A land vehicle tracking and monitoring system based on the integration of differential global position system (DGPS), dead-reckoning (DR), and map matched technology is studied. In this paper, from the economic point ...A land vehicle tracking and monitoring system based on the integration of differential global position system (DGPS), dead-reckoning (DR), and map matched technology is studied. In this paper, from the economic point of view, a new scheme using the one-way directional communication link, is presented. Moreover, 8-state Kalman filter is proposed for integrated DGPS/DR system. When field tests are carried out using two C/A code GARMIN GPS receiver, the positioning accuracy less than 5 m (1σ) is achieved.展开更多
Plenty of dams in China are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and inanitions.The dam safety inspection remotely operated vehicle(...Plenty of dams in China are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and inanitions.The dam safety inspection remotely operated vehicle(DSIROV) is designed to solve these problems which can be equipped with many advanced sensors such as acoustical,optical and electrical sensors for underwater dam inspection.A least-square parameter estimation method is utilized to estimate the hydrodynamic coefficients of DSIROV,and a four degree-of-freedom(DOF) simulation system is constructed.The architecture of DSIROV's motion control system is introduced,which includes hardware and software structures.The hardware based on PC104 BUS,uses AMD ELAN520 as the controller's embedded CPU and all control modules work in VxWorks real-time operating system.Information flow of the motion system of DSIROV,automatic control of dam scanning and dead-reckoning algorithm for navigation are also discussed.The reliability of DSIROV's control system can be verified and the control system can fulfill the motion control mission because embankment checking can be demonstrated by the lake trials.展开更多
GPS/Dead-reckoning navigation system for autonomous underwater vehicle (AUV) is introduced, which includes navigation overall architecture, hardware and software structure. Dead-reckoning theory is presented in detail...GPS/Dead-reckoning navigation system for autonomous underwater vehicle (AUV) is introduced, which includes navigation overall architecture, hardware and software structure. Dead-reckoning theory is presented in details. And the strong tracking Kalman filter and Singer model are applied to handle the imprecise navigation mode, which can improve the navigation system’s precision and reliability. Finally, the sea experiments which include autonomous search mission in an unknown area and long distance motion are conducted to demonstrate the reliability and feasibility of the navigation system.展开更多
With the development of micro-electromechanical systems(MEMS), miniaturized, low-power and low-cost inertial measurement units(IMUs) have been widely integrated into mobile terminals and smart wearable devices. This p...With the development of micro-electromechanical systems(MEMS), miniaturized, low-power and low-cost inertial measurement units(IMUs) have been widely integrated into mobile terminals and smart wearable devices. This provides the prospect of a broad application for the inertial sensor-based pedestrian dead-reckoning(IPDR) systems. Especially for indoor navigation and indoor positioning, the IPDR systems have many unique advantages that other methods do not have. At present, a large number of technologies and methods for IPDR systems are proposed. In this paper, we have analyzed and outlined the IPDR systems based on about 80 documents in the field of IPDR in recent years. The article is structured in the form of an introduction-elucidation-conclusion framework. First, we proposed a general framework to explore the structure of an IPDR system. Then, according to this framework, the IPDR system was divided into six relatively independent sub-problems, which were discussed and summarized separately. Finally, we proposed a graph structure of IPDR systems, and a sub-directed graph, formed by selecting a combined path from the start node to the end node, skillfully constitutes a technical route of one specific IPDR system. At the end of the article, we summarized some key issues that need to be resolved before the IPDR systems are widely used.展开更多
Orientation update message filtering is an important issue in collaborativevirtual environments (CVEs). Dead-reckoning (DR) is a known effective mechanism for update messagefiltering. Yet, previous dead-reckoning tech...Orientation update message filtering is an important issue in collaborativevirtual environments (CVEs). Dead-reckoning (DR) is a known effective mechanism for update messagefiltering. Yet, previous dead-reckoning techniques mainly focus on the update message filtering forpositions. The existing orientation dead-reckoning algorithms are based on fixed threshold values.The drawbacks of fixed thresholding for orientations (FTO) are discussed in this paper. We propose avariable thresholding for orientations (VTO) based on average recent angular velocity. The mainadvantage of the proposed VTO is the ability of balancing the number of state update messages andshift frequency of direction and speed of rotation.展开更多
文摘A land vehicle tracking and monitoring system based on the integration of differential global position system (DGPS), dead-reckoning (DR), and map matched technology is studied. In this paper, from the economic point of view, a new scheme using the one-way directional communication link, is presented. Moreover, 8-state Kalman filter is proposed for integrated DGPS/DR system. When field tests are carried out using two C/A code GARMIN GPS receiver, the positioning accuracy less than 5 m (1σ) is achieved.
基金Project(20100480964) supported by China Postdoctoral Science FoundationProjects(2002AA420090,2008AA092301) supported by the National High Technology Research and Development Program of China
文摘Plenty of dams in China are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and inanitions.The dam safety inspection remotely operated vehicle(DSIROV) is designed to solve these problems which can be equipped with many advanced sensors such as acoustical,optical and electrical sensors for underwater dam inspection.A least-square parameter estimation method is utilized to estimate the hydrodynamic coefficients of DSIROV,and a four degree-of-freedom(DOF) simulation system is constructed.The architecture of DSIROV's motion control system is introduced,which includes hardware and software structures.The hardware based on PC104 BUS,uses AMD ELAN520 as the controller's embedded CPU and all control modules work in VxWorks real-time operating system.Information flow of the motion system of DSIROV,automatic control of dam scanning and dead-reckoning algorithm for navigation are also discussed.The reliability of DSIROV's control system can be verified and the control system can fulfill the motion control mission because embankment checking can be demonstrated by the lake trials.
文摘GPS/Dead-reckoning navigation system for autonomous underwater vehicle (AUV) is introduced, which includes navigation overall architecture, hardware and software structure. Dead-reckoning theory is presented in details. And the strong tracking Kalman filter and Singer model are applied to handle the imprecise navigation mode, which can improve the navigation system’s precision and reliability. Finally, the sea experiments which include autonomous search mission in an unknown area and long distance motion are conducted to demonstrate the reliability and feasibility of the navigation system.
基金supported by National Key Research and Development of China (No. 2017YFB1002800)
文摘With the development of micro-electromechanical systems(MEMS), miniaturized, low-power and low-cost inertial measurement units(IMUs) have been widely integrated into mobile terminals and smart wearable devices. This provides the prospect of a broad application for the inertial sensor-based pedestrian dead-reckoning(IPDR) systems. Especially for indoor navigation and indoor positioning, the IPDR systems have many unique advantages that other methods do not have. At present, a large number of technologies and methods for IPDR systems are proposed. In this paper, we have analyzed and outlined the IPDR systems based on about 80 documents in the field of IPDR in recent years. The article is structured in the form of an introduction-elucidation-conclusion framework. First, we proposed a general framework to explore the structure of an IPDR system. Then, according to this framework, the IPDR system was divided into six relatively independent sub-problems, which were discussed and summarized separately. Finally, we proposed a graph structure of IPDR systems, and a sub-directed graph, formed by selecting a combined path from the start node to the end node, skillfully constitutes a technical route of one specific IPDR system. At the end of the article, we summarized some key issues that need to be resolved before the IPDR systems are widely used.
文摘Orientation update message filtering is an important issue in collaborativevirtual environments (CVEs). Dead-reckoning (DR) is a known effective mechanism for update messagefiltering. Yet, previous dead-reckoning techniques mainly focus on the update message filtering forpositions. The existing orientation dead-reckoning algorithms are based on fixed threshold values.The drawbacks of fixed thresholding for orientations (FTO) are discussed in this paper. We propose avariable thresholding for orientations (VTO) based on average recent angular velocity. The mainadvantage of the proposed VTO is the ability of balancing the number of state update messages andshift frequency of direction and speed of rotation.