The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper presents the design, development and implementation of a Hybrid Adaptive Fuzzy Controller (HAFC) suitable for real-time industrial applications. The developed HAFC consists of a weighted combination of the Direct Adaptive Fuzzy Controller (DAFC) and Indirect Adaptive Fuzzy Controller (IAFC) and a gradually activated supervisory controller. The unique feature of the HAFC is that no mathematical...
This paper presents an approach to shank-foot trajectory control using computed-torque control method. The aim is to provide rehabilitative measures to help patients with lower limb disorders improve their mobility performance. This measure is achieved by designing a desired trajectory to be followed by the shank-foot model for the rehabilitative purpose. The shank-foot model is designed to depict...
In this paper, the problem of trajectory optimization for robotic manipulators is solved by a newly developed methodology called Discrete Mechanics and Optimal Control (DMOC). This new methodology is based on the direct discretizaion of the Lagrange-d'Alembert principle. The constraints for the objective function to be optimized are the forced discrete Euler-Lagrange equations. In this paper, DMOC...
Modeling the passive behavior of the knee in subjects with spasticity involves the applied external torques (e.g. gravitational torque), the intrinsic moments due to tissue properties, as well as active, neurally defined moments resulting from the hypersensitivity of reflexes introduced by disability. In order to provide estimates of the necessary intrinsic terms in the equation of motion, the push-pull...
Biped robot locomotion is one of the most challenging fields in humanoid robots. Many gait generation models are introduced to have stable walking similar to human. One of the gait generation models is Central Pattern Generator (CPG) which can produce complex nonlinear oscillation as a pattern for walking. In this paper joints trajectories are calculated by using polynomial equations for the support...
A grinding robot is composed of six joints, within which the second joint is a prismatic joint and the others are rotational joints. According to its configuration characteristic, the 6DOF of the inverse kinematics problem was decomposed into two 3DOF sub-problems: the position inverse kinematics and the attitude inverse kinematics. Then the two sub-problems were respectively solved analytically,...
In this paper, a new control algorithm is presented for implementing hopping and balancing motions on a planar hopping machine with a single actuated revolute joint. Starting with a simple control algorithm for balancing, it is extended to perform trajectory-tracking maneuvers, which enables it to perform the crouching, lift-off and flight phases of a single hop, as well as re-balancing after landing...
Off-line dynamic identification requires the use of a model linear in relation to the robot dynamic parameters and the use of linear least squares technique to calculate the parameters. Most of time, the used model is the Inverse Dynamic Identification Model (IDIM). However, the computation of its symbolic expressions is extremely tedious. In order to simplify the procedure, the use of the Power Identification...
In last decades, interest in biped robots (specially humanoid robots) have been growing up. Stable Walking is one of the critical challenging problems in these kinds of robots and many researches have been done to achieve a walking model similar to human. Central Pattern Generator (CPG) is one of the biological gait generation models which can produce complex nonlinear oscillation as a pattern for...
Cloud federation is the next step in creating a new cloud computing ecosystem. The absence of suitable business models for federation managers is hindering the wide deployment of this critical feature. In this paper we will study existing federation managers, specifically CCFM (Cross-Cloud Federation Manager) and analyze its strengths and limitations. To overcome its limitations and make cloud federation...
In many cases of new actuation of compliant controlled or bio-inspired joint driven robot, a global identification of electrical and mechanical coupled dynamics is required. This paper proposes a technique which mixes a closed loop output error method with the inverse dynamic identification model method which allows using linear least-squares technique to estimate the parameters. A first approach...
This paper demonstrates that for certain choices of mass distribution and addition of springs, an underactuated degree-of-freedom (2-DOF) system is static feedback linearizable, i.e., differentially flat as well. This paper is original and provides a ground breaking study in underactuated dynamical systems.
In this paper, a nonlinear feedback controller is proposed for a single link flexible joint manipulator based on the concept of differential flatness. The control design is approached from the perspective of using input state feedback linearization via the flatness property of the robot. It is shown that the nonlinear dynamics of the manipulator satisfies the controllability and involutivity conditions...
In this research, an approach to optimize motions for a humanoids is presented. Rapidly-exploring Random Tree(RRT) were used to plan an initial suboptimal motion. A reinforcement learning was then implemented to optimize the trajectories with respect to energy consumption, similarity to a human's natural motion and, physical limits. Energy cost was estimated by joint torque from a dynamic model, and...
In this paper, the mathematical modeling and the application of a new trajectory tracking control technique for hydraulic-driven rigid-flexible manipulator are concerned. To get a closer dynamic behavior of the real system, both the flexible manipulator linkage and the actuator dynamics are considered. The exact dynamic model of flexible manipulator is derived using Lagrange principle and assumed...
This paper investigates when a 2 degree-of-freedom PRRRP closed-chain system with a single actuator is both strongly accessible and feedback linearizable. It is demonstrated that for certain choices of mass distribution and addition of springs, an under-actuated 2 DOF PRRRP system is static feedback linearizable, i.e., also differentially flat.
In this paper, we present the optimum objective function for snatch weightlifting using genetic algorithm optimization. Therefore, it would be possible to study snatch weightlifting more accurately, because the biomechanical parameters in this movement including the body trajectory and forces and torques acting in the joints, depend on the objective function. In this study, kinematics and dynamics...
The model of a single flexible-link robot arm with a payload attached to its tip is represented in a cascade-like fashion using a proper coordinate transformation of the system state. The new system representation makes possible to find a way to assign a convenient dynamics for the overall system to control its tip position by using the joint shaft angular position as a virtual control input for the...
The model of a single flexible-link robot arm with a payload attached to its tip is represented in a cascade-like fashion using a proper coordinate transformation of the system state. The new system representation makes possible to find a way to assign a convenient dynamics for the overall system to control its tip position by using the joint shaft angular position as a virtual control input for the...
Capture-the-flag is a complex, challenging game that is a useful proxy for many problems in robotics and other application areas. The game is adversarial, with multiple, potentially competing, objectives. This interplay between different factors makes the problem complex, even in the case of only two players. To make analysis tractable, previous approaches often make various limiting assumptions upon...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.