In this paper, the computational problem of inverse kinematics of arm prehension movements was investigated. How motions of each joint involved in arm movements can be used to control the end-effector (hand) position and orientation was first examined. It is shown that the inverse kinematics problem due to the kinematic redundancy in joint space is ill-posed only at the control of hand orientat...

In order to analyse the maximum velocity of parallel maniprdators in operational space, a graphical method based on the analysis of the algebraic inequalities describing the constraints on the kinematics mode[ is presented. We consider a general 6 d. of parallel manipulator and assume that all articrdar velocities are bounded by the same limit. The method is then applied to the Conventional Ste...

A novel 3RPS-3SPR serial-parallel manipulator (S-PM) with 6 degree of freedoms (DOFs) is proposed in this paper. It includes a lower 3RPS parallel manipulator (PM) and an upper 3SPR PM. Its inverse kinematics, active forces and workspace are solved. First, the inverse displacement is solved in close form based on the geometrical and the dimensional constraints of this S-PM. Second, the 9×9 and ...

We have designed a micro parallel positioning platform with two translational motions and a rotational motion that can tilt through large angles. Combined with a laser source mounted on its own slide, the platform can be used to produce fully three-dimensional micro-scale components. We investigate the kinematics, workspace, Jacobian matrix, and singularities of this parallel mechanism, and ana...

Traditional kinematic analysis of manipulators, built upon a deterministic articulated kinematic modeling often proves inadequate to capture uncertainties affecting the performance of the real robotic systems. While a probabilistic framework is necessary to characterize the system response variability, the random variable/vector based approaches are unable to effectively and efficiently charact...

There are many possible ways of identifying the posture of a human character from a set of known positions. These methods differ in subtle but important ways. We propose an alternative method to the jacobian-based Inverse Kinematics, one which allows for simple calibration, allows for sensors slippage, and can take advantage of knowledge of the type of motion being performed. This approach give...

Robot frame compliance has a large negative effect on the global accuracy of the system when large external forces/torques are exerted. This phenomenon is particularly problematic in applications where the robot is required to achieve ultra-high (micron level) accuracy under very large external loads, e.g. in biomechanical testing and high precision machining. To ensure the positioning accuracy...

The subject of this paper is a special class of closedchain manipulators. First, we analyze a family of twodegree-of-freedom (dof) five-bar planar linkages. Two Jacobian matrices appear in the kinematic relations between the joint-rate and the Cartesian-velocity vectors, which are called the “inverse kinematics” and the “direct kinematics” matrices. It is shown that the loci of points of the wo...