Kinematics and Robot Design I, KaRD2018

This volume collects the papers published on the Special Issue “Kinematics and Robot Design I, KaRD2018” (https://www.mdpi.com/journal/robotics/special_issues/KARD), which is the first issue of the KaRD Special Issue series, hosted by the open access journal “MDPI Robotics”. The KaRD series aims at creating an open environment where researchers can present their works and discuss all the topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”. KaRD2018 received 22 papers and, after the peer-review process, accepted only 14 papers. The accepted papers cover some theoretical and many design/applicative aspects

Architectural study of the design and operation of advanced force feedback manual controllers

A teleoperator system consists of a manual controller, control hardware/software, and a remote manipulator. It was employed in either hazardous or unstructured, and/or remote environments. In teleoperation, the main-in-the-loop is the central concept that brings human intelligence to the teleoperator system. When teleoperation involves contact with an uncertain environment, providing the feeling of telepresence to the human operator is one of desired characteristics of the teleoperator system. Unfortunately, most available manual controllers in bilateral or force-reflecting teleoperator systems can be characterized by their bulky size, high costs, or lack of smoothness and transparency, and elementary architectures. To investigate other alternatives, a force-reflecting, 3 degree of freedom (dof) spherical manual controller is designed, analyzed, and implemented as a test bed demonstration in this research effort. To achieve an improved level of design to meet criteria such as compactness, portability, and a somewhat enhanced force-reflecting capability, the demonstration manual controller employs high gear-ratio reducers. To reduce the effects of the inertia and friction on the system, various force control strategies are applied and their performance investigated. The spherical manual controller uses a parallel geometry to minimize inertial and gravitational effects on its primary task of transparent information transfer. As an alternative to the spherical 3-dof manual controller, a new conceptual (or parallel) spherical 3-dof module is introduced with a full kinematic analysis. Also, the resulting kinematic properties are compared to those of other typical spherical 3-dof systems. The conceptual design of a parallel 6-dof manual controller and its kinematic analysis is presented. This 6-dof manual controller is similar to the Stewart Platform with the actuators located on the base to minimize the dynamic effects. Finally, a combination of the new 3-dof and 6-dof concepts is presented as a feasible test-bed for enhanced performance in a 9-dof system

Controlo de uma plataforma servo-hidráulica com cinemática paralela para estampagem incremental

Mestrado em Engenharia MecânicaSPIF-A is an innovative project about Gough-Stewart platform using parallel kinematics for incremental forming that is supported by different fields of engineering. It is a long term work composed by a professional team that includes professors, students and researchers fancying to improve and contribute for scientific knowledge. Incremental forming is emerging due to its useful advantages, highlighting the high-speed machining. The objective is the control of a Gough-Stewart platform, planning and execution of G-code trajectories. Thereunto, a state-of-the-art regarding incremental forming, parallel platforms, parallel kinematics and control theory is carried out. Position controllers and trajectory planning are developed and implemented for a 6 degree-of-freedom manipulator. Accuracy and reliability tests are done to consummate an hardware improvement. Some types of controllers, based in fuzzy logic and one linear PID, were studied and executed on this platform in order to improve its control system.SPIF-A é um projecto inovador sobre uma plataforma de Gough- Stweart com cinemática paralela para estampagem incremental que abrange inúmeras áreas da engenharia. É um trabalho de longa data composto por uma equipa de profissionais entre professores, estudantes e investigadores que visa estimular o conhecimento científico. A estampagem incremental está muito em voga uma vez que as suas vantagens são tremendas. Dentro desta, destaca-se a estampagem incremental de alta velocidade. O objetivo é então o controlo de uma plataforma Gough-Stewart, planeamento e execução de trajetórias ISO. Para isso, é feita uma revisão do estado da arte sobre estampagem incremental, plataformas paralelas, cinemática paralela e teoria de controladores. São desenvolvidos e implementados controladores de posição e definidas trajetórias para um manipulador de 6 graus de liberdade. São levados a cabo testes de precisão e fiabilidade do hardware do manipulador tendo em vista a sua melhoria futura. Uma série de controladores, baseados em lógica difusa e um controlador PID linear, foram estudados e testados durante a implementação do novo hardware na plataforma tendo em conta a melhoria de todo o seu sistema de controlo

Prospects for commercialization of SELV-based in-space operations

A workshop was hosted by the Langley Research Center as a part of an activity to assess the commercialization potential of Small Expendible Launch Vehicle-based in-space operations. Representatives of the space launch insurance industry, industrial consultants, producers of spacecraft, launch vehicle manufacturers, and government researchers constituted the participants. The workshop was broken into four sessions: Customers Small Expendible Launch Systems, Representative Missions, and Synthesis-Government role. This publication contains the presentation material, written synopses of the sessions, and conclusions developed at the workshop

Symbolic Automation and Numerical Synthesis for Robot Kinematics

This research analyzes three topics in robot arm kinematics. First, the direct kinematics which determines the Cartesian position and orientation of the end effector for the specified values of joint parameters is analyzed. Second, the differential motions concerning the differential relationships between the command variables in position and orientation of the end effector and the joint-controlled variables are studied. Finally, the inverse kinematics which determines the joint variables for a specified Cartesian position and orientation of the end effector is considered. This dissertation presents a methodology for incorporating the artificial intelligence types of knowledge into automating solutions for the direct kinematics problem and the manipulator Jacobian matrix. Furthermore, the dissertation utilizes the backward recursive techniques, the trigonometric identity rules, and a set of heuristic rules for implementing this methodology. To expedite computation efforts, a new algorithm is developed to obtain a differential relationship of a robotic manipulator via the vector kinematics method. Moreover, the speed control model for general robotic manipulators, together with the inverse Jacobian regarding cases of under-determined and over-determined of joint-controlled variables, are also discussed. Three mathematical approaches are proposed for solving the inverse kinematics problem: the inverse homogeneous transformation matrices approach, the geometric approach, and the arm-wrist partitioned synthesis approach. The first two approaches yield the symbolic closed-form solutions; the last approach, based on the iterative technique, provides a maximum of 16 distinct solutions of joint motion variables for any given position and orientation of the end effector in the workspace

Modeling and Control of the UGV Argo J5 with a Custom-Built Landing Platform

This thesis aims to develop a detailed dynamic model and implement several navigation controllers for path tracking and dynamic self-leveling of the Argo J5 Unmanned Ground Vehicle (UGV) with a custom-built landing platform. The overall model is derived by combining the Argo J5 driveline system with the wheelsterrain interaction (using terramechanics theory and mobile robot kinetics), while the landing platform model follows the Euler-Lagrange formulation. Different controllers are, then, derived, implemented to demonstrate: i.) self-leveling accuracy of the landing platform, ii.) trajectory tracking capabilities of the Argo J5 when moving in uneven terrains. The novelty of the Argo J5 model is the addition of a vertical load on each wheel through derivation of the shear stress depending on the point’s position in 3D space on each wheel. Static leveling of the landing platform within one degree of the horizon is evaluated by implementing Proportional Derivative (PD), Proportional Integral Derivative (PID), Linear Quadratic Regulator (LQR), feedback linearization, and Passivity Based Adaptive Controller (PBAC) techniques. A PD controller is used to evaluate the performance of the Argo J5 on different terrains. Further, for the Argo J5 - landing platform ensemble, PBAC and Neural Network Based Adaptive Controller (NNBAC) are derived and implemented to demonstrate dynamic self-leveling. The emphasis is on different controller implementation for complex real systems such as Argo J5 - Landing platform. Results, obtained via extensive simulation studies in a Matlab/Simulink environment that consider real system parameters and hardware limitations, contribute to understanding navigation performance in a variety of terrains with unknown properties and illustrate the Argo J5 velocity, wheel rolling resistance, wheel turning resistance and shear stress on different terrains

Large space structures and systems in the space station era: A bibliography with indexes

Bibliographies and abstracts are listed for 1219 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1990 and December 31, 1990. The purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system, interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems

Orbital service module systems analysis study documentation. Volume 2: Technical report

Near term, cost effective concepts were defined to augment the power and duration capability offered to shuttle payload users. Feasible concept options that could evolve to provide free-flying power and other services to users in the 1984 time frame were also examined

1999 Flight Mechanics Symposium

This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on May 18-20, 1999. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers