The goal of this study was to design a practical fuzzy controller of the cycle-to-cycle control for multi-joint movements of swing phase of functional electrical stimulation (FES) induced gait. First, we designed three fuzzy controllers (a fixed fuzzy controller, a fuzzy controller with parameter adjustment based on the gradient descent method, and a fuzzy controller with parameter adjustment b...

This paper addresses the impedance control problem for flexible joint manipulators. An impedance controller structure is proposed, which is based on an exact decoupling of the torque dynamics from the link dynamics. A formal stability analysis of the proposed controller is presented for the general tracking case. Preliminary experimental results are given for a single flexible joint.

Impedance control has been suggested as the strategy employed by the central nervous system to control human postures and movements. A realization of this strategy is presented that uses a model predictive control algorithm as a higher motor controller. External disturbances are explicitly included in the model. The combination of 3 key factors-joint impedance control, model predictive controll...

Most manipulator motion controllers require joint velocity feedback. Whenever joint velocities are not measurable, they are estimated from the joint positions. However, velocity estimates tend to be inaccurate under low-speed motion or low sensor resolution conditions. Moreover, velocity estimators may either be susceptible to model uncertainties or introduce additional dynamics (e.g., phase la...

The paper investigates the control of a three prismatic-prismatic-revolute (3 PPR) U-base planar parallel manipulator in the presence of parameter uncertainties and unknown disturbances. The 3PPR U-base planar parallel manipulator is a motion platform with singularity free workspace (bounded orientation angle θz ≤ ±90 ◦) and has manipulator legs located on the plane in association with a moving...

in this paper, new features of satellite configuration, such as ip network  based infrastructure and separated signaling and media  are considered to propose a variety of satellite configurations in different orbits. because of their  different altitude in space such as low earth orbit(leo) and geostationary orbit (geo). a test bed used to test call setup delay in a one space link to process th...

In this paper the design of an optimal nonlinear H∞ controller for flexible joint robot (FJR) is presented. An approximate solution based on Taylor Series expansion is considered for the Hamilton-Jacobi-Isaac (HJI) inequality. A two-degree-of-freedom controller combined of optimal nonlinear H∞ controller and inverse dynamics controller is proposed to tackle the regulation as well as tracking pr...

This paper introduces a robust task-space control scheme for a robotic system with an adaptive observer. The proposed approach does not require the availability of the system states and an adaptive observer is developed to estimate the state variables. These estimated states are then used in the control scheme. First, the dynamic model of a robot is derived. Next, an observer-based robust contr...

An adaptive sliding mode fault-tolerant controller based on fault observer is proposed for the space robots with joint actuator gain faults. Firstly, dynamic model of underactuated robot deduced combining conservation law linear momentum Lagrange method. Then, manipulator joints obtained by using mathematical operation block matrices, hence measurement angular acceleration base attitude can be ...