Manned simulations of the SRMS in SIMFAC

SIMFAC is a general purpose real-time simulation facility currently configured with an Orbiter-like Crew Compartment and a Displays and Controls (D and C) Subsystem to support the engineering developments of the Space Shuttle Remote Manipulator (SRMS). The simulation consists of a software model of the anthropomorphic SRMS manipulator arm including the characteristics of its control system and joint drive modules. The following are discussed: (1) simulation and scene generation subsystems; (2) the SRMS task in SIMFAC; (3) operator tactics and options; (4) workload; (5) operator errors and sources; (6) areas for further work; and (7) general observations

Design and Modeling of 9 Degrees of Freedom Redundant Robotic Manipulator

In disaster areas, robot manipulators are used to rescue and clearance of sites. Because of the damaged area, they encounter disturbances like obstacles, and limited workspace to explore the area and to achieve the location of the victims. Increasing the degrees of freedom is required to boost the adaptability of manipulators to avoid disturbances, and to obtain the fast desired position and precise movements of the end-effector. These robot manipulators offer a reliable way to handle the barrier challenges since they can search in places that humans can't reach. In this research paper, the 9-DOF robotic manipulator is designed, and an analytical model is developed to examine the system’s behavior in different scenarios. The kinematic and dynamic representation of the proposed model is analyzed to obtain the translation or rotation, and joint torques to achieve the expected position, velocity, and acceleration respectively. The number of degrees may be raised to avoid disturbances, and to obtain the fast desired position and precise movements of the end-effector. The simulation of developed models is performed to ensure the adaptable movement of the manipulators working in distinct configurations and controlling their motion thoroughly and effectively. In the proposed configuration the joints can easily be moved to achieve the desired position of the end-effector and the results are satisfactory. The simulation results show that the redundant manipulator achieves the victim location with various configurations of the manipulator. Results reveal the effectiveness and efficacy of the proposed system

Optimal dimensional synthesis of a symmetrical five-bar planar upper-extremity neuromotor device

Individuals with hemiplegia suffer from impaired arm movements that appear as a marked change in arm stiffness. A quantitative measure of arm stiffness would characterize rehabilitation therapy effectively, while little mechanism is designed to implement the function. A symmetrical five-bar linkage consisting of two revolute joints and three prismatic joints is presented. Inverse kinematics and forward kinematics are obtained first. Then inverse singularities and direct singularities of the mechanism are gained. Based on the results of kinematics analysis, the global stiffness index is defined. Finally, optimal dimensional synthesis of the mechanism in terms of maximum stiffness is conducted by genetic algorithms. The calculation results shows that when length of both the two linkage a=830 mm, interacting angle of the two guides 2d=4.48 radian, and maximum range of displacement of the two carriers dmax=940 mm, the mechanism achieves highest rigidity and its workspace is singularity-free, which covers the human left and right arm range of motion. The proposed novel mechanism featuring high rigidity and a singularity-free workspace can provides rehabilitation training, but also solves the problem of quantitative measure of arm stiffness

Kinematics and Robot Design II (KaRD2019) and III (KaRD2020)

This volume collects papers published in two Special Issues “Kinematics and Robot Design II, KaRD2019” (https://www.mdpi.com/journal/robotics/special_issues/KRD2019) and “Kinematics and Robot Design III, KaRD2020” (https://www.mdpi.com/journal/robotics/special_issues/KaRD2020), which are the second and third issues of the KaRD Special Issue series hosted by the open access journal robotics.The KaRD series is an open environment where researchers present their works and discuss all topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. It aims at being an established reference for researchers in the field as other serial international conferences/publications are. Even though the KaRD series publishes one Special Issue per year, all the received papers are peer-reviewed as soon as they are submitted and, if accepted, they are immediately published in MDPI Robotics. 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”.KaRD2019 together with KaRD2020 received 22 papers and, after the peer-review process, accepted only 17 papers. The accepted papers cover problems related to theoretical/computational kinematics, to biomedical engineering and to other design/applicative aspects

NASA/NBS (National Aeronautics and Space Administration/National Bureau of Standards) standard reference model for telerobot control system architecture (NASREM)

The document describes the NASA Standard Reference Model (NASREM) Architecture for the Space Station Telerobot Control System. It defines the functional requirements and high level specifications of the control system for the NASA space Station document for the functional specification, and a guideline for the development of the control system architecture, of the 10C Flight Telerobot Servicer. The NASREM telerobot control system architecture defines a set of standard modules and interfaces which facilitates software design, development, validation, and test, and make possible the integration of telerobotics software from a wide variety of sources. Standard interfaces also provide the software hooks necessary to incrementally upgrade future Flight Telerobot Systems as new capabilities develop in computer science, robotics, and autonomous system control

Design and test of a parallel kinematic solar tracker

This article proposes a parallel kinematic solar tracker designed for driving high-concentration photovoltaic modules. This kind of module produces energy only if they are oriented with misalignment errors lower than 0.4°. Generally, a parallel kinematic structure provides high stiffness and precision in positioning, so these features make this mechanism fit for the purpose. This article describes the work carried out to design a suitable parallel machine: an already existing architecture was chosen, and the geometrical parameters of the system were defined in order to obtain a workspace consistent with the requirements for sun tracking. Besides, an analysis of the singularities of the system was carried out. The method used for the singularity analysis revealed the existence of singularities which had not been previously identified for this kind of mechanism. From the analysis of the mechanism developed, very low nominal energy consumption and elevated stiffness were found. A small-scale prototype of the system was constructed for the first time. A control algorithm was also developed, implemented, and tested. Finally, experimental tests were carried out in order to verify the capability of the system of ensuring precise pointing. The tests have been considered passed as the system showed an orientation error lower than 0.4° during sun tracking

Robotic technologies of the Flight Telerobotic Servicer (FTS) including fault tolerance

The original FTS concept for Space Station Freedom (SSF) was to provide telerobotic assistance to enhance crew activity and safety and to reduce crew EVA (Extra Vehicular Activity) activity. The first flight of the FTS manipulator systems would demonstrate several candidate tasks and would verify manipulator performance parameters. These first flight tasks included unlocking a SSF Truss Joint, mating/demating a fluid coupling, contact following of a contour board, demonstrating peg-in-hole assembly, and grasping and moving a mass. Future tasks foreseen for the FTS system included ORU (Orbit Replaceable Unit) change-out, Hubble Space Telescope Servicing, Gamma Ray Observatory refueling, and several in-situ SSF servicing and maintenance tasks. Operation of the FTS was planned to evolve from teleoperation to fully autonomous execution of many tasks. This wide range of mission tasks combined with the desire to evolve toward fully autonomy forced several requirements which may seen extremely demanding to the telerobotics community. The FTS requirements appear to have been created to accommodate the open-ended evolution plan such that operational evolution would not be impeded by function limitations. A recommendation arising from the FTS program to remedy the possible impacts from such ambitious requirements is to analyze candidate robotic tasks. Based on these task analyses, operational impacts against development impacts were weighed prior to requirements definition. Many of the FTS requirements discussed in the following sections greatly influenced the development cost and schedule of the FTS manipulator. The FTS manipulator has been assembled at Martin Marietta and is currently in testing. Successful component tests indicate a manipulator which achieves unprecedented performance specifications

Robot Manipulators

Robot manipulators are developing more in the direction of industrial robots than of human workers. Recently, the applications of robot manipulators are spreading their focus, for example Da Vinci as a medical robot, ASIMO as a humanoid robot and so on. There are many research topics within the field of robot manipulators, e.g. motion planning, cooperation with a human, and fusion with external sensors like vision, haptic and force, etc. Moreover, these include both technical problems in the industry and theoretical problems in the academic fields. This book is a collection of papers presenting the latest research issues from around the world

Geometric Perspective on Kinematics and Singularities of Spatial Mechanisms

This doctoral dissertation deals with the kinematics and singularity analyses of serial and parallel manipulators with multiple working modes. The inverse kinematics of 6R architectures with non-spherical wrists were solved using simple geometric considerations; the problem was reduced to the solution of a trigonometric equation in one variable, the sixth joint angle. The direct kinematic analysis of the parallel manipulator, namely the Exechon, was conducted; it involves using a standard numerical tool to solve the system of equations in platform\u2019s angle variables. Both kinematics analyses took advantage of the standard numerical solver to obtain the solutions. The singularities of the Exechon were studied with the geometrical interpretation. By using the theory of reciprocal screws, the input-output velocity equations were introduced. This led to the investigation of the Jacobian matrices, which is an essential part when working with any manipulator. A method for obtaining the singularity loci and the numerical example was provided. The formulations presented in this dissertation are general and effective enough to be applicable for many other similar architectures