Force and acceleration sensor fusion for compliant manipulation control in 6 degrees of freedom

This paper focusses on sensor fusion in robotic manipulation: six-dimensional (6-D) force/torque signals and 6-D acceleration signals are used to extract forces and torques caused by inertia. As result, only forces and torques established by environmental contact(s) remain. Apart from an improvement of hybrid force/pose control behavior, an additional major benefit is that regular resetting/zeroing of force/torque sensors before free space/contact transitions can be omitted. All essential equations, transformations and calculations that are required for this 6-D fusion approach are derived. To highlight the meaning for practical implementations, numerous experiments with a six-joint Staeubli RX60 industrial manipulator are presented and the achieved results are discussed.     

抽水蓄能电站经济评价软件

抽水蓄能电站经济评价软件以MICROSOFTVISUALBASIC 5 0FORWINDOWS 9 X为开发工具 ,分为国民经济评价计算、财务评价计算及报表打印三大相对独立的功能模块。该软件实现了分析计算项目对国民经济的净效益、评价其经济合理性、分析计算项目直接发生的财务效益和费用、编制报表、判别项目的财务可行性等功能 ,界面友好 ,操作方便 ,计算成果准确。该软件目前已在水电系统内推广应用 ,效果良好     

Synthesized articulated behavior using space-temporal on-line principal component analysis

This paper presents a new framework to synthesize humanoid behavior by learning and imitating the behavior of an articulated body using motion capture. The video-based motion capturing method has been developed mainly for analysis of human movement, but is very rarely used to teach or imitate the behavior of an articulated body to a virtual agent in an on-line manner. Using our proposed applications, new behaviors of one agent can be simultaneously analyzed and used to train or imitate another with a novel visual learning methodology. In the on-line learning phase, we propose a new way of synthesizing humanoid behavior based on on-line learning of principal component analysis (PCA) bases of the behavior. Although there are many existing studies which utilize PCA for object/behavior representation, this paper introduces two criteria to determine if the dimension of the subspace is to be expanded or not and applies a Fisher criterion to synthesize new behaviors. The proposed methodology is well-matched to both behavioral training and synthesis, since it is automatically carried out as an on-line long-term learning of humanoid behaviors without the overhead of an expanding learning space. The final outcome of these methodologies is to synthesize multiple humanoid behaviors for the generation of arbitrary behaviors. The experimental results using a humanoid figure and a virtual robot demonstrate the feasibility and merits of this method.     

Vision based seam tracking system for underwater flux cored arc welding

Abstract

Manual underwater welding is usually time consuming, expensive and hard to perform because of the rigorous underwater environment. Automatic underwater welding can be performed faster at less cost and with higher quality. An automatic seam tracking system for underwater flux cored arc welding has been developed. It consists of a vision sensing module, a seam recognition module, a fuzzy controller (FC) and an X–Y travel platform. The vision sensing module can capture clear seam images during welding, successfully resolving the problem of welding arc interference during underwater flux cored arc welding. The seam recognition module filters, enhances and thresholds the seam images and then recognises the seam deviation angle with a three layer back propagation neural network. The FC outputs the control parameters according to the seam deviation angle and then controls the X–Y platform to drive the torch to the centre of the seam. In this study, three different welds were considered: a straight line, a kinked straight line and an S curved line. These welds were tracked real timely during underwater flux cored arc welding. The results show that this seam tracking system can meet the requirements of the automatic underwater flux cored arc welding.     

CAPP系统智能化的关键技术

提出智能化CAPP系统的关键技术以及解决方法,介绍智能推理的机制和一种新型的语言——VI-SUAL PROLOG语言。     

Determining penetration from topside weld bead and weld pool geometry in PGMAW

Abstract

Finding suitable characteristic parameters of topside weld pool to reflect the penetration is a key work in weld shape control. In this paper, by analysing the molten metal volume, the relationship between topside weld bead shape and penetration in pulsed gas metal arc welding (PGMAW) is revealed, and then several weld bead characteristic parameters (WBCPs) are proposed to determine the penetration. However, these WBCPs are difficult to be obtained in real time, because continuous solidifying of weld pool forms the weld bead, and the WBCPs can be reflected by the weld pool geometry. Therefore, some weld pool characteristic parameters (WPCPs) are proposed to replace the WBCPs. Furthermore, a visual system is established and a series of image processing arithmetics are developed to extract the WPCPs.     

智能控制分拣系统的研制

利用计算机技术对生产线上的分拣设备进行智能化控制是一种既能节约成本又能在短时间内提升企业生产效率的好方法.引入计算机图像处理技术对工件进行颜色分辨,能够有效地减少人为原因造成的判断失误.     

Through arc sensing in gas metal arc welding with signature images

Abstract

This work presents a new method for through the arc estimation of welding parameters in gas metal arc welding based on signature images. The method is generally applicable and makes use of a novel data fitting procedure. The work covers unassisted through the arc estimation, without auxiliary techniques such as welding head oscillation. The technique is demonstrated for both pulse and short circuiting welding, with estimation of position relative to an overlap joint and a narrow gap weld, and estimation of the width of a 'V' groove. The accuracy of the technique is affected by how closely the welding signatures match the fitting data and the signature image quality match provides a valuable check which shows when through the arc estimates cannot be relied on. Overall, the results demonstrate that through the arc measurements can have application in specialised situations, although accuracy is ultimately limited by phenomena that affect the arc and are not correlated with the measurement.     

The Colloquio Internazionale Sulla Scienza Della Fotografiaturin, 23–28 September 1963

Several derivatives of 7, 8-dihydroxybenzopyrylium chloride and of 7, 8-dihydroxycoumarin (daphne- tin) were synthesized and investigated as developing agents. They function best in the pH range 10-11, and possess similar photographic properties to pyrogallol, but show better keeping properties in solution. The best compounds are daphnetin, its 3-methyl derivative and its 3, 4-dimethyl derivative. These give higher speed for the same contrast than do catechol or metol.     

Vision-Based Task-Level Control of a Flexible-Link Manipulator

This paper discusses a vision-based approach to implement task-level control in flexible-link manipulators. The proposed approach emphasizes the advantage of using vision in the control of flexible manipulators. It is pointed out that taking advantage of the inherent robustness, implementation of an image-based visual servo can be regarded as a synthetic solution to precise task-level control of flexible manipulators. This approach is implemented in a three-dimensional flexible-link manipulator. The implementation makes good use of filters in decoupling task-level control and vibration suppression control. Moreover, we point out that although the robustness of the approach can help to overcome the difficulty in control resulting from the complex measurement of the link's elastic deformation, it lacks in capability of tip trajectory specification. This problem is analyzed in this research and it leads to the proposal for the integration of the image interpolation technique. This technique makes the proposed approach adequate for tasks involved with complex tip trajectories. For flexible-link manipulators, the proposed approach with the remedy is the first vision-based synthetic solution that attempts to make a flexible manipulator usable for a practical task.