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A new algorithm to determine the workspace of a robot manipulator is presented in this paper. The method is based on the concept of dividing the robot structure into a regional structure and an orientational structure and is much more efficient than many methods currently available. Another advantage is that the method is expedient to plot the contours of the workspace of a robot manipulator on an arbitrarily defined plane or determine the extreme points along a general direction. The problem of determining subspaces of different joint configurations is also addressed and a method to compute them is proposed. Since for an ordinary industrial robot the regional structure is usually solvable to the first three joint variables, the method proposed is efficient computationally. The applicability of the method is demonstrated by some numeric examples.

Since, for actual industrial robots, the kinematic models present certain inaccuracies due to a number of effects such as the mechanical tolerances, deformations of mechanical elements etc., the theoretic models must be modified to compensate the position and orientation errors. In this paper, methods of redeveloping the actual kinematic models and of compansating the theoretic models are presented. Besides, a simple method for calculation of the matrices of partial derivatives of the position and orienation vector with respect to link parameters vectors is also presented. Theoretically, the position and orientation errors due to the inaccuracy of link parameters can be eliminated by finding the actual joint coordinates. If the inverse kinematics of a robot has not closed-form solution, it's solved by numerical methods. We know that the selection of the initial point on iteration for a numerical iterative method is very important for the convergence and the converging velocity. In this paper, a reasonable selection for this point based on the analytic solution of a similar, but simpler robot, is proposed. According to this selection, the iterative procedure will almost always converge rapidly to a real solution within the physical joint ranges.

This paper deals with the various phases into which researches on vibromachines have been articulated over last years in many countries.

The path planning of the industrial robots is usually done in joint space to reduce the on-line computational amount. To do this, a sequence of Cartesian knots chosen carefully must be transformed into joint space. The joint trajectories are often interpolated by polynomial functions, usually by cubic splines. This paper presents a new method for joint trajectories approximation. The method requires to transform the positions, velocities and accelerations of the knots. It can reduce the number of needed points and consequently the total computational amount, and can realize the joint trajectories in real-time. A comparison to the usual cubic spline approach is shown by an illustrative example.

This paper deals with a new method for a continuous regulation of a vibratory machine oscillation amplitude, by acting only on the electronic equipment, which can be put at large distance from the machine.