Search results for "kinematics"

Modelling, Identification and Control of a 5-DOF Shotcrete Robot : Development of a Framework for Automatic Application of Shotcrete for AMV 4200H

2019

Master's thesis Mechatronics MAS500 - University of Agder 2019 Today, process automation is the primary area of development in the shotcrete industry. Automaticshotcrete operations can yield an increase in operational efficiency and personnel safety as well asreductions in cost and environmental impact. This thesis develops a framework for automaticapplication of shotcrete using the AMV 4200H and provides an automatic spraying mode usinginteroceptive sensing. The shotcrete vehicle is equipped with a five degrees-of-freedom manipulatorand is currently operated manually. Our contributions include solving the forward kinematicsthrough the Denavit-Hartenberg convention, and the inverse kinemati…

Finite-Element Modeling of Floodplain Flow

2000

A new methodology for a robust solution of the diffusive shallow water equations is proposed. The methodology splits the unknowns of the momentum and continuity equations into one kinematic and one parabolic component. The kinematic component is solved using the slope of the water level surface computed in the previous time-step and a zero-order approximation of the water head inside the mass-balance area around each node of the mesh. The parabolic component is found by applying a standard finite-element Galerkin procedure, where the source terms can be computed from the solution of the previous kinematic problem. A simple 1D case, with a known analytical solution, is used to test the accur…

Negative and positive feedback from a supernova remnant with SHREC

2022

Supernova remnants (SNRs) contribute to regulate the star formation efficiency and evolution of galaxies. As they expand into the interstellar medium (ISM), they transfer vast amounts of energy and momentum that displace, compress and heat the surrounding material. Despite the extensive work in galaxy evolution models, it remains to be observationally validated to what extent the molecular ISM is affected by the interaction with SNRs. We use the first results of the ESO-ARO Public Spectroscopic Survey SHREC, to investigate the shock interaction between the SNR IC443 and the nearby molecular clump G. We use high sensitivity SiO(2-1) and H$^{13}$CO$^+$(1-0) maps obtained by SHREC together wit…

Study upon the kinematic simulation of the incremental forming carried-on using a serial industrial robot

2021

Abstract Incremental forming with contact between tool-sheet metal workpiece in a single point is an unconventional process which allow the user to manufacture parts by combining the vertical movement of the tool along Z-axis and the horizontal movements of sheet metal workpiece, which are performed in XY plane. As technological equipment able to control coordinated movements on three axes, CNC machining centers and industrial serial robots with six degrees of freedom are the most suitable. The paper introduces a study regarding the use of robots as technological equipment for the process, by means of simulation. Supplementary degrees of freedom and singularities avoidance are also consider…

Method for estimating combined controller, joint and link stiffnesses of an industrial robot

2014

In this paper a new combined local/global approach for estimating the combined stiffnesses of joints in anthropomorphic robots is presented. The stiffness of each joint is a combination of several effects: i) stiffness of the links, ii) stiffness of joint bearings and gears and iii) stiffness of the position control loops given by the individual axis controller gains in the controller software. Experimental results are presented for an ABB IRB6600 industrial robot using measurements from a FARO Xi laser tracker and an ATI Omega160 force/torque sensor. The results show that there is a significant variation in stiffness among the individual joints of the robot and that the stiffnesses of the …

Learning high-level manipulative tasks through imitation

2006

This paper presents ConSCIS, Conceptual Space based Cognitive Imitation System, which tightly links low-level data processing with knowledge representation in the context of robot imitation. Our focus is on the program-level imitation: we are interested in the final effects of actions on objects, and not on the particular kinematic or dynamic properties of the motion. The same architecture is used both to analyze and represent the task to be imitated, and to perform the imitation by generalizing in novel and different circumstances. The implemented experimental scenario is a two dimensional world populated with various objects in which observation/imitation takes place. To validate our appr…

Dynamic Analysis of a 7 DOF Robot Using Fuzzy Logic for Inverse Kinematics Problem

2019

Abstract In this paper, a dynamic analysis for a redundant, serial robot, with seven degrees of freedom is presented. The dynamic model of the robot is based on importing a tri-dimensional CAD model of the robot into MATLAB®, Simulink®-Simscape™-SimMechanics™. One can import complete CAD assemblies, including all masses, inertias, joints, constraints, and tri-dimensional geometries, into the model. The first step for executing a dynamic analysis is to resolve the Inverse Kinematics (IK) problem for the redundant robot. Because this type of robot has seven degrees of freedom the IK resolution implies an infinite number of solutions. So, to be able to resolve the IK for this kind of robot a F…

Measurement and storage of a network of jacobians as a method for the visual positioning of a robot arm

1996

The goal of this paper is to describe a method to position a robot arm at any visible point of a given workspace without an explicit on line use of the analytical form of the transformations between real space and camera coordinates (camera calibration) or between cartesian and joint coordinates (direct or inverse kinematics of the robot arm). The formulation uses a discrete network of points distributed all over the workspace in which a procedure is given to measure certain Jacobian matrices which represent a good local linear approximation to the unknown compound transformation between camera and joint coordinates. This approach is inspired by the biological observation of the vestibulo-o…

The future of sensorimotor communication research

2019

Three-Dimensional Kinematics during the Take-Off Phase in Competitive Long Jumping

2013

The purpose of the present study was to identify the relationships among selected kinematic variables that affect the take-off phase and performance in elite jumpers. The jump distance was found to be related to: I) the athlete's approach speed before the instant of touch down; and ii) the exchange in spatial velocity components at take-off, which results in a gain in maximum vertical velocity of the centre of mass (CM), favoured by the use of an optimum touch-down angle of the take-off leg, an active landing of the foot at touch-down, and a motion of the take-off leg during the compression phase that helps to manage the loss of horizontal velocity. Nonetheless, the results show that an ad…