM RMS akım değeri hesaplanmıştır. Arazi deneylerinde aktif püskürtücü kullanılmış ve üç farklı traktör ilerleme hızı (4, 8, 12) için CV değeri, ıslak alan yüzdesi (kaplama oranı) ve ilerleme yönündeki sıvı dağılım düzgünlüğü hesaplanmıştır. Laboratuvar deneylerinde minimum CV ve minimum RMS akım kriterine göre en uygun ivme değeri 20 m/s2 olarak bulunmuştur. Arazi deneylerinden alınan sonuçlara göre, püskürtücü yükseklik kontrolü uygulandığında en yüksek ilerleme hızı 12 km/h için CV değeri %16,77'den %5,17 azalırken, ilerleme yönündeki sıvı dağılım düzgünlüğü %56,57'den %86,11'e yükselmiştir. Geliştirilen sistem, farklı boylardaki bitkiler ile püskürtücü arasındaki mesafeyi test koşulları altında ayarlanan set değerinde minimum hata ile tutmuş ve ilerleme yönündeki sıvı dağılım düzgünlüğünü arttırmıştır.Keywords: Agricultural spraying, nozzle height control, permanent magnet tubular linear synchronous motor In agricultural spraying, keeping the height of the spraying at the correct value reduces pesticide drift and provides uniformly distributed pesticide accumulation on the target plant. In this study, an agricultural nozzle height control test system was developed that can adjust the spraying height between spraying nozzle and the plant using a permanent magnet tubular linear synchronous motor (PMTLSM), which has the triangle motion profile. In the test bench, the nozzle height adjustment is performed by the PMTLSM, depending on the height data from the ultrasonic distance sensor. Ultrasonic sensor has been located in two different position. In the first construction, it has been located before the PMTLSM and in the second construction, it has been located on the rotor of the PMTLSM. The developed system was experimentally tested in the laboratory environment and under field conditions. Laboratory experiments were carried out without the use of chemical fluids in the conveyor belt system with artificial plants. In the experiments, the nozzle height coefficient of variation (CV) and the PMTLSM RMS current value were calculated for six different acceleration values (2.5, 5, 10, 20, 40, 60 m/s2) of PMTLSM and four different speeds (1, 2, 3, 4 km/h) of conveyor belt. In the field tests, the active nozzle was used and the CV value for the three different tractor speed (4, 8, 12), percentage wetted area and the uniformity of distribution in the forward direction was calculated. In the laboratory experiments, the optimum acceleration value according to minimum CV and minimum RMS current criterion was found as 20 m/s2. According to the experimental results, when nozzle height control was applied, the CV value decreased from 16.77% to 5.17%, while the uniformity of distribution in the forward direction increased from 56.57% to 86.11% at 12 km/h under field conditions. Under the test conditions, the developed system has kept the distance between the different sized plants and the nozzle with the minimum error at the set value and also increased the uniformity of distribution in the forward direction

Using the Fringe Field of MRI Scanner for the Navigation of Microguidewires in the Vascular System

Le traitement du cancer, la prévention des accidents vasculaires cérébraux et le diagnostic ou le traitement des maladies vasculaires périphériques sont tous des cas d'application d'interventions à base de cathéter par le biais d'un traitement invasif minimal. Cependant, la pratique du cathétérisme est généralement pratiquée manuellement et dépend fortement de l'expérience et des compétences de l'interventionniste. La robotisation du cathétérisme a été étudiée pour faciliter la procédure en augmentant les niveaux d’autonomie par rapport à cette pratique clinique. En ce qui concerne ce problème, un des problèmes concerne le placement super sélectif du cathéter dans les artères plus étroites nécessitant une miniaturisation de l'instrument cathéter / fil de guidage attaché. Un microguide qui fonctionne dans des vaisseaux sanguins étroits et tortueux subit différentes forces mécaniques telles que le frottement avec la paroi du vaisseau. Ces forces peuvent empêcher la progression de la pointe du fil de guidage dans les vaisseaux. Une méthode proposée consiste à appliquer une force de traction à la pointe du microguide pour diriger et insérer le dispositif tout en poussant l’instrument attaché à partir de l’autre extrémité n’est plus pratique, et à exploiter le gradient du champ de franges IRM surnommé Fringe Field Navigation (FFN ) est proposée comme solution pour assurer cet actionnement. Le concept de FFN repose sur le positionnement d'un patient sur six DOF dans le champ périphérique du scanner IRM afin de permettre un actionnement directionnel pour la navigation du fil-guide. Ce travail rend compte des développements requis pour la mise en oeuvre de la FFN et l’étude du potentiel et des possibilités qu’elle offre au cathétérisme, en veillant au renforcement de l’autonomie. La cartographie du champ de franges d'un scanner IRM 3T est effectuée et la structure du champ de franges en ce qui concerne son uniformité locale est examinée. Une méthode pour la navigation d'un fil de guidage le long d'un chemin vasculaire souhaité basée sur le positionnement robotique du patient à six DOF est développée. Des expériences de FFN guidées par rayons X in vitro et in vivo sur un modèle porcin sont effectuées pour naviguer dans un fil de guidage dans la multibifurcation et les vaisseaux étroits. Une caractéristique unique de FFN est le haut gradient du champ magnétique. Il est démontré in vitro et in vivo que cette force surmonte le problème de l'insertion d'un fil microguide dans des vaisseaux tortueux et étroits pour permettre de faire avancer le fil-guide avec une distale douce au-delà de la limite d'insertion manuelle. La robustesse de FFN contre les erreurs de positionnement du patient est étudiée en relation avec l'uniformité locale dans le champ périphérique. La force élevée du champ magnétique disponible dans le champ de franges IRM peut amener les matériaux magnétiques doux à son état de saturation. Ici, le concept d'utilisation d'un ressort est présenté comme une alternative vi déformable aux aimants permanents solides pour la pointe du fil-guide. La navigation d'un microguide avec une pointe de ressort en structure vasculaire complexe est également réalisée in vitro. L'autonomie de FFN en ce qui concerne la planification d'une procédure avec autonomie de tâche obtenue dans ce travail augmente le potentiel de FFN en automatisant certaines étapes d'une procédure. En conclusion, FFN pour naviguer dans les microguides dans la structure vasculaire complexe avec autonomie pour effectuer le positionnement du patient et contrôler l'insertion du fil de guidage - avec démonstration in vivo dans un modèle porcin - peut être considéré comme un nouvel outil robotique facilitant le cathétérisme vasculaire. tout en aidant à cibler les vaisseaux lointains dans le système vasculaire.----------ABSTRACT Treatment of cancer, prevention of stroke, and diagnosis or treatment of peripheral vascular diseases are all the cases of application of catheter-based interventions through a minimal-invasive treatment. However, performing catheterization is generally practiced manually, and it highly depends on the experience and the skills of the interventionist. Robotization of catheterization has been investigated to facilitate the procedure by increasing the levels of autonomy to this clinical practice. Regarding it, one issue is the super selective placement of the catheter in the narrower arteries that require miniaturization of the tethered catheter/guidewire instrument. A microguidewire that operates in narrow and tortuous blood vessels experiences different mechanical forces like friction with the vessel wall. These forces can prevent the advancement of the tip of the guidewire in the vessels. A proposed method is applying a pulling force at the tip of the microguidewire to steer and insert the device while pushing the tethered instrument from the other end is no longer practical, and exploiting the gradient of the MRI fringe field dubbed as Fringe Field Navigation (FFN) is proposed as a solution to provide this actuation. The concept of FFN is based on six DOF positioning of a patient in the fringe field of the MRI scanner to enable directional actuation for the navigation of the guidewire. This work reports on the required developments for implementing FFN and investigating the potential and the possibilities that FFN introduces to the catheterization, with attention to enhancing the autonomy. Mapping the fringe field of a 3T MRI scanner is performed, and the structure of the fringe field regarding its local uniformity is investigated. A method for the navigation of a guidewire along a desired vascular path based on six DOF robotic patient positioning is developed. In vitro and in vivo x-ray Guided FFN experiments on a swine model of are performed to navigate a guidewire in the multibifurcation and narrow vessels. A unique feature of FFN is the high gradient of the magnetic field. It is demonstrated in vitro and in vivo that this force overcomes the issue of insertion of a microguidewire in tortuous and narrow vessels to enable advancing the guidewire with a soft distal beyond the limit of manual insertion. Robustness of FFN against the error in the positioning of the patient is investigated in relation to the local uniformity in the fringe field. The high strength of the magnetic field available in MRI fringe field can bring soft magnetic materials to its saturation state. Here, the concept of using a spring is introduced as a deformable alternative to solid permanent magnets for the tip of the guidewire. Navigation of a microguidewire with a viii spring tip in complex vascular structure is also performed in vitro. The autonomy of FFN regarding planning a procedure with Task Autonomy achieved in this work enhances the potential of FFN by automatization of certain steps of a procedure. As a conclusion, FFN to navigate microguidewires in the complex vascular structure with autonomy in performing tasks of patient positioning and controlling the insertion of the guidewire – with in vivo demonstration in swine model – can be considered as a novel robotic tool for facilitating the vascular catheterization while helping to target remote vessels in the vascular system

Smooth Trajectory Generation for Machine Tools and Industrial Robots

This thesis presents accurate and time-optimal smooth reference trajectory generation techniques for manufacturing equipment such as high-speed machine tools (MT) and industrial robots (IR). Typical machining tool-paths for MTs and IRs are defined as a series of discrete linear moves. Although Point-to-Point (P2P) feed motion can be generated by interpolating each linear segment with high-order velocity profiles, the continuous and accurate transition between consecutive segments is necessary to realize a non-stop contouring motion for efficient manufacturing. To generate continuous feed motion along sharp cornered tool-paths, most numerical control (NC) systems blend (smooth) corners locally using various curves and splines. The feed (speed) is reduced around the blend sections so that the motion system’s kinematic limits are respected. This thesis proposes 2 novel techniques to enable modern MT and IR to generate non-stop rapid motion along discrete tool-paths. Firstly, a Kinematic Corner Smoothing (KCS) technique has been proposed to generate time-optimal (minimum time) motion trajectories in a real-time within axis kinematic limits. A novel real-time interpolation technique based on Finite Impulse Response (FIR) filtering has also been proposed to suppress residual vibrations for high positioning accuracy of machine tools and motion systems as well. These two techniques are tailored for Cartesian structured motion systems such as 2-3 axis machine tools. Finally, a decoupled FIR filtering technique has been developed to synchronously interpolate tool position and orientation for accurate motion generation for 5-axis MTs and IRs. These techniques are computationally lightweight and suitable for real-time implementation on modern NC systems. Simulation and experimental validation on Cartesian and 5-axis machine tools are presented to validate the effectiveness of the developed algorithms to interpolate along with discrete commands for high-speed and high-accuracy motion