Improving Machining Accuracy for a Robotic Arm with Hybrid Kinematic Chains Based on Deformation Characteristics

The joint deformation has great influence on machining accuracy for a robotic arm. In this paper, the deformation characteristics of the robotic arm with hybrid kinematic chains is investigated in order to improve its machining accuracy. Firstly, the deformation model of the joints has been established based on the Strain energy method and Castigliano theorem according to the robot structure. Secondly, the deformation influence coefficient (DIC) is defined to investigate the deformation influence of main components on the end-effector, and the deformation characteristics are evaluated by the simulation. Finally, a small size robotic arm prototype is established and robotic drilling comparative experiments are conducted. The theoretical and experiment results show that the machining method can be selected according to the DIC, which the force can be applied to the components with better stiffness. On the other hand, the deformation of driving components can also be reduced when the DIC cannot be adjusted to meet the accuracy requirement.

Application of Artificial Intelligence and Collaborative Knowledge for Manufacturing Design

With the rapid development of science and technology, digital technology has brought the world economy and management into a new stage. Collaborative design can realize product design process by cross-regional and cross-industry designers and share and exchange product information through network. With the rapid development of big data and artificial intelligence, knowledge services have gradually developed into multirole collaborative design activities based on artificial intelligence decision support. Traditional manufacturing industry has gradually transformed into modern manufacturing service industry after integrating information technology means such as Internet, communication, computer, and modern management methods. This article focuses on artificial intelligence decision support systems and the complex product manufacturing industry. We present a detailed analysis of how to integrate the knowledge generated by the product life cycle in the era of big data. We calculate the influence coefficient and sensitivity index of four different industries and propose a metadata architecture to improve the value of products as a whole. The findings of the research study imply that a knowledge-based collaborative platform should be designed by the enterprises and industries and a platform-based construction approach for economical, practical, and reliable production. We also present a detailed discussion about other factors such as the network cost of symmetric services, raw data and forecast data, and the number of nodes and the processing complexity.

Ski Tourism: A Case Study as a Booster for the Economic Development of Chongli, in China

Chongli, an internationally renowned ski mecca, is famous for hosting the 2022 Winter Olympics. As a booster of local economic development, ski tourism facilitates Chongli in moving away from poverty, and provides a new model for the economic development of other impoverished areas in China. The aim of this research is to analyze the impact of ski tourism in Chongli on local economic development in detail, to clarify the relationship between ski tourism and its related industries, and propose improvement measures, using the methods of the literature review, Delphi and investigation. This paper presents a detailed analysis of indicators which reflect ski tourism and its economic development, and calculates the degree of influence of skiing tourism on local economic development. The results show that, except for transportation, storage and postal services, the local economy of Chongli is positively affected by the income of ski tourism and the number of ski tourists. The influence coefficient of ski tourism has exceeded the average level of social influence. Based on the place of ski tourism in Chongli, some strategies, such as extending the industrial chain and improving product quality to strengthen the economic impact of ski tourism, are proposed.

Experimental Investigation on the Influence of Ambient Temperature on the Test Accuracy for the Differential Pressure Hydrostatic Levelling System

Hydrostatic levelling system (HLS) is widely used to monitor the settlement of major projects, such as high-speed railways, bridges, tunnels, dams, and nuclear power plants; ambient temperature is the most important influencing factor in the actual engineering settlement detection process. In order to systematically study the influence of ambient temperature TA on the test accuracy of the HLS, a test platform was built in the ambient temperature laboratory, and the influence of factors, including the amount of TA change, the rate of increase/decrease of TA, the expansion coefficient of the connecting pipe, and the distance of the measuring point, on the HLS test accuracy was quantitatively analyzed. The test results show that the elevation of a single HSL case has a linear correlation with the ambient temperature; when the temperature rise rate is greater than 0.1°C/min, the measured data are distorted due to incomplete development of material expansion. The temperature influence coefficient of a single HSL case is linearly related to the expansion coefficient deviation between the refrigerant and pipe; the test error of the double HLS case caused by TA is attributed to the expansion coefficient deviation of the pipe and the refrigerant between the base station and the measuring point. The relative temperature influence coefficient increases as distance measurement increases, and the HLS test error caused by TA will maintain a constant value when the distance measurement exceeds a certain value.

Analisis Manajemen Mitigasi Terhadap Sikap Masyarakat Dalam Pencegahan Banjir di Kelurahan Mustika Jaya Bekasi Jawa Barat

This study studies and at the same time has succeeded in proving that there is a significant influence of the role of mitigation management on variations in changes in community attitudes in terms of flood disaster mitigation in the Mutiara Gading Timur, Mustika Jaya sub-district, Bekasi. The role is partially proven and significantly influential, which is indicated by the influence coefficient of 0.496. By using a sample of 98 respondents and using a simple SEM analysis method, where the data is processed by the SMART PLS application. So if you look at these facts, it is hoped that in terms of translating the managerial implications, it is to always pay attention to the mitigation management system and structure as well as the consistent implementation of improving the quality of collegial collective community management, in this case, is to increase efforts to improve community attitudes in the mitigation process so that all efforts in anticipating flood disasters in the Mustika Jaya Bekasi area can take place well. Abstrak Studi ini mempelajari dan sekaligus telah sukses membuktikan bahwa terdapat pengaruh yang signifikan dari peran manajemen mitigasi terhadap variasi perubahan sikap masyarakat dalam hal mitigasi bencana banjir di kompleks Mutiara Gading Timur kelurahan Mustika Jaya Bekasi. Peran tersebut baik secara parsial terbukti dan signifikan cukup berpengaruh, yang ditunjukkan oleh koefisien pengaruh sebesar 0.496. Dengan menggunakan sampel sebesar 98 responden dan menggunakan metode analisis SEM sederhana, dimana data diolah oleh aplikasi SMART PLS. Sehingga bila melihat fakta tersebut diharapkan dalam hal menerjemahkan implikasi manajerialnya adalah untuk senantiasa memperhatikan sistem dan struktur manajemen mitigasi serta implementasi konsisten atas perbaikan kualitas manajemen masyarakat kolektif kolegial dalam hal ini adalah meningkatkan upaya perbaikan sikap masyarakat dalam proses mitigasi sehingga seluruh upaya dalam hal mengantisipasi bencana banjir dikawasan Mustika Jaya Bekasi bisa berlangsung dengan baik.

Field classification of fractured reservoirs of crystalline basement

Development of oil and gas deposits in fractured reservoirs entails certain risks due to peculiarities of geological structure. Classification and identification of fractures in reservoirs is of high-priority importance and makes it possible to assess the impact of both fractured systems and matrix blocks on field development parameters. This article presents the results of statistical and qualitative analysis of the influence of fracture systems and fracture heterogeneity to classify reservoirs in crystalline basement granitoids using the example of the White Tiger (Bach Ho) and Dragon (Rong) fields located on the southern shelf of the South China Sea (Viet Nam). Field classification of fractured reservoirs is based on a well-marked difference in parameters between wells within a field, due to fracture heterogeneity. In order to solve the tasks set, construction and analysis of graphs of well performance parameters distribution (productivity, flow rates, accumulated indicators, etc.) as well as Lorenz curves were carried out. According to the results, all the objects under study are characterized by asymmetrical shape of distribution curves, which indicates a significant influence of fracturing. Based on the calculated values of the fracture influence coefficient, it is found that fractured reservoirs in crystalline basement, as a first approximation, belong to type 2. This fact is inconsistent with the earlier works on crystalline basement, in which rocks are classified as reservoirs of type 1. Such contradiction is explained by the fact that the microfracture systems and the blocky low-permeability part exhibit matrix properties, but are not fully matrix. This part of the reservoir is proposed to be called a “pseudo-matrix”. If macrocracks dominate in the section, the basement rocks are identified as type 1 fractured reservoirs, but if microfracture systems (“pseudo-matrix”) dominate in some parts of the void space, they may show the properties of type 2 reservoirs forming a mixed type of fractured reservoirs.

A Dynamic-Balancing Testing System Designed for Flexible Rotor

In this paper, a dynamic-balancing testing system is designed. The innovative feature of the testing system is the dynamic balancing of the rotor system with robustness and high balance efficiency which meets the requirements of engineering application. The transient characteristic-based balancing method (TCBM) interface and the influence coefficient method (ICM) interface are designed in the testing system. The TCBM calculates the unbalance by the transient vibration responses while accelerating rotor operating without trail-weight. The ICM calculates the unbalance by the steady-state vibration responses while the rotor system operates with trail-weight and constant speed. The testing system has the functions of monitoring operations synchronously, measuring and recording the required vibration responses, analyzing the dynamic characteristics, and identifying the unbalance parameters. Experiments of the single disc rotor system are carried out, and the maximum deflection of the measuring point has decreased by 73.11% after balancing by the TCBM interface. The maximum amplitude of the measuring point at 2914 r/min has decreased by 77.74% after balancing by ICM interface, while the maximum deflection during the whole operation has decreased by 70.00%. The experiments prove the effectiveness of the testing system, while the testing system has advantages of convenient and intuitive operation, high balance efficiency, and security.

A computationally efficient engineering aerodynamic model for swept wind turbine blades

In this work, a computationally efficient engineering model for the aerodynamics of swept wind turbine blades is proposed for the extended blade element momentum (BEM) formulation. The model is modified based on a coupled near- and far-wake model, in which the near-wake is assumed to be the first quarter revolution of the non-expanding helical wake of the own blade. For the special case of in-plane trailed vorticity, the original empirical equations determining the steady-state value of the near-wake induction are replaced by the analytical results, which are in the form of incomplete elliptic integrals. For the general condition of helical trailed vorticities, the steady-state near-wake induction is approximated based on the results of the special conditions and a correction factor. The factor is calculated using empirical equations with influence coefficient tensors, to minimize the computational efforts. These influence coefficient tensors are pre-calculated and are fitted to the results from the numerical integration of the Biot-Savart law. With the indicial function approach, it is not necessary to explicitly save the information of the vorticities that were trailed in the previous time steps. This engineering approach is a combination of analytical results and numerical approximations, with low and constant computational effort for each time step. The proposed model is practically applicable to time-marching aero-servo-elastic simulations. The results of the swept blades with uniform inflow perpendicular to the rotor calculated from the proposed model are compared with the results from a BEM code, a lifting-line solver as well as a Navier-Stokes solver. The significantly improved agreement with the higher-fidelity models compared to the BEM method highlights the performance of the proposed method.