To make the problems of existing high requirements of calibration tools, complex global calibration process addressed for monocular multi-view visual measurement system during measurement, in the paper, a global calib...To make the problems of existing high requirements of calibration tools, complex global calibration process addressed for monocular multi-view visual measurement system during measurement, in the paper, a global calibration method is proposed for the geometric properties of rotational correlation motion and the absolute orientation of the field of view without over lap. Firstly, a dual-camera system is constructed for photographing and collecting the rotating image sequence of two flat targets rigidly connected by a long rod at different positions, and based on the known parameters, such as, target feature image, world coordinates, camera internal parameters and so on, then the global PnP optimization method is used to solve the rotation axis and the reference point at different positions;Then, the absolute orientation matrix is constructed based on the parameters of rotation axis, reference point and connecting rod length obtained by this method. In the end, the singular value decomposition method is used to find the optimal rotation matrix, and then get the translation matrix. It’s shown based on simulation and actual tests that in comparison with the existing methods, the maximum attitude and pose errors is 0.0083˚ and 0.3657 mm, respectively, which improves the accuracy by 27.8% and 24.4%, respectively. The calibration device in this paper is simple, and there are no parallel, vertical and coplanar requirements between multiple rotating positions. At the same time, in view of the calibration accuracy, the accuracy requirements of most application scenarios can be met.展开更多
Most existing formation control approaches for Unmanned Aerial Vehicle(UAV)swarm assume that global position and global coordinate frame are directly available for each agent.To extend the application domain,this pape...Most existing formation control approaches for Unmanned Aerial Vehicle(UAV)swarm assume that global position and global coordinate frame are directly available for each agent.To extend the application domain,this paper proposes a distributed bearing-based formation control scheme,without any reliance on global position or global coordinate frame.The interactions among UAVs are described by a directed topology with two-leader structure.To address the issue of unavailable global coordinate frame,we first present a distributed orientation estimation law for each UAV to determine its orientation under the coordinate frame of the first leader.Based on the orientation estimation,we then design a bearing-based formation control law to globally asymptotically track target moving formations.Finally,simulation results are provided to validate the proposed method,which show that the translation,scale and orientation of the formation can be flexibly controlled via two leaders.展开更多
This paper reflects upon a wide range of strategies focused on increasing sustainability of urban design beyond and within the scope of individual buildings.By examining the case study of the Australian city of Newcas...This paper reflects upon a wide range of strategies focused on increasing sustainability of urban design beyond and within the scope of individual buildings.By examining the case study of the Australian city of Newcastle,the paper provides a context for a general debate about the urban design of a sustainable city centre,and discusses how urban design is affected(and can be expected to be even more affected in future)by the new paradigms of ecology.In this context,the author presents the case study of‘SolarCity’,which is based on a vision for the revitalisation of Newcastle’s city centre.It is an in-progress research and demonstration project,involving Australian and German architects,engineers and industry partners.It deals with cross-cutting issues in architecture and urban design and addresses the question:How to best cohesively integrate all aspects of energy systems,transport systems,waste and water management,climatisation,etc.,into contemporary urban design and the environmental performance of eco-buildings?The‘SolarCity’project encapsulates a vision based on the belief that urban revitalisation can be achieved and facilitated through the use of sustainable urban design principles.Consequently,this paper addresses the fundamentals of urban sustainability,such as orientation to the sun,and general strategies for more compact communities.As we begin to fully understand the consequences of our dependency on fossil energy and the automobile,the cost of mobility,and ways to integrate sustainability systems into buildings,it becomes apparent that the common knowledge of aesthetics of urban composition is no longer sufficient.展开更多
This paper describes the operational issues and basic technical requirements of modern aerial photogrammetry. The accuracy of photogrammetric point determination and the y-parallax at corresponding model points is ana...This paper describes the operational issues and basic technical requirements of modern aerial photogrammetry. The accuracy of photogrammetric point determination and the y-parallax at corresponding model points is analyzed when stereo models are reconstituted by using the exterior orientation elements of aerial images. Real aerial photographs, at image scales from 1:2 500 to 1:6 0000, with DGPS/IMU data taken from various topographies in China were processed by our POS-supported bundle block adjustment program WuCAPS. The empirical results verified that the accuracy of the exterior orientation elements from bundle block adjustment meets the requirements of the specifications of topographic mapping. However, the accuracy of the exterior orientation elements determined by POS fails to meet the requirements of the specifica- tions of topographic mapping.展开更多
The paper summarizes three major problems in the development of global librarianship,including physical space,development orientation and social competition,and three major challenges respectively concerning technolog...The paper summarizes three major problems in the development of global librarianship,including physical space,development orientation and social competition,and three major challenges respectively concerning technology,service and management.展开更多
文摘To make the problems of existing high requirements of calibration tools, complex global calibration process addressed for monocular multi-view visual measurement system during measurement, in the paper, a global calibration method is proposed for the geometric properties of rotational correlation motion and the absolute orientation of the field of view without over lap. Firstly, a dual-camera system is constructed for photographing and collecting the rotating image sequence of two flat targets rigidly connected by a long rod at different positions, and based on the known parameters, such as, target feature image, world coordinates, camera internal parameters and so on, then the global PnP optimization method is used to solve the rotation axis and the reference point at different positions;Then, the absolute orientation matrix is constructed based on the parameters of rotation axis, reference point and connecting rod length obtained by this method. In the end, the singular value decomposition method is used to find the optimal rotation matrix, and then get the translation matrix. It’s shown based on simulation and actual tests that in comparison with the existing methods, the maximum attitude and pose errors is 0.0083˚ and 0.3657 mm, respectively, which improves the accuracy by 27.8% and 24.4%, respectively. The calibration device in this paper is simple, and there are no parallel, vertical and coplanar requirements between multiple rotating positions. At the same time, in view of the calibration accuracy, the accuracy requirements of most application scenarios can be met.
基金supported by the National Science and Technology Major Project,China(No.2017-V-0010-0060)the National Natural Science Foundation of China(No.51620105010,51805026,51675019)+1 种基金the National Basic Research Program of China(No.JCKY2018601C107)China Scholarship Council(No.201906020030).
文摘Most existing formation control approaches for Unmanned Aerial Vehicle(UAV)swarm assume that global position and global coordinate frame are directly available for each agent.To extend the application domain,this paper proposes a distributed bearing-based formation control scheme,without any reliance on global position or global coordinate frame.The interactions among UAVs are described by a directed topology with two-leader structure.To address the issue of unavailable global coordinate frame,we first present a distributed orientation estimation law for each UAV to determine its orientation under the coordinate frame of the first leader.Based on the orientation estimation,we then design a bearing-based formation control law to globally asymptotically track target moving formations.Finally,simulation results are provided to validate the proposed method,which show that the translation,scale and orientation of the formation can be flexibly controlled via two leaders.
文摘This paper reflects upon a wide range of strategies focused on increasing sustainability of urban design beyond and within the scope of individual buildings.By examining the case study of the Australian city of Newcastle,the paper provides a context for a general debate about the urban design of a sustainable city centre,and discusses how urban design is affected(and can be expected to be even more affected in future)by the new paradigms of ecology.In this context,the author presents the case study of‘SolarCity’,which is based on a vision for the revitalisation of Newcastle’s city centre.It is an in-progress research and demonstration project,involving Australian and German architects,engineers and industry partners.It deals with cross-cutting issues in architecture and urban design and addresses the question:How to best cohesively integrate all aspects of energy systems,transport systems,waste and water management,climatisation,etc.,into contemporary urban design and the environmental performance of eco-buildings?The‘SolarCity’project encapsulates a vision based on the belief that urban revitalisation can be achieved and facilitated through the use of sustainable urban design principles.Consequently,this paper addresses the fundamentals of urban sustainability,such as orientation to the sun,and general strategies for more compact communities.As we begin to fully understand the consequences of our dependency on fossil energy and the automobile,the cost of mobility,and ways to integrate sustainability systems into buildings,it becomes apparent that the common knowledge of aesthetics of urban composition is no longer sufficient.
基金Supported by the National Natural Science Foundation of China （No. 40771176, 40721001）, the Program for New Century Excellent Talents in University （No. NCET-04-0662）.Acknowledgement The experiment data acquisition are supported by Institute of Remote Sensing Applications Chinese Academy of Sciences, Zhong Fei General Aviation Company, Liaoning Jingwei Surveying ＆ Mapping Technology INC, Dalian Urban Surveying Design Institute, Siwei Aviation Remote Sensing Co. Ltd., Xi＇an National surveying ＆ Mapping Aviation Remote Sensing Co. Ltd and so on. These supports are gratefully acknowledged. The author would like to express his hearty gratitude to Fu Jianhong, Xie Chou, Ji Shunping and Yang Ming for participating in partial experiments. The author would like to thank Yang Ming and professor Zhang Jingxiong for their polishing in English.
文摘This paper describes the operational issues and basic technical requirements of modern aerial photogrammetry. The accuracy of photogrammetric point determination and the y-parallax at corresponding model points is analyzed when stereo models are reconstituted by using the exterior orientation elements of aerial images. Real aerial photographs, at image scales from 1:2 500 to 1:6 0000, with DGPS/IMU data taken from various topographies in China were processed by our POS-supported bundle block adjustment program WuCAPS. The empirical results verified that the accuracy of the exterior orientation elements from bundle block adjustment meets the requirements of the specifications of topographic mapping. However, the accuracy of the exterior orientation elements determined by POS fails to meet the requirements of the specifica- tions of topographic mapping.
文摘The paper summarizes three major problems in the development of global librarianship,including physical space,development orientation and social competition,and three major challenges respectively concerning technology,service and management.
