The objective of this thesis is the algorithmic enhancement and initial evaluation of an underwater acoustic positioning system which is designed to determine the position and orientation of a mobile nuclear reactor vessel inspection robot. Although a great deal of research has been done in the area of underwater acoustic positioning, this work differs from previous work in three significant ways. First, most applied acoustic positioning systems have been designed for the offshore oil drilling industry, and thus their requirements and restrictions are dictated by an oceanic environment. Second, most previous work has focused only upon acquiring the position of a point from the acoustic system. The inspection robot operation requires accurate positioning and orientation. Finally, the accuracy of acoustic positioning systems is generally dependent upon an evaluation of the speed of sound. However, this parameter is highly dependent upon water temperature. As will be discussed, the reactor vessel water temperature may not be uniform or constant, which makes the design of a precise positioning system difficult. Original methods to overcome this obstacle are discussed and evaluated. Also examined are configurations and constraints of the acoustic transceivers, the numerical solution procedures utilized, and the resulting errors associated with the developed methods. / Master of Science

In order for robots to become more useful they must be able to adapt and operate in foreign or unpredictable environments. The goal of this thesis is to present an algorithm that will enable a robot to autonomously explore its environment by touch and then estimate the shape of objects it encounters. To demonstrate the feasibility and functionality of such an algorithm, it was fully implemented on a MERLIN 6540 industrial robot. A unique compliant end-effector (consisting of a trackball mounted to a force/torque sensor on a sliding mechanism) and a fuzzy logic force controller were developed to overcome the difficulties inherent in force control on a stepper motor robot. A Kalman filter based quadric shape estimator was then used to describe the objects encountered in the MERLIN's workspace. The minimization of a cost function based on the shape estimator's uncertainty guided the robot along an exploration trajectory designed to produce the fastest converging shape estimate. Results of various exploration trials using autonomous and preprogrammed trajectories are presented. In addition to shape estimates, surface curvature measurements were also obtained. The unique end-effector that provided compliance for the force controller was also able to measure the arc length traversed on the object's surface. Arc length combined with surface orientation makes it possible to determine local surface curvature. / Master of Science

In poultry plants in the United States, a water chiller is used to chill WOGs (de-feathered birds without giblets). After exiting the chiller these birds are manually transferred from a conveyor belt to shackles for further processing. The current process is less than ideal. The labor pool for jobs such as these is continuing to shrink and labor turnover is a constant problem. The rates of repetitive motion injury reported are high and are continuing to rise. In addition, many poultry producers see this as a bottleneck in the process. Automation has the potential to alleviate these problems. The high variability of this task, cost restrictions, and special design considerations associated with meat handling equipment make automation of this task challenging. Industrial robots have traditionally been limited to tasks with low variability. This task has high variability. They are presented on the conveyor belt in a wide variety of positions and orientations. Most robotic automation systems consist of a commercially available industrial robot, a specialized end effector and a control scheme. The economics of this task prohibit the use of a commercially available industrial robot, as there are no industrial robots on the market that will offer a short enough payback. Robots have not yet been adapted to meat handling processes, and existing robotic designs are not well suited to the task. In designing a low cost, high-speed robot for poultry processing the requirements of the robot are defined and a variety of robot architectures, constructions, and materials are explored. Simple modifications to the existing shackle and conveyor setup to make the task easier for a robot are also explored. After the robot requirements are defined a large group of possible designs are developed. The possible designs are systematically evaluated and/or eliminated until a single design is selected. The forward and reverse kinematics for this robot are developed. A singularity analysis is carried out. A proof of concept model is built. A prototype is modeled and a dynamic analysis of that prototype is carried out. The design is finalized based on the results of the dynamic analysis.

At a platform singularity, a parallel manipulator loses constraint. Adding redundant actuation in an existing leg or new leg can eliminate these types of singularities. However, redundant manipulators have been designed with little attention to frame invariant techniques. In this dissertation, physically meaningful measures for closeness to singularities in non-redundant manipulators are developed. Two such frameworks are constructed. The first framework is a constrained optimization problem that unifies seemingly unrelated existing measures and facilitates development of new measures. The second is a clearance propagation technique based on workspace generation. These closeness measures are expanded to include redundancy and thus can be used as objective functions for designing redundant actuation. The constrained optimization framework is applied to a planar three degree of freedom redundant parallel manipulator to show feasibility of the technique.

A study was conducted to set up an automated system for the use of industrial robots in frequently changing palletizing applications. The system consists of an industrial robot (IBM Manufacturing System 7545), an IBM PC, a gripper carousel storage system, a quick-change mechanism, and a robot gripper. The system is set up to enable a minimum of operator intervention. Hardware aspects (quick-change mechanism and gripper storage) as well as dynamic software generation for different palletizing applications were considered in the research project. The research effort involved both software and hardware developments. A FORTRAN program was developed to generate pallet patterns based on dynamic input of package and platform parameters. The geometric pattern was then used to create an appropriate AML/E program to drive the robot through the desired motion sequence. This program was then compiled and downloaded to the robot. Hardware aspects of the research were focused on the development of a system to permit dynamic changing of end of arm tooling. This included the development of a quick-change mechanism and a gripper carousel storage system. The quick-change mechanism included interfaces for electronic signals, air, and vacuum lines. A vacuum gripper was also designed for package handling. / M.S.

Le soudage par friction malaxage (FSW) est un procédé de soudage innovant pour les matériaux à bas point de fusion (aluminium, cuivre…). Il a été breveté en 1992 par l’organisme anglais The Welding Institute (TWI). Depuis plusieurs années, celui-ci se développe dans l’industrie en cherchant à réduire son coût d’investissement. Le principe du FSW est de réaliser un cordon de soudure grâce à un outil animé d’un mouvement de rotation et d’avance. Les niveaux d’efforts et de précision requis contraignent à l’utilisation de machines cartésiennes de grande envergure. L’utilisation des robots industriels est un moyen de réduire les coûts, mais ils ne sont pas conçus pour ce genre d’applications et leur inconvénient majeur réside dans leur manque de rigidité. Ainsi, lorsque l’outil entre en contact avec les pièces à assembler, celui-ci peut dévier de plusieurs millimètres dans différentes directions de l’espace, rendant la mise en oeuvre d’une compensation de la trajectoire du robot obligatoire afin d’obtenir des soudures sans défauts. Le but de cette thèse a été de développer un procédé robotisé robuste. Le premier objectif est la mise en oeuvre d’une commande en effort robuste. En effet, en FSW, le maintien d’un effort axial constant est obligatoire. Le contrôle de cet effort permet de compenser la déviation axiale de l’outil et les défauts de mise en position des pièces à souder. Ainsi, une démarche d’identification et de modélisation afin de créer une commande en effort a été mise en oeuvre. La commande est définie de manière robuste afin d’éviter les réglages de l’asservissement lorsque les outils, les paramètres de soudage ou les trajectoires du robot changent. Une validation expérimentale complète a été réalisée dans le contexte du FSW. Le second objectif de cette thèse a été de développer une compensation de la déviation latérale de l’outil. Contrairement à l’objectif précédent, il n’y a pas d’effort à maintenir pour compenser cette déviation latérale. Dans l’industrie, cette déviation peut être compensée à l’aide d’un système de vision, mais ce dernier comporte de nombreux inconvénients en FSW (réflexion de l’aluminium, non visibilité du joint, coût, mise en oeuvre complexe). Ainsi, dans cette partie, un algorithme de compensation temps réel de la déviation latérale de l’outil a été mis en oeuvre. Celui-ci repose sur l’identification d’un modèle élasto-statique du robot. L’algorithme de compensation de la déviation latérale de l’outil a été couplé à la commande en effort et validé expérimentalement en FSW. La différence avec la majorité des travaux de recherche dans ce domaine est que les procédures d’identification n’utilisent pas de système de mesure 3D (photogrammétrie CCD ou laser de poursuite) dont le coût est un frein indéniable pour beaucoup d’industriels. La démarche est simple à mettre en oeuvre sur un robot industriel du marché actuel, et applicable pour d’autres procédés à contact comme l’usinage ou le polissage. / Friction Stir Welding (FSW) is an innovative welding process for materials with a low melting point (aluminium, copper…). It was patented in 1992 by the English organization The Welding Institute (TWI). For many years, an effort is done to reduce the investment cost for industrial applications. FSW process involves a rotating tool advancing along a path. Currently, gantry-type CNC systems are using for FSW manufacturing. These machines offer a high stiffness and can tolerate the forces during FSW in order to carry out a good weld quality. Industrials robots can reduce the investment cost; however they are not design for these applications. The main limitation is the low stiffness of the robot structure. Consequently, the robot deformation under the high process forces causes tool deviations about several millimeters. The robot path has to be compensated in order to obtain a good weld quality. The aim of this thesis is to develop a robust robotized process. The first goal is to realize a robust force control. During FSW, a constant axial forging force should be applied. Axial tool deviation is compensated with the force control approach. In this way, a modeling and identification method is done in order to design a force controller. The force controller is robust because no tuning is required, even if welding parameters or robot paths change. An experimental validation in FSW is done. The second goal is to realize a compensation of the lateral tool deviation. Unlike the axial deformation, there is no force to maintain for compensate this deviation. In industry, the lateral tool deviation could be compensated with a camera or laser sensor in order to track the weld seam path during welding. However, the cost of a seam tracking device, the aluminium reflexion and the lack of visibility in lap joint configuration are significant drawbacks. In this chapter, a compensation algorithm is designed. An elastostatic model of the robot is used to estimate in real time the deflection of the robot TCP. The compensation algorithm is coupled with the force controller defined previously. Compare with others research works about this topic, identification methods don’t need a 3D measurement system (CCD camera or laser tracker). The cost of such system is a main drawback for industrial applications. In this thesis, identification methods are easy to implement in an industrial robot and available for others processes like machining or polishing.

Motion planning for redundant manipulators poses special challenges because the required inverse kinematics are difficult and not complete. This thesis investigates and proposes methods for motion planning for these systems that do not require inverse kinematics and are potentially complete. These methods are also compared in performance to standard inverse kinematics based methods.

This thesis is motivated by practical problems encountered in handling live products in the poultry processing industry, where live birds are manually transferred by human labors. As the task of handling live products is often unpleasant and hazardous, it is an ideal candidate for automation. To reduce the number of configurations and live birds to be tested, this thesis focuses on developing analytical models based on the Lagrange method to predict the effect of mechanical inversion on the shackled bird. Unlike prior research which focused on the effect of different inversion paths on the joint force/torque of a free-falling shackled bird, this thesis research examines the effect of kinematic constraints (designed to support the bird body) on the shackled bird. Unlike free-falling, the imposed kinematic constraints enable the shackled bird to rotate about its center of mass, and thus minimize wing flapping. In this thesis, birds are geometrically approximated as ellipsoids while the lower extremity is modeled as a pair of multi-joint serial manipulators. With the constraint equations formulated into a set of differential algebraic equations, the equations of motion as well as Lagrange multipliers characterizing kinematical constraints are numerically solved for the bird motion, specifically the position, velocity, and orientation and hence the forces and torques of the joints. The dynamic models are verified by comparing simulation results against those obtained using a finite element method. The outcomes of this thesis will provide some intuitive insights essential to design optimization of a live-bird transfer system.

Ursprünglich wurden Industrieroboter hauptsächlich hinter Schutzzäunen betrieben, um den Sicherheitsanforderungen gerecht zu werden. Mit der Flexibilisierung der Produktion wurden diese scharfen Trennbereiche zunehmend aufgeweicht und externe Sicherheitstechnik, wie Abstandssensoren, genutzt, um Industrieroboter schutzzaunlos zu betreiben. Ausgehend vom Gedanken dieser Koexistenz bzw. Kooperation wurde die Sicherheitssensorik in den Roboter integriert, um eine wirkliche Kollaboration zu ermöglichen. Diese sogenannten kollaborierenden Roboter, oder Cobots, eröffnen neue Applikationsfelder und füllen somit die bestehenden Automatisierungslücken. Doch welche Automatisierungsvariante ist aus wirtschaftlichen Gesichtspunkten die geeignetste? Bisherige Forschung untersucht zum Großteil isoliert eine der beiden Technologien, ohne dabei einen Systemvergleich hinsichtlich technologischer Spezifika und Wirtschaftlichkeit anzustellen. Daher widmet sich diese Dissertation einer Methodik zum wirtschaftlichen Vergleich von kollaborierenden Robotern und Industrierobotern in schutzzaunlosen Maschinenbeladungssystemen. Besonderer Fokus liegt dabei auf dem Herausarbeiten der technischen Faktoren, die die Wirtschaftlichkeit maßgeblich beeinflussen, um ein Systemverständnis der wirtschaftlichen Struktur beider Robotertechnologievarianten zu erhalten. Zur Untersuchung werden die Inhalte eines solchen Planungsvorhabens beschrieben, kategorisiert, systematisiert und modularisiert. Auf wirtschaftlicher Seite wird ein geeignetes Optimierungsmodell vorgestellt, während auf technischer Seite vor allem die Machbarkeit hinsichtlich Greifbarkeit, Layoutplanung, Robotergeschwindigkeiten und Zykluszeitbestimmung untersucht wird. Mit deduktiven, simulativen, empirischen und statistischen Methoden wird das Systemverhalten für die einzelnen Planungsinhalte analysiert, um die Gesamtwirtschaftlichkeit mit einem Minimum an Investment,- Produktions,- und Zykluszeitinformationen a priori vorhersagen zu können. Es wird gezeigt, dass durch einen Reverse Engineering Ansatz die notwendigen Planungsdaten, im Sinne von Layoutkomposition, Robotergeschwindigkeiten und Taktzeiten, mithilfe von Frontloading zu Planungsbeginn zur Verfügung gestellt werden können. Dabei dient der Kapitalwert als wirtschaftliche Bewertungsgrundlage, dessen Abhängigkeit vom Mensch-Roboter-Interaktionsgrad in einem Vorteilhaftigkeitsdiagramm für die einzelnen Technologiealternativen dargestellt werden kann. Wirtschaftlich fundierte Entscheidungen können somit auf quantitiativer Basis getroffen werden.:1. Introduction 25 1.1 Research Domain 25 1.2 Research Niche 26 1.3 Research Structure 28 2. State of the Art and Research 31 2.1 Turning Machines and Machine Tending 31 2.1.1 Tooling Machine Market Trends and Machine Tending Systems 31 2.1.2 Workpiece System 34 2.1.3 Machine System 36 2.1.4 Logistics System 39 2.1.5 Handling System 41 2.2 Robotics 43 2.2.1 Robot Installation Development and Application Fields 43 2.2.2 Fenceless Industrial and Collaborative Robots 48 2.2.3 Robot Grippers 55 2.3 Planning and Evaluation Methods 56 2.3.1 Planning of General and Manual Workstations 56 2.3.2 Cell Planning for Fully Automated and Hybrid Robot Systems 59 2.3.3 Robot Safety Planning 61 2.3.4 Economic Evaluation Methods 70 2.4 Synthesis - State of the Art and Research 71 3. Solution Approach 77 3.1 Need for Research and General Solution Approach 77 3.2 Use Case Delineation and Planning Focus 80 3.3 Economic Module – Solution Approach 86 3.4 Gripper Feasibility Module – Solution Approach 89 3.5 Rough Layout Discretization Model – Solution Approach 94 3.6 Cycle Time Estimation Module – Solution Approach 97 3.7 Collaborative Speed Estimation Module – Solution Approach 103 3.7.1 General Approach 103 3.7.2 Case 1: Quasi-static Contact with Hand 107 3.7.3 Case 2: Transient Contact with Hand 109 3.7.4 Case 3: Transient Contact with Shoulder 111 3.8 Synthesis – Solution Approach 114 4. Module Development 117 4.1 Economic Module – Module Development 117 4.1.1 General Approach 117 4.1.2 Calculation Scheme for Manual Operation 117 4.1.3 Calculation Scheme for Collaborative Robots 118 4.1.4 Calculation Scheme for Industrial Robots 120 4.2 Gripper Feasibility Module – Module Development 121 4.3 Rough Layout Discretization Module – Module Development 122 4.3.1 General Approach 122 4.3.2 Two-Dimensional Layout Pattern 123 4.3.3 Three-Dimensional Layout Pattern 125 4.4 Cycle Time Estimation Module – Module Development 126 4.4.1 General Approach 126 4.4.2 Reachability Study 127 4.4.3 Simulation Results 128 4.5 Collaborative Speed Estimation Module – Module Development 135 4.5.1 General Approach 135 4.5.2 Case 1: Quasi-static Contact with Hand 135 4.5.3 Case 2: Transient Contact with Hand 143 4.5.4 Case 3: Transient Contact with Shoulder 145 4.6 Synthesis – Module Development 149 5. Practical Verification 155 5.1 Use Case Overview 155 5.2 Gripper Feasibility 155 5.3 Layout Discretization 156 5.4 Collaborative Speed Estimation 157 5.5 Cycle Time Estimation 158 5.6 Economic Evaluation 160 5.7 Synthesis – Practical Verification 161 6. Results and Conclusions 165 6.1 Scientific Findings and Results 165 6.2 Critical Appraisal and Outlook 173 / Initially, industrial robots were mainly operated behind safety fences to account for the safety requirements. With production flexibilization, these sharp separation areas have been increasingly softened by utilizing external safety devices, such as distance sensors, to operate industrial robots fenceless. Based on this idea of coexistence or cooperation, safety technology has been integrated into the robot to enable true collaboration. These collaborative robots, or cobots, open up new application fields and fill the existing automation gap. But which automation variant is most suitable from an economic perspective? Present research dealt primarily isolated with one technology without comparing these systems regarding technological and economic specifics. Therefore, this doctoral thesis pursues a methodology to economically compare collaborative and industrial robots in fenceless machine tending systems. A particular focus lies on distilling the technical factors that mainly influence the profitability to receive a system understanding of the economic structure of both robot technology variants. For examination, the contents of such a planning scheme are described, categorized, systematized, and modularized. A suitable optimization model is presented on the economic side, while the feasibility regarding gripping, layout planning, robot velocities, and cycle time determination is assessed on the technical side. With deductive, simulative, empirical, and statistical methods, the system behavior of the single planning entities is analyzed to predict the overall profitability a priori with a minimum of investment,- production,- and cycle time information. It is demonstrated that the necessary planning data, in terms of layout composition, robot velocities, and cycle times, can be frontloaded to the project’s beginning with a reverse engineering approach. The net present value serves as the target figure, whose dependency on the human-robot interaction grade can be illustrated in an advantageousness diagram for the individual technical alternatives. Consequently, sound economic decisions can be made on a quantitative basis.:1. Introduction 25 1.1 Research Domain 25 1.2 Research Niche 26 1.3 Research Structure 28 2. State of the Art and Research 31 2.1 Turning Machines and Machine Tending 31 2.1.1 Tooling Machine Market Trends and Machine Tending Systems 31 2.1.2 Workpiece System 34 2.1.3 Machine System 36 2.1.4 Logistics System 39 2.1.5 Handling System 41 2.2 Robotics 43 2.2.1 Robot Installation Development and Application Fields 43 2.2.2 Fenceless Industrial and Collaborative Robots 48 2.2.3 Robot Grippers 55 2.3 Planning and Evaluation Methods 56 2.3.1 Planning of General and Manual Workstations 56 2.3.2 Cell Planning for Fully Automated and Hybrid Robot Systems 59 2.3.3 Robot Safety Planning 61 2.3.4 Economic Evaluation Methods 70 2.4 Synthesis - State of the Art and Research 71 3. Solution Approach 77 3.1 Need for Research and General Solution Approach 77 3.2 Use Case Delineation and Planning Focus 80 3.3 Economic Module – Solution Approach 86 3.4 Gripper Feasibility Module – Solution Approach 89 3.5 Rough Layout Discretization Model – Solution Approach 94 3.6 Cycle Time Estimation Module – Solution Approach 97 3.7 Collaborative Speed Estimation Module – Solution Approach 103 3.7.1 General Approach 103 3.7.2 Case 1: Quasi-static Contact with Hand 107 3.7.3 Case 2: Transient Contact with Hand 109 3.7.4 Case 3: Transient Contact with Shoulder 111 3.8 Synthesis – Solution Approach 114 4. Module Development 117 4.1 Economic Module – Module Development 117 4.1.1 General Approach 117 4.1.2 Calculation Scheme for Manual Operation 117 4.1.3 Calculation Scheme for Collaborative Robots 118 4.1.4 Calculation Scheme for Industrial Robots 120 4.2 Gripper Feasibility Module – Module Development 121 4.3 Rough Layout Discretization Module – Module Development 122 4.3.1 General Approach 122 4.3.2 Two-Dimensional Layout Pattern 123 4.3.3 Three-Dimensional Layout Pattern 125 4.4 Cycle Time Estimation Module – Module Development 126 4.4.1 General Approach 126 4.4.2 Reachability Study 127 4.4.3 Simulation Results 128 4.5 Collaborative Speed Estimation Module – Module Development 135 4.5.1 General Approach 135 4.5.2 Case 1: Quasi-static Contact with Hand 135 4.5.3 Case 2: Transient Contact with Hand 143 4.5.4 Case 3: Transient Contact with Shoulder 145 4.6 Synthesis – Module Development 149 5. Practical Verification 155 5.1 Use Case Overview 155 5.2 Gripper Feasibility 155 5.3 Layout Discretization 156 5.4 Collaborative Speed Estimation 157 5.5 Cycle Time Estimation 158 5.6 Economic Evaluation 160 5.7 Synthesis – Practical Verification 161 6. Results and Conclusions 165 6.1 Scientific Findings and Results 165 6.2 Critical Appraisal and Outlook 173

Cable-actuated manipulators (or 'cable robots') constitute a relatively new classification of robots which use motors, located at fixed remote locations, to manipulate an end-effector by extending or retracting cables. These manipulators possess a number of unique properties which make them proficient with tasks involving high payloads, large workspaces, and dangerous or contaminated environments. However, a number of challenges exist which have limited the mainstream emergence of cable robots. This thesis addresses two of the most important of these issues-- workspace analysis and disturbance compensation. Workspace issues are particularly important, as many large-scale applications require the end-effector to operate in regions of a particular shape, and to exert certain minimum forces throughout those regions. The 'Force-Feasible Workspace' represents the set of end-effector positions, for a given robot design, for which the robot can exert a set of required forces on its environment. This can be considered as the robot's 'usable' workspace, and an analysis of this workspace shape for point-mass cable robots is therefore presented to facilitate optimal cable robot design. Numerical simulation results are also presented to validate the analytical results, and to aid visualization of certain complex workspace shapes. Some cable robot applications may require mounting motors to moving bases (i.e. mobile robots) or other surfaces which are subject to disturbances (i.e. helicopters or crane arms). Such disturbances can propagate to the end-effector and cause undesired motion, so the rejection of motor mount disturbances is also of interest. This thesis presents a strategy for measuring these disturbances and compensating for them. General approaches and implementation issues are explored qualitatively with a simple one-degree-of-freedom prototype (including a strategy for mitigating accelerometer drift), and quantitative simulation results are presented as a proof of concept.