Time filter

Source Type

Meng Q.-X.,Shanghai University | Zhao Q.-J.,Shanghai University | Zhao Q.-J.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Tu D.-W.,Shanghai University | And 2 more authors.
Lecture Notes in Electrical Engineering | Year: 2017

In order to improve the efficiency and adaptability of 3-D laser sensor measurement system, this paper proposed a calibration method based on structural parameters for the 3-D laser sensor measurement system. In this method, by scanning and measuring the structural calibration target with known structural parameters, the models are established in the laser scanning coordinate system and inertial measurement sensor coordinate system respectively, and the linear features are extracted then solve out the relative position and attitude by the constrains of structural parameters. The calibration results are carried out on the 3-D measurement system, which is used to conduct a simulation measurement experiment. In the experiment, the measured results’ relative errors of lengths and angles of measured objects are less than 1.0 and 0.5 % on average, which indicate the accuracy of the calibration method. While the noise is increasing, the relative errors keep stability, which indicates the effectiveness of the calibration method. © Zhejiang University Press and Springer Science+Business Media Singapore 2017.

Xu S.,Shanghai University | Xu S.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Wang Y.,Shanghai University | Sun C.-K.,Shanghai University
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2016

The mission planning problem of a team of modular and reconfigurable robots (MRRs) in hospital service is studied. By analyzing and modeling, it is abstracted as a multidimensional combinatorial optimization problem with multiobjectives and multiconstraints. A population-based metaheuristic, the Improved Binary Bees Algorithm (IBBA), is proposed to optimize this NP-hard problem. The IBBA is featured as, 1) Functional partitioning and parallel implementation of global search and local search; 2) Integrating the methods of combinatorial schemes' expression and evolution, multiobjectives' handling and constraints' handing into the basic algorithm framework; and 3) Improving local search strategy from the prototype algorithm. Experiments are conducted with respect to a practical example. The IBBA exhibits feasibility, stability and advantages over its prototype algorithm in indices of solution quality, computational efficiency and single-objective optimization. Further, the advantages are interpretable from algorithm mechanisms. This study extends the field of research of MMR, and provides a general modeling method and optimization algorithm to solve general combinatorial optimization problems with multiobjectives and multiconstraints. © 2016, Chinese Institute of Electronics. All right reserved.

Liu Y.,Shanghai University | Liu Y.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Jiang C.,Shanghai University | Li S.,Shanghai University | And 2 more authors.
Journal of the Mechanical Behavior of Biomedical Materials | Year: 2016

While the field of tissue engineered vascular grafts has greatly advanced, many inadequacies still exist. Successfully developed scaffolds require mechanical and structural properties that match native vessels and optimal microenvironments that foster cell integration, adhesion and growth. We have developed a small diameter, three-layered composite vascular scaffold which consists of electrospun fibers and physically-crosslinked hydrogel with copper wire-induced grooves by combining the electrospinning and dip-coating methods. Scaffold morphology and mechanics were assessed, quantified and compared to native vessels. Scaffolds were seeded with Human Umbilical Vein Endothelial Cells (HUVECs), cultured in vitro for 3 days and were evaluated for cell viability and morphology. The results showed that composite scaffolds had adjustable mechanical strength and favorable biocompatibility, which is important in the future clinical application of Tissue-engineered vascular grafts (TEVGs). © 2016 Elsevier Ltd.

Shao H.,Shanghai University | Zhao Q.,Shanghai University | Zhao Q.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Tu D.,Shanghai University | Tu D.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics
Proceedings - 2014 International Conference on Intelligent Environments, IE 2014 | Year: 2014

In order to make the intelligent virtual classroom distinguish out the rotation direction of the user's head, a method for head behavior detection based on optical flow is proposed in this paper. Firstly, we select the key feature points of user's facial area. Then we calculate the user's head movement parameter through the data of feature points which have been recorded. Secondly, a kind of head direction sensing model has been provided for detecting the head identified parameters. Finally, according to the interaction mechanism of the interaction scenario, intelligent virtual classroom will respond to the user's head movement based on the result of the head direction judgment. By online tests, the results show that the method is of high recognition rate and quick real-time. © 2014 IEEE.

Zhao Q.,Shanghai University | Zhao Q.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Meng Q.,Shanghai University
Zhongguo Jiguang/Chinese Journal of Lasers | Year: 2015

In order to enhance the precision of the three-dimensional (3D) measurement system based on the laser sensors, an on-line calibration process based on structure parameter is proposed in this content. In this method, the structure object with known parameters is measured by the laser scanner, with its model being established within the laser scanner coordinate system and inertial measurement sensor coordinate system separately, and the linear feature on the scanned plane being extracted, then the relative position and orientation relationship is calculated with the constraint conditions of the structure parameters. The initial value calibration experiment is conducted on the 3D measurement system, then the initial values is used to conduct on-line calibration experiment, and the average relative error of measurement is below 0.9%, which means the calibration and measurement method is accurate and can adapt to different work conditions. © 2015, Science Press. All right reserved.

Yao Y.,Shanghai University | Yao Y.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Guo M.,Shanghai University
Jisuanji Fuzhu Sheji Yu Tuxingxue Xuebao/Journal of Computer-Aided Design and Computer Graphics | Year: 2014

In order to design controllable porous structures within mesh models, this paper presents a design method for assembling volumetric structures. Firstly, the mesh model is divided into a set of assembling subspaces. Secondly, the unit structures represented by implicit surfaces are assembled into the subspace and optimized with local rules. Finally, a mesh surface is extracted from the assembled parametric model to represent the internal structure of the model. Experimental results show that the method can generate the mesh model with gradient and smooth porous structures, avoiding possible errors brought about by performing a large number of Boolean operations.

Liu Y.,Shanghai University | Liu Y.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Xiang K.,Shanghai University | Chen H.,Shanghai University | And 3 more authors.
AIP Advances | Year: 2015

Composite vascular grafts formed by micro-imprinting and electrospinning exhibited improved mechanical properties relative to those formed by electrospinning alone. The three-layered composite grafts mimic the three-layered structure of natural blood vessels. The middle layer is made by micro-imprinting poly-p-dioxanone (PPDO), while the inner and outer layers are electrospun mixtures of chitosan and polyvinyl alcohol. The graft morphology is characterized with scanning electron microscopy. For constant graft thicknesses, the PPDO increases the mechanical strength. Cells cultivated on the vascular grafts adhere and proliferate better because of the natural, biological chitosan in the inner and outer layers. Overall, the composite scaffolds could be good candidates for blood vessel repair. © 2015 Author(s).

Feng D.,Shanghai University | Zhang X.,Shanghai University | Zhang X.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Chu W.,Shanghai University
Guangxue Jishu/Optical Technique | Year: 2016

In order to detect the motion range of an underwater manipulator, a multiple stereo vision measurement system is developed. By measuring the motion trajectory of the end of the manipulator, the actual rotation range of a joint measured angle can be calculated by spatial circle fitting algorithm. The key algorithm of the measurement system-spatial circle fitting algorithm is studied. First, spatial circle is the intersection of a plane and a sphere. Therefore, the center of spatial circle must be on the middle vertical plane of a line defined by two arbitrary points on the sphere. The middle vertical plan can be derived by spatial vector fitting method. Next, the equation of the spatial circle can be built by simultaneous equations of the middle vertical plan and the plane fitted. Further, the radius can be calculated by the center of fitting circle. Then, the wrong tracking points during the actual engineering measurement task are analyzed. The fitting result will be incorrect if all the measured points used for spatial fitting directly without excluding outliers, which will affect the correctness of the measurement results greatly. At last, a RANSAC (Random Sample Consensus)-based spatial circle fitting algorithm is proposed. The outliers can be excluded effectively from a set of measuring data through an iterative approach to estimate the parameters of mathematical model. Therefore, the correct fitting results can be guaranteed. The results of simulation and actual experiments show that the outliers can be removed successfully, if the percentage of outliers in all points is less than 20%, the correctness of the spatial circle fitting algorithm is nearly up to 100%. The proposed algorithm can solve the problem effectively while applying the measurement system to detect the motion range of a manipulator in the practical engineering application. © 2016, Editorial Board of Optical Technique. All right reserved.

He B.,Shanghai University | He B.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Tang W.,Shanghai University | Tang W.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | And 2 more authors.
International Journal of Advanced Manufacturing Technology | Year: 2014

Dynamics is concerned with the study of forces and torques and their effect on motion. As formulating the suitable dynamics models for an offshore crane is very crucial for analyzing the behavior and lightweight design, many researches have been focused on it in recent decades with a result of many valuable contributions. However, current researches always focus on rigid crane, while the crane is always a rigid-flexible coupling multibody system, which can affect the accuracy of dynamic analysis. This paper proposed a model of dynamics analysis of an offshore crane based on rigid-flexible coupling virtual prototyping. After the structure and performance parameters of the 800-ton offshore crane were introduced, rigid-flexible coupling virtual prototyping-based dynamics analysis and numerical simulation were then put forward. The dynamics experiment is carried out based on offshore crane physical prototyping, and experimental results indicate successful lifting load with predetermined boom angle, which demonstrates that the accuracy of the dynamics analysis is based on rigid-flexible coupling virtual prototyping. The design of an offshore crane is given as an example which demonstrates that the methodology is obviously helpful to offshore crane design. © 2014, Springer-Verlag London.

He R.C.,Shanghai University | He R.C.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics | Gu X.J.,Shanghai University | Gu X.J.,Shanghai Key Laboratory of Intelligent Manufacturing and Robotics
Advanced Materials Research | Year: 2014

As a new environmental-protection technology, large-scale ammonia-based Flue Gas Desulfurization (FGD) requires high control and process technology. The process of FGD almost includes all the operation units in chemical industry. In order to make the equipment adapt to some complex changes of original flue gas and operate on better work conditions like low energy consumption, optimum liquid/gas ratio, minimum water consumption, completely nitrites oxidization, the multivariable predictive control and soft sensor based on mechanism model are studied in this paper. And the results show that these problems of variables correlation, large delay and variables coupling of FGD are resolved. In addition, ammonia consumption is lower, by-products quality is improved, Besides, the process operation is more smooth and safe, so the equipment can run effectively and economically after carrying on advanced process control. © (2014) Trans Tech Publications, Switzerland.

Loading Shanghai Key Laboratory of Intelligent Manufacturing and Robotics collaborators
Loading Shanghai Key Laboratory of Intelligent Manufacturing and Robotics collaborators