Applied Mechanics and Materials Vol. 162

Abstract: This paper presents a prototype system for off-line programming of industrial robot RV-M1 using augmented reality technology. The system allows controlling a virtual model of the industrial robot co-located in the real environment, planning configurations, generating robot program and simulating the robot actions. The proposed architecture makes it possible to manipulate, pick or place the objects in the scene. The advantage of this system is use of inexpensive equipment for intuitive off-line programming of an industrial robot.

Abstract: Bone sawing skill demands a high level of dexterity from the surgeon that can be achieved only with a lot of training. Sawing is a basic skill required in many procedures, such as: osteotomy, ostectomy, amputation and arthroplasty surgery. Inefficient sawing can lead in orthognathic surgery to nerve lesion, bad split and non-union. Using virtual reality technology this complications can be reduced, by training the students on simulators until they assimilate the skill. This paper presents an early prototype for a bone sawing simulator in orthognathic surgery. A voxel-based mandible model obtained from a Computer Tomography is cut by removing the voxels that are inside the saw blade. The collision detection is based on hierarchical bounding volumes. The removal process is observed both visually and haptically.

Abstract: The author proposes a visual-servoing and vision-controlled robot. It claims no sensors installed or special control means used, instead of that a high-precision and high-speed 3D hand pose estimation permits real time operation with two cameras installed at positions of loosely orthogonal relationship, using one PC of the normal specifications. Two cameras have their own database. Once sequential hand images are recorded with these two high-speed cameras, the system first selects one database with bigger size of hand region in each recorded image. Second, a coarse screening is carried out according to the proportional information on the hand image which roughly correspond to wrist rotation, or thumb or finger extension. Third, a detailed search is performed for similarity among the selected candidates. The estimated results are transmitted to a robot so that the same motions of an operator is reconstructed in the robot without time delay.

Abstract: Based on Future Internet and ITIL, cutting edge concepts and approaches related to software service systems in distributed architectures for managing information and processes in industrial robot platforms are introduced. A new approach in defining the business relation for entities that have various interests related to industrial robots, as well as tools that support the new business approach are also identified in this paper. Further the architecture of a prototype platform designed around those concepts is presented.

Abstract: In this paper the authors propose some principles for the industrial robots performance evaluation. Also authors are searching similitudes between different industrial robots manufacturers in order to identify similitudes and underline the repeatability of certain performance indicators The indicators, which the authors are introducing, describe the performance parameters such as geometrical, kinematical and dynamical parameters. Also the paper searches for a non-dimensional solution preventing the measurement units based errors of evaluation. The quality scale is the classical one with one to ten notes.

Abstract: This paper deals with the design process of a particular mechatronic system: a tele-echography robot. First, we describe the principle of robotized tele-echography and the prototypes already designed. Then, after having chosen the design process, we show two medical gestures analysis performed to define the required specifications of a tele-echography robot. Several kinematic synthesis allow demonstrating that the serial spherical wrist is the most adapted structure to this medical application. The kinematic performance of this structure is limited by the singularity position located at the centre of the workspace. An inclined spherical wrist structure is proposed to displace the singularity position in a less used workspace zone that the normal direction to the patients skin. In the dimensional synthesis phase, this structure is optimized. Then, a collaborative design study with designers is presented to improve aesthetic and ergonomic of the robot. This step was very interesting because it brought innovative propositions. Finally, a detailed phase allows defining the PROSIT 1 robot. It was manufactured and will be soon tested in clinical environment.

Abstract: A main limitation of parallel kinematics machine tools (PKM) use for machining tasks is their accuracy low level mainly due to geometrical transformation errors. Indeed, such machine tools are geometrically controlled with an inverse kinematics model (IKM). For a large number of PKM, this IKM is defined with an analytic method and by introducing geometrical parameters. Thus, the influence of each geometrical parameter on the tool pose accuracy should be estimated via a sensitivity analysis. In the case of an overconstrained PKM, the IKM is generally computed with a numerical method. The sensitivity analysis leads to complex computation. The aim of this paper is to present a sensitivity analysis on the Tripteor X7, an overconstrained machine tool. This study is also a first step to define the geometrical identification method on this overconstrained mechanism.

Abstract: This paper proposes a simulation of a Stäubli TX90 robot based on SimMechanics Toolbox of Matlab. The goal is to predict the position and trajectory of its end-effector, with high reliability. The simulator takes into consideration loading, deformations, calibrated kinematic parameters, and all eventual sources of disturbance. An application to milling and a comparison between real and simulated data reveal the reliability and the accuracy of the simulator.

Abstract: Machine tools and robots have both evolved fundamentally and we can now question the abilities of new industrial robots concerning accurate task realization under high constraints. Requirements in terms of kinematic and dynamic capabilities in High Speed Machining (HSM) are increasingly demanding. To face the challenge of performance improvement, parallel and hybrid robotic architectures have emerged and a new generation of industrial serial robots with the ability to perform machining tasks has been designed. In this paper, we propose to evaluate the performance criteria of an industrial robot included in a kinematically redundant robotic cell dedicated to a machining task. Firstly, we present the constraints of the machining process (speed, accuracy etc.). We then detail the direct geometrical model and the kinematic model of a robot with closed chain in the arm and we propose a procedure for managing kinematic redundancy whilst integrating various criteria. Finally, we present the evolution of the criteria for a given trajectory in order to define the best location for a rotary table and to analyze the manipulators stiffness.

Abstract: Based on the relative positions of the parts to be assembled, positions imposed by the technological process of insertion, the conditions required to perform a predetermined operation have been defined. The relations that express the relative positions and orientations of the axes of the parts to be assembled have been determined. These expressions enable the establishment of the functional requirements imposed on the robot. We have taken into consideration the influence of robot accuracy on its positioning and orientation repeatability.