A kinematically complete quasifree (p, pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus 17B, which had long been considered to have a neutron halo. ...By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s1/2 and 0d5/2 orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s1/2. Our finding of such a small 1s1/2 component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in 17B. The present work gives the smallest s - or p -orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.
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In this article, we propose a new method for multirobot systems to have reactive responses to various collision scenarios in real time. This method contains a novel Formula Omitted-norm ...approximation-based reactive approach, which allows multiple robots to avoid mutual collisions or to adapt to the collisions with intelligently regulated force. Compared with existing approaches, the implementation of the proposed method is simpler and more convenient since our reactive approach works as several linear quadratic programming constraints, allowing for flexible utilization by inverse kinematics solvers. In addition, it requires low computational complexity, achieves high accuracy, and does not need training. In the experiments, we employ a multirobot system to conduct comprehensive comparisons between the proposed method and state-of-the-art approaches, effectively showcasing the efficacy of our work.
The paper presents a fast online predictive method to solve the task-priority differential inverse kinematics of redundant manipulators under kinematic constraints. It implements a task-scaling ...technique to preserve the desired geometrical task, when the trajectory is infeasible for the robot capabilities. Simulation results demonstrate the effectiveness of the methodology.
A solving method for the inverse-kinematics （IK） problem of a kind of 6 degree of freedom （DOF） manipulator with the axes of the 3 adjacent rotational joints in the arm part，shoulder，elbow and wrist ...parallel is presented. The merit of this method is that，by utilizing the geometrical relation between the end-effector，hand and wrist of the manipulator determined by its structure，the position of the wrist corresponding to a desired end-effector orientation and position can be solved at the first step in the whole calculation process. And then，the solution of a 6-variable equations，which describes the relationship between the 6 joint positions of the manipulator and its end-effector orientation and position is reduced into two 3-variable equations，one of which describes the relationship between the wrist position and the positions of 3 joints distributed in the shoulder and elbow，and the other describes the relationship between the end-effector orientation and the positions of the rest 3 joint distributed in the
The structure of a neutron-rich 25F nucleus is investigated by a quasifree (p,2p) knockout reaction at 270 A MeV in inverse kinematics. The sum of spectroscopic factors of π0d5/2 orbital is found to ...be 1.0 ± 0.3 . However, the spectroscopic factor with residual 24O nucleus being in the ground state is found to be only 0.36 ± 0.13 , while those in the excited state is 0.65 ± 0.25 . The result shows that the 24O core of 25F nucleus significantly differs from a free 24O nucleus, and the core consists of ∼ 35 % 24Og.s. and ∼ 65 % excited 24O. The result may infer that the addition of the 0d5/2 proton considerably changes neutron structure in 25F from that in 24O, which could be a possible mechanism responsible for the oxygen dripline anomaly.
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In view of the complexity of the traditional inverse kinematics solution, it is solved by the mapping of the BP neural network, but the precision is low and the network performance is not good. By ...using FGA to optimize BP neural network, the shortcomings of the neural network itself can be overcome. Taking the pose matrix and joint angle of the manipulator as the input and output variables of the prediction network, the inverse solution prediction BP network of the manipulator is constructed, and then samples are selected for training. Finally, the network test and simulation results show that the optimized BP neural network has higher prediction precision and improved network performance.
Inverse kinematics is a crucial topic in robotics, enabling robots to calculate the joint angles required to achieve the desired end effector position and orientation. Solving the inverse kinematics ...problem quickly with high accuracy is vital for robot manipulators. If sufficient speed is provided, the real-time motion planning task of robot manipulators can be achieved. Real-time motion planning of complex robot manipulators is not possible with classical mathematical methods. Overcoming this problem will provide many benefits in the design and control of robot manipulators. In contemporary research, metaheuristic approaches have become widely employed for addressing the inverse kinematics problem. This investigation utilizes the efficient and simple Ali Baba and the Forty Thieves (AFT) algorithm to resolve the inverse kinematics problem. To increase convergence speed of AFT, a parameter has been used in early iterations of the algorithm to prevent thieves from randomly searching within the search area to find Ali Baba when they realized they had been deceived. Additionally, an approach has been proposed regarding the accuracy of the information brought by the Marjaneh. Finally, the inverse kinematics solution of the 7-DOF robot manipulator was carried out comparatively.
Abstract
The painting on tall structures, statues, monuments and buildings is dangerous task for humans. Robotics finds its applications in operations, which are repetitive, hazardous, and dangerous. ...The aim of the present work is to design a manipulator for spray painting on surfaces of tall monuments, statues and structures. The robot can be installed on a crane platform for lifting and operated from the ground. A lightweight and compact design is desired that can be easily accommodated within the space of the crane. A Revolute-Revolute-Revolute-Prismatic (RRRP) type Robotic arm is developed and analysed for this application. By establishing the rigid body tree model in Robotics System Toolbox, the numerical model of direct and inverse kinematics using Homogenous Matrix Transformation is prepared in MATLAB. Using the spray patch method and offline programming method, the spray model is prepared in Solid woks to obtain trajectory waypoints. A B-spline path is generated through these waypoints. At each waypoint, joint displacement variables are calculated using an inverse kinematic model. An air-less spray gun is selected and attached with a robot. Controlled motion algorithm for spray painting operation on a circular surface were obtained with simulation results. A smooth trajectory for performing spray painting is obtained.
Solving the analytical inverse kinematics (IK) of redundant manipulators in real time is a difficult problem in robotics since its solution for a given target pose is not unique. Moreover, choosing ...the optimal IK solution with respect to application-specific demands helps to improve the robustness and to increase the success rate when driving the manipulator from its current configuration towards a desired pose. This is necessary, especially in high-dynamic tasks like catching objects in mid-flights. To compute a suitable target configuration in the joint space for a given target pose in the trajectory planning context, various factors such as travel time or manipulability must be considered. However, these factors increase the complexity of the overall problem which impedes real-time implementation. In this paper, a real-time framework to compute the analytical inverse kinematics of a redundant robot is presented. To this end, the analytical IK of the redundant manipulator is parameterized by so-called redundancy parameters, which are combined with a target pose to yield a unique IK solution. Most existing works in the literature either try to approximate the direct mapping from the desired pose of the manipulator to the solution of the IK or cluster the entire workspace to find IK solutions. In contrast, the proposed framework directly learns these redundancy parameters by using a neural network (NN) that provides the optimal IK solution with respect to the manipulability and the closeness to the current robot configuration. Monte Carlo simulations show the effectiveness of the proposed approach which is accurate and real-time capable (≈ 32µs) on the KUKA LBR iiwa 14 R820.
•Machine Learning-based Framework for Analytical Inverse Kinematics for Redundant Manipulators•Online Inverse Kinematics for Redundant Manipulators.•Learning redundancy parameters of Analytical Inverse Kinematics using Neural Network.•Direct collocation trajectory optimization.
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