This thesis presents the design and fabrication of a novel magnetically levitated (maglev) device with six-degree-of-freedom motion capability at nanometer precision. The applications of this device are manufacture of nanoscale structures, assembly of microparts, vibration isolation of delicate instrumentation, and telerobotics. In this thesis, a single-moving stage is levitated by six maglev actuators. The total mass of the moving stage is 0.2126 kg. Three laser interferometers and three capacitance sensors are used to gather the position information. User interface and real-time control routines are implemented digitally on a VME PC and a digital-signal-processor (DSP) board. The underlying mechanical design and fabrication, electrical system setup, control system design, noise analysis, and test results are presented in this thesis. Test results show a quick step response in all six axes and a resolution of 2.5 nm rms in horizontal motion and 25 nm rms in vertical motion.

This thesis presents the design and fabrication of a novel magnetically levitated (maglev) device with six-degree-of-freedom motion capability at nanometer precision. The applications of this device are manufacture of nanoscale structures, assembly of microparts, vibration isolation of delicate instrumentation, and telerobotics. In this thesis, a single-moving stage is levitated by six maglev actuators. The total mass of the moving stage is 0.2126 kg. Three laser interferometers and three capacitance sensors are used to gather the position information. User interface and real-time control routines are implemented digitally on a VME PC and a digital-signal-processor (DSP) board. The underlying mechanical design and fabrication, electrical system setup, control system design, noise analysis, and test results are presented in this thesis. Test results show a quick step response in all six axes and a resolution of 2.5 nm rms in horizontal motion and 25 nm rms in vertical motion.

Modeling process of mechatronics systems. Software used with PLC and simulate real equipment. System has few samples of models with pneumatics elements and model with analog device. There are education materials for students too. Software has been used for education goal at university and kolege.

The rationale behind this research originates from the lack of public health care in South Africa. There is an escalation in the number of stroke victims which is a consequence of the increase in hypertension in this urbanising society. This increase results in a growing need for physiotherapists and occupational therapists in this country which is further hindered by the division between urban and rural areas. The exoskeleton device has been formulated to encapsulate methodologies that enable the anthropomorphic integration between a biological and mechatronic limb. The physiotherapeutic mechanism was designed to be portable and adjustable, without limiting the spherical motion and workspace of the human arm. The exoskeleton was portable in the sense that it could be transported geographically and is a complete device allowing for motion in the shoulder, elbow, wrist and hand joints. The avoidance of singularities in the workspace required the implementation of non-orthogonal joints which produces extensive forward kinematics. Traditional geometric or analytical derivations of the inverse kinematics are complicated by the nonorthogonal layout. This hindrance was resolved iteratively via the Damped Least Squares method. The electronic and computer system allowed for professional personnel, such as an occupational therapist or a physiotherapist, to either change an individual joint or a combination of joints angles. A ramp PI controller was established to provide a smooth response in order to simulate the passive therapy motion. / Thesis (M.Sc.Eng)-University of KwaZulu-Natal, Durban, 2011.

No description available.

Grasp stability was studied and researched upon by various research groups, but mainly focused on robotic grippers by devising conditions for a stable grasp. Maintaining grasp stability is important so as to reduce the chances of the object slipping and dropping. But there was little focus on the grasp stability of robotic exoskeleton gloves and most of the research was focused on mechanical design. A robotic exoskeleton glove was developed as well as novel methods to improve the grasp stability. The exoskeleton glove developed is intended for patients who have suffered paralysis of the hand due to stroke or other factors. The robotic glove aids them in grasping objects as part of daily life activities. The glove is constructed with rigidly coupled 4-bar linkages attached to the finger tips. Each linkage mechanism has 1- Degree of Freedom (DOF) and is actuated by a linear Series Elastic Actuator (SEA). Two methods were developed to satisfy two of the conditions required for a stable grasp. These include deformation prevention of soft objects, and maintaining force and moment equilibrium of the objects being grasped. Simulations were performed to validate the performance of the algorithms. A battery of experiments was performed on the integrated prototype in order to validate the performance of the algorithms developed. / Master of Science / An exoskeleton glove is robotic device that can aid people who suffer from paralysis of their hands caused by a stroke or other factors with the primary goal of allowing them to regain the basic ability of grasping objects and thereby improving their quality of life. The exoskeleton glove developed in this research is focused on objects grasping assistance rather than for rehabilitation purposes. Since the exoskeleton glove lacks conscious senses like a human hand typically possesses, it may not be able to apply sufficient grasping force or may apply excessive force than required irrespective of the object being grasped. In order to ensure that the exoskeleton glove applies the proper amount of force, two novel methods were developed which help improve the overall grasping performance of the robotic glove. These methods use sensors that enable the glove to react to the force interaction changes that exists between the hand and the object being grasped through the exoskeleton glove. The first method detects any deformation that may occur while grasping a soft object and applies lesser force accordingly to prevent further damage to the object. The second method uses motion sensor to detect any movement by the user while grasping the object and applies corrective forces so that the object doesn’t slip from the hand. A prototype was designed and integrated and the two methods were tested on the prototype to validate them.

The work presented in this thesis focuses on the design and testing of a casualty extraction robot intended to stabilize the head and neck of an unresponsive person. The employment of robots in dangerous locales such as combat zones or the site of a natural disaster has the potential to help keep first responders out of harm's way as well as to improve the efficiency of search and rescue teams. After a review of robotic search and rescue platforms the Semi-Autonomous Victim Extraction Robot(SAVER) is introduced. The necessity of a device intended to support the head and cervical spine during transport on a rescue robot is then discussed. The kinematic and dynamic analyses of various candidate differential mechanisms intended for the head stabilization device are described, and the chosen mechanism is demonstrated in a proof-of-concept device. Following testing with a simple PID controller, it was determined an advanced feedback controller with disturbance rejection capabilities was required. Linear Active Disturbance Rejection Control (LADRC) was chosen for its effectiveness in rejecting perturbations and handling modeling uncertainties. The performance the proposed LADRC control scheme was compared with PID in simulation and the results are presented. Finally, a prototype of the device was designed and built to validate the functionality of the subsystem, and the results of the corresponding experimentation are discussed. / M. S. / Robots can help to keep first responders and medics out of dangerous situations by performing the rescue operation themselves or by collaborating with the field medic to make the process quicker and more efficient. The work presented in this thesis begins with a review of state-of-the-art rescue robots followed by the a brief description of the design of a Semi-Autonomous Victim Extraction Robot (SAVER) intended to rescue injured and incapacitated people. After the SAVER system is briefly described, the necessity of a device intended to support the head and cervical spine during transport is discussed. The head stabilization subsystem could also be implemented as a standalone device for use by paramedics to help free up valuable time that would otherwise be spent in manually stabilizing the head and neck of the injured person

<p dir="ltr">A fluid extraction device designed to extract bands of fluid from an ultracentrifuged vial was developed. To do this, a computer vision system was developed to scan the vial and detect the bands and calculate their positions. The computer vision was performed using a TSL1401 DB linescan camera. The vial was scanned by moving the vial vertically in front of the camera using a stepper motor driven linear stage. Pixel data from the line scan camera was analysed to find the edges of each band. This was done by analyzing the first and second derivatives of smoothed pixel data. When the second derivative was 0 and the first derivative was greater than a threshold value, a band edge was detected. Needles were connected to linear actuators and were used to puncture the vials at the desired band's position. After puncturing the vial, fluid was extracted from the vials using a peristaltic pump and placed in a reservoir. Several control architectures were tested an used to control the system. The final control architecture used a LattePanda miniPC to control the system. Several iterations of the fluid extraction device were also created, with the final iteration meeting all the requirements for the device.</p>

Creating flexible and automated production facilities is a complex process that requires high levels of cooperation involving all mechatronics disciplines, where software tools being utilised have to work as closely as their users. Some of these tools are well-integrated but others can hardly exchange any data. This research aims to integrate the software systems applied by the mechatronic engineering disciplines to enable an enhanced design process characterised by a more parallel and iterative work flow. This thesis approaches systems integration from a data modelling point of view because it sees information transfer between heterogeneous data models as a key element of systems integration. A new approach has been developed which is called middle-in data modelling strategy since it is a combination of currently applied top-down and bottom-up approaches. It includes the separation of data into core design data which is modelled top-down and detailed design data modules which are modelled bottom-up. The effectiveness of the integration approach has been demonstrated in a case study undertaken for the mechatronic engineering design process of body shop production lines in the automotive industry. However, the application of the middle-in data modelling strategy is not limited to this use case: it can be used to enhance a variety of system integration tasks. The middle-in data modelling strategy is tested and evaluated in comparison with present top-down and bottom-up data modelling strategies on the basis of three test cases. These test cases simulated how the systems integration solutions based on the different data modelling strategies react to certain disturbances in the data exchange process as they would likely occur during industrial engineering design work. The result is that the top-down data modelling strategy is best in maintaining data integrity and consistency while the bottom-up strategy is most flexibly adaptable to further developments of systems integration solutions. The middle-in strategy combines the advantages of top-down and bottom-up approaches while their weaknesses and disadvantages are kept at a minimum. Hence, it enables the maintenance of data modelling consistency while being responsive to multidisciplinary requirements and adaptive during its step-by-step introduction into an industrial engineering process.

Dans cette thèse nous avons proposé une méthode d’étude des variations paramétriques pour les systèmes mécatroniques continus et hybrides puis une approche du tolérancement mécatronique. Nous avons d’abord étudié les différentes approches existantes pour la prise en compte de la variation de paramètres. Pour les systèmes continus à paramètres variables nous avons choisi la méthode des inclusions différentielles. Nous avons repris l’algorithme de Raczynski et nous avons développé un algorithme d’optimisation qui se base sur la méthode du steepest descent, avec une extension permettant d’obtenir l’optimum global. Pour les systèmes hybrides, contenant des évolutions continues et des sauts discrets, et qui présentent des variations paramétriques, nous avons choisi le formalisme de l’inclusion différentielle impulsionnelle comme outil de modélisation. Nous avons repris ce formalisme et identifié ses éléments sur un système mécatronique. Nous avons développé des algorithmes de résolution des inclusions différentielles impulsionnelles pour un puis pour plusieurs paramètres variables. Pour visualiser les résultats, les algorithmes développés ont été implémentés sous Mathématica. Nous avons fini cette partie par une comparaison entre notre approche et d’autres comme celles autour des automates hybrides à invariant polyèdre, les inclusions différentielles polygonales et l’algorithme pratique de résolution des inclusions différentielles. Nous avons montré alors certains avantages de notre approche. En dernière partie, nous avons repris les différents outils utilisés et résultats obtenus pour définir et affiner notre approche du tolérancement. Nous avons défini la zone du fonctionnement désiré, les différents cas de figures qu’elle peut présenter et son intersection avec le domaine atteignable. Nous avons présenté un outil métrique basé sur la distance topologique de Hausdorff pour le calcul des distances entre ces différents ensembles. Munis de ces éléments, nous avons proposé une démarche itérative pour le tolérancement dans l’espace d’état. / In this thesis we proposed a method for the study of parametric variation for continuous and hybrid systems and an approach for mechatronics tolerancing. We first studied the different existing approaches to take into account the variation of parameters. For continuous systems with variable parameters we chose the method of differential inclusions. We took the Raczynski algorithm and we have developed an optimization algorithm which is based on the steepest descent method with an extension to obtain global optimum. For hybrid systems, containing continuous evolutions and discrete jumps, and have parametric variations, we have chosen the formalism of impulse differential inclusion as a modeling tool. We took this formalism and identified its components on a mechatronic system. We have developed algorithms for solving impulse differential inclusions for several variable parameters. To view the results, the developed algorithms were implemented in Mathematica. We ended this part by a comparison between our approach and others like those around hybrid automata invariant polyhedron, polygonal differential inclusions and practical algorithm for solving differential inclusion. We showed then some advantages of our approach. In the last part, we organized the different tools used and results obtained to define and refine our approach to tolerancing. We defined the area of the desired operation, the various scenarios that may present, and its intersection with reachable area. We presented a metric tool based on topological Hausdorff distance for the calculation of distances between the different sets. With these elements, we proposed an iterative approach to tolerancing in the state space.