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...

A laparoscopic surgery system by using a robot holds many problems. Among these, its inability in delivering touching sensation to a surgeon is raised as the biggest problem. The current paper attempted to find a force feedback controlling method at the time of performing movement by using one-degree of freedom (DOF) arm of slave and master system that is used in the programming based system. T...

In this paper the trajectory planning problem is solved for a 2PRR parallel manipulator which works in cooperation with a 1 degree-of-freedom (dof) platform. The whole kinematic chain is considered as a redundant 3-dof manipulator, and an algorithm is presented to solve the redundancy by using the joint velocities in the null space of the jacobian matrix. The internal motion of the assisted man...

This paper reports a new 2-degree of freedom (2-dof) micromachined MEMS nanopositioner with the actuation and sensing elements on the same chip. The features of this new MEMS device are: its 2-dof (x-y axis) motion capability, the achievement of bi-directional movement (positive and negative displacement) along each axis thanks to the use of Z-shaped electrothermal actuators, and the measuremen...

Existing penalty-based haptic rendering approaches are based on the penetration depth estimation in strictly translational sense and cannot properly take object rotation into account. We propose a new six-degree-of-freedom (6-DOF) haptic rendering algorithm which is based on determining the closest-point projection of the inadmissible configuration onto the set of admissible configurations. Ene...

A finite-element deformable surface-spine model is developed in this paper to register two surfaces by recovering the nonlinear deformation with respect to each other. The deformable surface-spine model is a dynamic model governed by Lagrangian motion equations. A 9 degree-of-freedom (dof) finite-element surface element and a $-dof spine element are developed to iteratively solve Lagrangian equ...

This paper proposes a new family of spatial 3-DOF (degree of freedom) parallel manipulators with two translational and one rotational DOFs. The manipulators in this family are the variations of the parallel manipulators, which are capable of very high rotational capability, introduced by X.-J. Liu, J. Wang, and G. Pritschow (“A new family of spatial 3-DoF fully parallel manipulators with high r...

Recent work has proposed the reformulation of smoothness measures derived from standard integrated squared jerk, as a function of position, not time. However, its promulgation was in the context of monotonic excursion data extracted from single degree-of-freedom (DOF) movements; the result was a formulation of a phase smoothness measure with limited generalizability. Here, we present a complete...

NASA's latest anthropomorphic robot, Robonaut, has reached a milestone in its capability. This highly dexterous robot, designed to assist astronauts in space, is now performing complex tasks at the Johnson Space Center that could previously only be carried out by humans. With 43 degrees of freedom, Robonaut is the first humanoid built for space and incorporates technology advances in dexterous ...

This article presents a novel parallel spherical mechanism called Argos with three rotational degrees of freedom. Design aspects of the first prototype built of the Argos mechanism are discussed. The direct kinematic problem is solved, leading always to four nonsingular configurations of the end effector for a given set of joint angles. The inverse-kinematic problem yields two possible configur...