Forward Kinematic Model Research Articles

The influence of elbow joint kinematics on wrist speed in cricket fast bowling

This modelling study sought to describe the relationships between elbow joint kinematics and wrist joint linear velocity in cricket fast bowlers, and to assess the sensitivity of wrist velocity to systematic manipulations of empirical joint kinematic profiles. A 12-camera Vicon motion analysis system operating at 250 Hz recorded the bowling actions of 12 high performance fast bowlers. Empirical elbow joint kinematic data were entered into a cricket bowling specific “Forward Kinematic Model” and then subsequently underwent fixed angle, angular offset and angle amplification manipulations. A combination of 20° flexion and 20° abduction at the elbow was shown to maximise wrist velocity within the experimental limits. An increased elbow flexion offset manipulation elicited an increase in wrist velocity. Amplification of elbow joint flexion–extension angular displacement indicated that, contrary to previous research, elbow extension range of motion and angular velocity at the time of ball release were negatively related to wrist velocity. Some relationships between manipulated joint angular waveforms and wrist velocity were non-linear, supporting the use of a model that accounts for the non-linear relationships between execution and outcome variables in assessing the relationships between elbow joint kinematics and wrist joint velocity in cricket fast bowlers.

Error Modeling and Compensation of Circular Motion on a New Circumferential Drilling System

A new flexible circumferential drilling system is proposed to drill on the fuselage docking area. To analyze the influence of the circular motion error to the drilling accuracy, the nominal forward kinematic model is derived using Denavit-Hartenberg (D-H) method and this model is further developed to model the kinematic errors caused by circular positioning error and synchronization error using homogeneous transformation matrices (HTM). A laser tracker is utilized to measure the circular motion error of the two measurement points at both sides. A circular motion compensation experiment is implemented according to the calculated positioning error and synchronization error. Experimental results show that the positioning error and synchronization error were reduced by 65.0% and 58.8%, respectively, due to the adopted compensation, and therefore the circular motion accuracy is substantially improved. Finally, position errors of the two measurement points are analyzed to have little influence on the measurement result and the validity of the proposed compensation method is proved.

Motion capability analysis of a quadruped robot as a parallel manipulator

This paper presents the forward and inverse displacement analysis of a quadruped robot MANA as a parallel manipulator in quadruple stance phase, which is used to obtain the workspace and control the motion of the body. The robot MANA designed on the basis of the structure of quadruped mammal is able to not only walk and turn in the uneven terrain, but also accomplish various manipulating tasks as a parallel manipulator in quadruple stance phase. The latter will be the focus of this paper, however. For this purpose, the leg kinematics is primarily analyzed, which lays the foundation on the gait planning in terms of locomotion and body kinematics analysis as a parallel manipulator. When all four feet of the robot contact on the ground, by assuming there is no slipping at the feet, each contacting point is treated as a passive spherical joint and the kinematic model of parallel manipulator is established. The method for choosing six non-redundant actuated joints for the parallel manipulator from all twelve optional joints is elaborated. The inverse and forward displacement analysis of the parallel manipulator is carried out using the method of coordinate transformation. Finally, based on the inverse and forward kinematic model, two issues on obtaining the reachable workspace of parallel manipulator and planning the motion of the body are implemented and verified by ADAMS simulation.

Research on the Kinematics of Line Heating Robot Based on SVM

The paper mainly analyzed the robot kinematics of the line heating plate. In order to realize the moving of complex trajectory for the robot, a forward kinematics modeling and the simulation of inverse kinematics are carried out. Firstly, with the D-H modeling method, the line heating plate robot forward kinematics equations and the spatial geometric model of the manipulator are set up, then multi-input multi-output systems based on support vector machines algorithm is used to establish the inverse kinematics model for the robot . At last, the simulations of tracing complex trajectory with the inverse kinematics model are carried out, and the results show that the model derived by SVM can trace the trajectory very well.

DESIGN & KINEMATIC ANALYSIS OF AN ARTICULATED ROBOTIC MANIPULATOR

This paper describes the design, fabrication and analysis a five axes articulated robotic manipulator. The current work is undertaken by considering various commercially available robotic kits to design and fabricate a five degree of freedom (D.O.F) arm. Forward kinematic model has been presented in order to determine the end effectors position and orientation. Although this work is still in primary level, this analysis is useful for path tracking of an industrial manipulator with pick-and-place application. Based on this analysis, a researcher can develop path tracking behaviour of an end effector in complicated work space.

Forward Kinematic Modeling and Simulation of Ionic Polymer Metal Composites (IPMC) Actuators for Bionic Knee Joint

Ionic Polymer Composite Material (IPMC) is a flexible material and has revealed many advantages to encourage the scientists and researchers to investigate its characteristics for practical applications in various fields. The ongoing research can be divided into two branches. One deals with the improvement of the material properties to make it more useful and reliable while the other involves the exploration of new application areas. In this paper, Firstly, a new application of IPMC is suggested to actuate a rigid link that can mimic a bionic knee joint for a grass hopper manipulator. Secondly, forward kinematic model is proposed for the manipulator by employing geometric coordinate system method. Lastly, wolfram mathematica software is employed for the simulation of the model. The simulation results based on the model are found very encouraging to lure the article team to carry on the research idea for manufacturing and testing for the comparison of both types of results.

Qualitative approach for forward kinematic modeling of a Compact Bionic Handling Assistant trunk

This paper addresses the forward kinematic model of a class of hyper-redundant continuum robot, namely Compact Bionic Handling Assistant (CBHA). Inspired from the elephant trunk, it can reproduce some biological behaviors of trunks, tentacles, or snakes. Such systems, like the CBHA are subjected to a set of nonlinearities (flexibility, elasticity, redundancy,…) and uncertainties (parameters and modeling), making difficult to build an accurate analytical model, which can be used to develop control strategies. Hence, learning method becomes a suitable approach for such scenarios in order to capture un-modeled nonlinear behaviors of this continuum arm. The proposed approach makes use of Multilayer Perceptron (MLP) and Radial Basis Function (RBF) Neural Networks for the approximation of forward kinematic model (FKM) of CBHA trunk. The experiments have been conducted on the CBHA in order to validate the forward kinematic model where the arm trajectories are generated using a physical coupling with a rigid manipulator. A comparison of both qualitative approaches with a quantitative geometric approach, according to the model accuracy is given at the end of the experiment.

The Kinematics Modeling and Simulation of a Mechanical Arm in Nuclear Industry with Postpositional Drive

For the particularity of the environment in nuclear industry, this paper puts forward a modularized mechanical arm with postpositional drive. On the basis of structural characteristics and kinematic constraints, the kinematics of robotic arm is analyzed. The D-H method is used for describing the workspace, based on considering the kinematic constraints, the forward kinematics model is achieved. Using an improved search method, the inverse kinematics solution is obtained. Through the simulation on data processing software, the validity of positive kinematics model and inverse kinematic solutions are verified. Finally, the trajectory planning is completed on the three-dimensional modeling platform.

Center of Gravity Based, Switching and Partial Modeled Gait Planning

This paper aims for a new structure that can achieve walking by kinematic solutions. The main contribution is having kinematic model of a biped and makes it to have step on open loop form. The paper takes the 5-DOF leg, uses Denavit-Hartenberg convention to obtain forward kinematic models, uses Jacobian matrix to obtain inverse kinematic models. Uses a switching mode models, and switching gaits for tip points and center of gravity. The models and gaits switch by changing support and swing foots. Models are divided into four different models and when models switch two models become active. Using two models gives chance to define two paths for biped, for one step and center of gravity can be controlled separately. By these solutions study aims to make biped to follow these paths. The simulation results from Matlab proved that tip points and center of gravity can make the aimed walking, so that by kinematic constraints stable dynamic walking can be achieved.

Leg kinematic analysis and prototype experiments of walking-operating multifunctional hexapod robot

This paper presents kinematic analysis of a 3-degree of freedom parallel mechanism for hexapod walking-operating multifuctional robot. Each leg of the robot consists of three limbs: universal joint – prismatic joint chain (1-UP) and universal joint – prismatic joint – spherical joint chain (2-UPS) and at the end of the leg there is passive spherical joint to adjust to the uneven ground. In this paper, first the forward kinematic model is built and it shows that the model has close-form solution. Then the work space is discussed in which the robot feet trajectories can be projected. It can be shown that the current trajectories of the feet only take very small work space. After that force analysis is performed and the results show that the payload capability of the mechanism is very high. Experiments of the prototype show that the robot can walk easily with more than 150 kg loads while the step size is more than 0.5 m.

Forward Kinematics of Parallel Robot Based on Neuro-Fuzzy System

As the structure of parallel robot is special in general mechanical and electrical systems, its forward kinematics needs to be solved by nonlinear equations. In this paper, for the issue that numerical iterative method requires complex mathematical derivation and programming, and is sensitive to the initial value, a Neuro-fuzzy system is proposed for solving forward kinematics model of parallel robot. Meanwhile, inverse kinematics is used for training database, knowledge representation ability of fuzzy theory and self-learning ability of neural network are combined to overcome the shortcomings that neural network cannot express human language and fuzzy system do not have self-learning ability. In addition, training and generation efficiency of the model can also be improved by reducing the input dimension reasonably. Simulation results have been showed that, in the premise of efficiency, accuracy of forward kinematics model using Neuro-fuzzy system is better than Newton-Raphson iterative method, and has better versatility.

Forward kinematics analysis and experimental validation of a four-cable-driven under-constrained parallel mechanism

Taking the sinking winch mechanism as prototype, this paper studies the forward kinematics problem of a four-cable-driven under-constrained parallel mechanism. The tension states (slackness and tautness) and properties of the cables are incorporated into the forward kinematics model. We propose a new algorithm (named traversal algorithm) to solve the tensions in cables and the pose of platform, under the condition that only the lengths of four cables are known. The simulation and experimental results on forward kinematics demonstrate the effectiveness and correctness of the model and the traversal algorithm. The results of this paper can be used to evaluate the effect of the unequal cables’ lengths to the tension distribution of cables and pose of the platform for sinking winch mechanism.

A Microfabricated Planar Digital Microrobot for Precise Positioning Based on Bistable Modules

Size reduction is a constant objective in new technologies for which very accurate devices are needed when manipulating submillimetric objects. A new kind of microfabricated microrobot based on the use of bistable modules is designed to perform open-loop controlled micropositioning tasks. The DiMiBot (a specific digital microrobot) opens a new paradigm in the design of microrobots by using mechanical stability instead of complex control strategies. We propose a new architecture of digital microrobot for which forward and inverse kinematics models are easy to use. These kinematic models are validated with finite-element-analysis simulations before the fabrication of a real DiMiBot prototype. Tests and characterization of the prototype are made and compared with the desired behavior. Thanks to its submicrometric resolution and to its small dimensions (~ 400-μm thickness), it is able to manipulate microobjects in confined environments, where no other robot can be used.

A kinematic model for the formation of the Siletz‐Crescent forearc terrane by capture of coherent fragments of the Farallon and Resurrection plates

AbstractThe volcanic basement of the Oregon and Washington Coast ranges has been proposed to represent a pair of tracks of the Yellowstone hotspot formed at a mid‐ocean ridge during the early Cenozoic. This interpretation has been questioned on many grounds, especially that the range of ages does not match the offshore spreading rates and that the presence of continental coarse clastic sediments is difficult to reconcile with fast convergence rates between the oceanic plates and North America. Updates to basement geochronology and plate motion history reveal that these objections are much less serious than when they were first raised. Forward plate kinematic modeling reveals that predicted basement ages can be consistent with the observed range of about 55–49 Ma, and that the entire basement terrane can form within about 300 km of continental sources for clastic sediments. This kinematic model indicates that there is no firm reason to reject the near‐ridge hotspot hypothesis on the basis of plate motions. A novel element of the model is the Resurrection plate, previously proposed to exist between the Farallon and Kula plates. By including the defunct Resurrection plate in our reconstruction, we are able to model the Farallon hotspot track as docking against the Oregon subduction margin starting about 53 Ma, followed by docking of the Resurrection track to the north starting about 48 Ma. Accretion of the Farallon plate fragment and partial subduction of the Resurrection fragment complicates the three‐dimensional structure of the modern Cascadia forearc. We interpret the so‐called “E” layer beneath Vancouver Island to be part of the Resurrection fragment. Our new kinematic model of mobile terranes within the Paleogene North American plate boundary allows reinterpretation of the three‐dimensional structure of the Cascadia forearc and its relationship to ongoing seismotectonic processes.

Forward Kinematics Modeling of 5 DOF Stationary Articulated Robots

Forward Kinematics Modeling of 5 DOF Stationary Articulated Robots

Jacobian Matrix of a Novel Continuum Robot for Search and Rescue

In this paper, a novel continuum robot for search and rescue is presented. A forward kinematic model is derived by product of exponentials formula, compare with conventional D-H method, this method is concise and simplicity. Finally, based on the differential kinematics using the chain rule, the overall Jacobian of the robot is established. This approach can be generally applied to various continuum robots, regardless of the specific actuation system used.

Kinematics Performance Simulation and Optimization of Large Face-Shovel Hydraulic Excavator Working Device Based on ADAMS

In order to study the influence of key hinge point’s positions to the kinematical performance of the face-shovel hydraulic excavator working device, a forward kinematics model of the working device is presented firstly. And then the simulation model is established in ADAMS. The working processes are simulated and the bucket digging envelope diagram is drawn. Then different simulation models in ADAMS are established by using Monte Carlo method to sample data which are the range of key hinge point’s position. According to a certain order and requirement of objective response, the model with better motive performance can be chosen. The results show that the chosen model has better kinematical performance than that of the initial model where all of important objective responses can be improved differently.

Error Modeling of a Parallel Wedge Precision Positioning Stage

The parallel wedge precision positioning stage (PW-PPS) presents a novel configuration of a parallel mechanism for precision positioning applications. Based on its specific parallel configuration, the corresponding inverse and forward kinematic models were developed and used to formulate the volumetric error model of the mechanism. The error model that considers the influence of manufacturing errors is built in two steps. In the first, the structural parameter-induced errors associated with the PW-PPS's structural parameters and input variables were considered, while in the second, the joint clearance-induced errors produced by joint clearances were taken into account. The structural parameter-induced errors were modeled based on complete differential-coefficient theory, while the joint clearance-induced errors due to joint clearances were modeled based on the virtual work and deterministic method. In the latter case, the kinetostatic model and joint error contact modes were analyzed to build a joint clearance-induced error model. The relationship between the different error sources and the output pose error of the mechanism's moving platform was obtained. Finally, considering practical values for the mechanism's parameters and errors, the error distribution in the PW-PPS's workspace was evaluated to determine the distributive rules of the various error components.

AUTONOMOUS ONLINE LEARNING OF REACHING BEHAVIOR IN A HUMANOID ROBOT

In this paper we describe an autonomous strategy which enables a humanoid robot to learn how to reach for a visually identified object in the 3D space. The robot is a 22-DOF upper-body humanoid with moving eyes, neck, arm and hand. The robot is bootstrapped with limited a-priori knowledge, sufficient to start the interaction with the environment; this interaction allows the robot to learn different sensorimotor mappings, required for reaching. The arm-head forward kinematic model and a visuo-motor inverse model are learned from sensory experience. Learning is performed purely online (without any separation between training and execution) through a goal-directed exploration of the environment. During the learning the robot is also able to build an internal representation of its reachable space.

A bio-inspired kinematic controller for obstacle avoidance during reaching tasks with real robots

This paper describes a redundant robot arm that is capable of learning to reach for targets in space in a self-organized fashion while avoiding obstacles. Self-generated movement commands that activate correlated visual, spatial and motor information are used to learn forward and inverse kinematic control models while moving in obstacle-free space using the Direction-to-Rotation Transform (DIRECT). Unlike prior DIRECT models, the learning process in this work was realized using an online Fuzzy ARTMAP learning algorithm. The DIRECT-based kinematic controller is fault tolerant and can handle a wide range of perturbations such as joint locking and the use of tools despite not having experienced them during learning. The DIRECT model was extended based on a novel reactive obstacle avoidance direction (DIRECT-ROAD) model to enable redundant robots to avoid obstacles in environments with simple obstacle configurations. However, certain configurations of obstacles in the environment prevented the robot from reaching the target with purely reactive obstacle avoidance. To address this complexity, a self-organized process of mental rehearsals of movements was modeled, inspired by human and animal experiments on reaching, to generate plans for movement execution using DIRECT-ROAD in complex environments. These mental rehearsals or plans are self-generated by using the Fuzzy ARTMAP algorithm to retrieve multiple solutions for reaching each target while accounting for all the obstacles in its environment. The key aspects of the proposed novel controller were illustrated first using simple examples. Experiments were then performed on real robot platforms to demonstrate successful obstacle avoidance during reaching tasks in real-world environments.