A model of autonomous positioning through associating environment memory information is presented for unmanned combat aerial vehicle(UCAV).The representation strategy of environment by constructing place cells is used...A model of autonomous positioning through associating environment memory information is presented for unmanned combat aerial vehicle(UCAV).The representation strategy of environment by constructing place cells is used to produce the memory information,and the landmarks in memory are retrieved through perceiving and processing the environment.During UCAV′s flight,the landmarks are obtained in real-time and are matched with the landmarks in memory.Then,the idea of ranging positioning is adopted to calculate UCAV′s location based on the corresponding relationship between current obtained landmarks and the memorized landmarks.Simulation shows that the proposed model can realize autonomous positioning in the memorized environment,and the positioning performance is well when the sensor has a high precision.展开更多
Pedestrian inertial positioning is an effective means when satellites fail. Heading accuracy determines the performance of pedestrian inertial positioning. To realize an accurate positioning, a heading drift correctio...Pedestrian inertial positioning is an effective means when satellites fail. Heading accuracy determines the performance of pedestrian inertial positioning. To realize an accurate positioning, a heading drift correction method was proposed. An in-situ active rotation is performed before autonomous positioning, and the error compensation coefficient of biaxial geomagnetic measurement is obtained by using the ellipse fitting correction method to achieve effective suppression of external environmental geomagnetic interference. The corrected biaxial geomagnetic measurement information is used to directly calculate the heading information and combine it with the peak stride detection method and linear step estimation model to achieve autonomous positioning of pedestrians. To verify the effectiveness and stability of the algorithm, several sets of experiments on the autonomous positioning of pedestrians are carried out in an outdoor environment. The experimental results show that the average deviation between the starting point and the endpoint of the proposed algorithm’s positioning trajectory accounts for 0.95% of the total travel in the 150 m positioning experiments.展开更多
Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar ...Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference System according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.展开更多
Vehicle navigation systems are one of the essential tools for automotive intelligence development,playing a crucial role in the process.This study discusses the components,operation principles,classification,and lates...Vehicle navigation systems are one of the essential tools for automotive intelligence development,playing a crucial role in the process.This study discusses the components,operation principles,classification,and latest technological advances of Vehicle navigation systems,aiming to reveal the current state of the latest technological applications of the system in the automotive industry.The study indicates that the core value of vehicle navigation systems lies in precise positioning,enhanced driving safety,intelligent route planning,and other aspects.At present,the market of vehicle navigation systems is witnessing steady growth and faces intense competition from mobile phone navigation.To hold the upper hand in the competition,the industry should utilize policy support from the government,facing up to challenges and seeking solutions to current problems.In the future,the vehicle navigation system should deeply integrate with artificial intelligence(AD),providing diverse,tailored navigation services for customers.These services should cover driving skills,driving habits,etc.Meanwhile,through constant technological innovation,user experience optimization,and the application of deep leaming,the vehicle navigation system is expected to achieve more efficient human-machine interaction and enhanced driving safety and comfortability,thereby improving its competitiveness in the market and tuning it into an indispensable intelligent companion for drivers.展开更多
基金supported by the National Natural Science Foundation of China(No.61273048)
文摘A model of autonomous positioning through associating environment memory information is presented for unmanned combat aerial vehicle(UCAV).The representation strategy of environment by constructing place cells is used to produce the memory information,and the landmarks in memory are retrieved through perceiving and processing the environment.During UCAV′s flight,the landmarks are obtained in real-time and are matched with the landmarks in memory.Then,the idea of ranging positioning is adopted to calculate UCAV′s location based on the corresponding relationship between current obtained landmarks and the memorized landmarks.Simulation shows that the proposed model can realize autonomous positioning in the memorized environment,and the positioning performance is well when the sensor has a high precision.
文摘Pedestrian inertial positioning is an effective means when satellites fail. Heading accuracy determines the performance of pedestrian inertial positioning. To realize an accurate positioning, a heading drift correction method was proposed. An in-situ active rotation is performed before autonomous positioning, and the error compensation coefficient of biaxial geomagnetic measurement is obtained by using the ellipse fitting correction method to achieve effective suppression of external environmental geomagnetic interference. The corrected biaxial geomagnetic measurement information is used to directly calculate the heading information and combine it with the peak stride detection method and linear step estimation model to achieve autonomous positioning of pedestrians. To verify the effectiveness and stability of the algorithm, several sets of experiments on the autonomous positioning of pedestrians are carried out in an outdoor environment. The experimental results show that the average deviation between the starting point and the endpoint of the proposed algorithm’s positioning trajectory accounts for 0.95% of the total travel in the 150 m positioning experiments.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10973030,10973032,11003039,10903032 and 10973049)the National Science Foundation of Shanghai,China (Grant No. 10ZR1435700)
文摘Prior to achieving high precision navigation of a spacecraft using X-ray observations, a pulsar rotation model must be built and analysis of the precise posi- tion of the Earth should be performed using ground pulsar timing observations. We can simulate time-of-arrival ground observation data close to actual observed values before using pulsar timing observation data. Considering the correlation between the Earth＇s position and its short arc section of an orbit, we use polynomial regression to build the correlation. Regression coefficients can be calculated using the least square method, and a coordinate component series can also be obtained; that is, we can calcu- late Earth＇s position in the Barycentric Celestial Reference System according to pulse arrival time data and a precise pulsar rotation model. In order to set appropriate param- eters before the actual timing observations for Earth positioning, we can calculate the influence of the spatial distribution of pulsars on errors in the positioning result and the influence of error source variation on positioning by simulation. It is significant that the threshold values of the observation and systematic errors can be established before an actual observation occurs; namely, we can determine the observation mode with small errors and reject the observed data with big errors, thus improving the positioning result.
文摘Vehicle navigation systems are one of the essential tools for automotive intelligence development,playing a crucial role in the process.This study discusses the components,operation principles,classification,and latest technological advances of Vehicle navigation systems,aiming to reveal the current state of the latest technological applications of the system in the automotive industry.The study indicates that the core value of vehicle navigation systems lies in precise positioning,enhanced driving safety,intelligent route planning,and other aspects.At present,the market of vehicle navigation systems is witnessing steady growth and faces intense competition from mobile phone navigation.To hold the upper hand in the competition,the industry should utilize policy support from the government,facing up to challenges and seeking solutions to current problems.In the future,the vehicle navigation system should deeply integrate with artificial intelligence(AD),providing diverse,tailored navigation services for customers.These services should cover driving skills,driving habits,etc.Meanwhile,through constant technological innovation,user experience optimization,and the application of deep leaming,the vehicle navigation system is expected to achieve more efficient human-machine interaction and enhanced driving safety and comfortability,thereby improving its competitiveness in the market and tuning it into an indispensable intelligent companion for drivers.
