Solid State Phenomena Vols. 166-167

Abstract: The parallel manipulators are multi-mobile planar or spatial mechanisms with two to six kinematical chains that connect two rigid bodies, generically named platforms. The parallel manipulator is a complex topological structure, having the joints of various types. The most frequently utilized joints are: the mono-mobile kinematical pairs (revolute R or prismatic), the bi-mobile cylindrical pairs C and the tri-mobile spherical pairs S. One of the most important problems in parallel manipulators kinematics is finding the solution of direct kinematics. The paper presents a new way for the calculation of mobility and a new method for the direct kinematics of parallel manipulators RSS type, which are driven by three actuators.

Abstract: In the first part of this paper, there are presented the computing relations for kinematic (getting the velocity and the accelerations) and kinetostatic (getting the reactions – force and moment from the links) of a plan mechanism which has five elements. In the second part of the paper, there is a three-dimensional model of the mechanism created of SolidWorks and the analysis of this mechanism motion using COSMOSMotion under SolidWorks, the goal is a comparison between the results that we obtained on analytical way and the ones from this program.

Abstract: The paper deals with a special class of robots, namely the hyper-redundant arm with continuum elements. First, the dynamic model of the tentacle arm during the motion toward the imposed position is analyzed. The dynamic model of the tentacle arm with continuum elements in conjunction with the electro-rheological fluid is discussed. Also, numerical simulations of the arm motion to the imposed target are presented.

Abstract: This paper presents a novel collision-free trajectory planner for mobile car-like robot navigation in an unknown extra-road environment subject to nonholonomic constraints. The environment is represented by a parking lot with real traffic conditions, this meaning that static and dynamic obstacles are to be taken into consideration. The final goal that must be fulfilled by the system is to find a free parking space for the vehicle and safely make the parking manoeuvre while simultaneously detect and avoid obstacles. The planner relies on the combination of the potential field method, the 3rd degree Bezier curves method and on the newly designed “look ahead trajectory predictions” method. The major advantages of this method are the very short calculation time and a continuous stable behaviour of the trajectory. The results presented demonstrate the capabilities of the proposed method for solving the collision-free path-planning problem.

Abstract: In the last period, the quality and productivity of arc welding operations increased more than ever, especially in the areas that require high technology, represented mainly by the aerospace and nuclear industry, which led naturally to automation and robotics welding operations. The paper proposes a fuzzy system for the establishing of the main control parameters (welding current and welding speed) function of two important input parameters (plate thickness and diameter of the non consumable tungsten electrode). In this way, one of the actual modeling techniques (fuzzy logic) can be extended in welding technologies as an alternative tool, being particularly attractive for automated and robotized welding processes.

Abstract: In the paper a very simple parallel robot intended for some celestial orientation applications (satellite dishes, sun trackers, cameras, telescopes etc.) is proposed. After describing the mechanism and its kinematics, the workspace and the presence of the singularities are studied. The dimensional optimization to maximize the workspace is described, taking into account the constraints due to telescopic leg lengths and transmission angles.

Abstract: The paper deals with the kinematics structures of the peripheral devices used in robotic welding systems. There are two categories of such devices: either manipulators for extending the working range of the existing robots or positioners for supporting the parts to be processed. In certain cases, the last ones are also turning the welding parts, contributing to the technological movement. Starting from the kinematics structures a series of these devices, some theoretical models as well as practically built machines on their basis are shown.

Abstract: Due to the globalization companies are forced to implement efficient processes. Automation is a chance to reduce costs especially for repeative tasks. But by now it causes high costs for companies to integrate robots especially in case of individual systems for specific tasks. Due to the changing goods and working spaces within logistic processes automated systems have to be developed with respect to the task. The universal control computes an inverse kinematic based on application based data, executes an efficient path-planning and collision detection. This approach results in decreased develop costs for system-integrators, decreased costs for service and maintenance as less expert know-how is necessary and it results in shorter integration time, less system-failure due to the usage of standard components.

Abstract: In the design process of mechatronic systems rapid control prototyping had became an indispensable method for developing and testing control strategies. The paper presents an approach using Matlab and dSpace platforms for implementing rapid control prototyping method. The advantages of using dSpace platform are shown. The method is applied in the design of a parallel robot with 6 DOF. The simulation and experimental results are presented and compared; also the advantages of using rapid control prototyping are presented.

Abstract: This paper describes the riding robot system named by "RideBot" which is a riding robot like as a horse. In order to simulate the riding motions, we developed the saddle mechanism which can generate 3 DOF motions including pitch, roll, and bounce movement, and also we controlled the riding motions and the intention of horseman. To generate the riding motions with the bodily sensation, we developed Novel Washout Filter and the algorithms for motion control. And also, we developed some health care service for the health care of horseman. A body state index was proposed that evaluates the personal health state from both the measured physiological variables and the surveyed questions. The physiological variables such as weight, blood pressure, heart rate variability (HRV), accelerated state photoplethysmograph(APG), body fat, and happiness index were measured by the specially designed bio-handle system and survey questions. The efficiency of the proposed ride robot is evaluated in the experiments