The aim of this study is to investigate the performance of a 6-DoF parallel robot in tracking the movement of the foot trajectory of a paretic leg during a single stride. The foot trajectories of nine patients with a paretic leg including both males and females have been measured and analysed by a Vicon system in a gait laboratory. Based on kinematic and dynamic analysis of a 6-DoF UPS parallel...

This paper describes a new structure of a six-DOF parallel robot. First, a known planar three-DOF double-triangular structure is modified by replacing the stationary triangle with a circle. It increases the work envelope considerably especially when rotational motions are required. The ability for unlimited rotational motion allows extending the structure into six-DOF by using two sets of stati...

In this paper, we propose a biped robot each of whose legs is composed of two 3-DOF parallel platforms that are linked serially. The thigh of each leg consists of a 3-DOF orientation platform and the shank consists of 3-DOF asymmetric parallel platform. The former consists of 3 active linear actuators and 7 passive joints. And the latter consists of two active linear actuators, one active rotat...

This paper studies inverse kinematics and dynamics of a new 4-DOF hybrid (serial-parallel) manipulator. This kind of hybrid manipulator is specially designed for pole/column climbing applications with spatially bent and branching poles/columns. The proposed hybrid manipulator consists of a one-DOF rotary mechanism in series with a 3-DOF planar 3-R PR parallel mechanism. This combination provide...

Parallel manipulators with a rotation-symmetric arm system possess all the typical advantages of parallel robots, such as high acceleration and high-accuracy positioning. Contrary to the majority of proposed parallel manipulators, the rotation-symmetric arm system leads to a large workspace in relation to the footprint of the manipulator. This paper focuses on a subclass of these manipulators w...

One of the most important approaches in the scientific research concerning the increase of the positioning accuracy is the use of parallel structures. Parallel kinematic structures have a series of advantages that makes them adequate for the mini-robots construction: actuator positioning on the seating, miniaturization, stiffness, positioning precision and repeatability, actuators separation fr...

Closed-form solutions were developed to optimize kinematics design of a 2-degree-of-freedom (2DOF) planar parallel manipulator. The optimum design based on the workspace was presented. Meanwhile, a global, comprehensive conditioning index was introduced to evaluate the kinematic designs. The optimal parallel manipulator is incorporated into a 5-DOF hybrid machine tool which includes a 2-DOF rot...

This paper presents the design and prototyping of a fully decoupled 3-DOF variable-configuration parallel manipulator with self-aligning called TRIFLEX. This parallel manipulator can change their form to carry out different tasks in different places, this change is managed by additional self-aligning degrees-of freedom. These degrees-of-freedom of self-aligning do not interfere in the motion of...

In this paper, the concept of a new 5-axis hybrid machine tool is proposed. The machine is a tool being with both parallel and serial structures, which is based on a novel 2-DOF parallel platform and serial orientations. The machine tool has advantages in terms of high stiffness, high dexterity, high speed, and being capable of long components manufacturing. The kinematics characteristics, such...