For efficient visual servoing of an “eye-in-hand” robot, the concepts of Augmented Image Space and Transformed Feature Space are presented in the paper. A formal definition of image features as functionals is given along with a technique to use defined image features for visual servoing. Compared with other known methods, the proposed concepts reduce the computational burden for visual feedback, and enhance the flexibility in describing the vision-based task. Simulations and real experiments demonstrate that the proposed concepts are useful and versatile tools for the industrial robot vision tasks, and thus the visual servoing problem can be dealt with more systematically.

In this paper, the problem of real-time computation of a dynamic model of manipulator is considered. In order to decrease the number of operations for dynamic model computation, an approximate model is introduced. Also, a relative error criterion is proposed, which enables one to determine the computing periods of various parts of a dynamic model of manipulator.

This paper presents a simple identification method of the actual kinematic parameters for a robot with parallel joints. It is known that Denavit–Hartenberg's coordinate System is not useful for nearly parallel joints. In this paper, the coordinate frames are reassigned to model the kinematic parameter between nearly parallel joints by four parameters. The proposed identification method uses a straight ruler about 1 m long. A robot hand is placed by using a teaching pendant at the prescribed points on the ruler, and the corresponding error function is defined. The identified kinematic parameters, which make the error function zero, are obtained by the iterative least square method based on the singular value decomposition. In the compensation of joint angles, only the position is considered because the usual applications of robot do not require a precise orientation control.

The 5-bar-linkage manipulator configuration is well suited to many industrial robotic applications. Aside from kinematic suitability, the dynamic equations are greatly simplified due to a decoupling of the manipulator inertia matrix. The design also lends itself to the use of direct drive motors. However, these motors must be capable of providing a high continuous torque to counter gravitational loading in the conventional manipulator design. In this paper, the static and dynamic design of the 5-bar-linkage manipulator is analysed. A technique is proposed whereby the motor torque requirements may be reduced to a fraction of those required in the conventional design, while simultaneously retaining the advantage of a decoupled inertia matrix. Details of a prototype manipulator and experimental results of its performance are presented.

By using very simple considerations related to the mechanical Lagrangian itself, one obtains a new general class of parameter adaptation algorithms for robot manipulators, which provides such approaches as PID adaptation schemes. These models could apply to random structural mechanical Systems, subject to the conditon that they are defined by Lagrangians.

This paper presents a general technique to model flexible components (mainly links and joints flexibilities are considered) of manipulator arms based on Castigliano's theorem of least work. The robotic arms flexibility properties are derived and represented by the matrix of compliance coefficients. Such expressions can be used to determine the errors due to the robotic tip deformations under the application of a set of applied loads at the tip in a Cartesian space. Once these deformations are computed, they may be used to correct for the positional errors arisen from the robotic structural deformations in the motion control algorithms.

A SCARA type direct-drive robot which can be used in the assembly operation of printed circuit boards was designed and manufactured with graphite fiber epoxy composite material. The optimum stacking angle of the graphite fiber which gives the minimum deflection of the composite robot arm was calculated by the energy method and the manufacturing method of the box-type cross section of the robot arm with composite materials was developed.

In order to compare the dynamic characteristics of the composite material robot arm with a conventional material robot arm, an aluminum robot arm which has the same dimensions and thickness of the composite robot arm was manufactured.

The static and dynamic characteristics of the composite material robot arm such as static deflection, natural frequency and damping as well as weight saving were considerably improved compared to those of the aluminum robot arm.

In this paper, an efficient method for computing the Jacobian matrix for robot manipulators on a single processor computer is developed. Compared with the existing methods, the number of required numerical operations is considerably smaller, making the proposed technique the fastest, or the least expensive, one for any general N degrees-of-freedom manipulator.

The paper presents an educational system for teaching and research in robotics which consists of a manipulator, controller and a PC compatible host computer. The advanced design of host-computer user-interface software makes the system very suitable for teaching. It allows the user not only to follow the system states but also to change the control structure on-line. In the first part of this paper the architecture of the system, window-oriented user interface, specially designed robot language and several build-in students lessons will be described as well as the data acquisition system and advanced graphical capabilities.

In the second part of this paper the executive controller architecture is described. Besides the manipulator control function and IO operations, the controller supports communication with the host-computer. The controller is programmable, i.e. it executes various tasks within user-defined and build-in students lessons. By the use of simple host-computer commands the controller can execute various algorithms both for trajectory generation and dynamically compensated digital servo control. The dynamic model components in the feed-forward and feed-back control loop can be selectively included and changed during the manipulator's motion. Experimental results with a 4-link educational robot are presented.