The Experts below are selected from a list of 45 Experts worldwide ranked by ideXlab platform
Adam Dershowitz - One of the best experts on this subject based on the ideXlab platform.
-
International Space Station Leak Localization Using Attitude Response Data
Journal of Guidance Control and Dynamics, 2006Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the international space station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time unscented filter with a dynamical model, including external disturbances such as aerodynamic drag and gravity gradient. The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that the leak is caused by only one hole. Knowledge of the vent thrust magnitude and its resulting disturbance torque is needed to estimate the moment arm. The vent thrust direction is assumed to be perpendicular to the structure surface, and its magnitude is determined using an extended Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response,buttheactualgeometricstructureofthespacestationeliminatesmanyofthepossiblesolutions.Numerical results show that the leak localization method is very efficient when used with the conventional sequential hatch closure or airflow induction sensor system.
-
INTERNATIONAL SPACE STATION LEAK LOCALIZATION USING VENT TORQUE ESTIMATION
2004Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:A new method is presented in this paper to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using an unscented fi lter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible solutions. Numerical results show that the leak localization method is very efficient wh en used with the conventional sequential hatch closure or airfl ow induction sensor system. A user friendly computer code has been developed to find the leak location with the proposed met hod.
-
ISS LEAK LOCALIZATION USING ATTITUDE RESPONSE
AIAA Guidance Navigation and Control Conference and Exhibit, 2001Co-Authors: Jong-woo Kirn, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time predictive filter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible
John L. Crassidis - One of the best experts on this subject based on the ideXlab platform.
-
International Space Station Leak Localization Using Attitude Response Data
Journal of Guidance Control and Dynamics, 2006Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the international space station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time unscented filter with a dynamical model, including external disturbances such as aerodynamic drag and gravity gradient. The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that the leak is caused by only one hole. Knowledge of the vent thrust magnitude and its resulting disturbance torque is needed to estimate the moment arm. The vent thrust direction is assumed to be perpendicular to the structure surface, and its magnitude is determined using an extended Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response,buttheactualgeometricstructureofthespacestationeliminatesmanyofthepossiblesolutions.Numerical results show that the leak localization method is very efficient when used with the conventional sequential hatch closure or airflow induction sensor system.
-
INTERNATIONAL SPACE STATION LEAK LOCALIZATION USING VENT TORQUE ESTIMATION
2004Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:A new method is presented in this paper to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using an unscented fi lter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible solutions. Numerical results show that the leak localization method is very efficient wh en used with the conventional sequential hatch closure or airfl ow induction sensor system. A user friendly computer code has been developed to find the leak location with the proposed met hod.
-
ISS LEAK LOCALIZATION USING ATTITUDE RESPONSE
AIAA Guidance Navigation and Control Conference and Exhibit, 2001Co-Authors: Jong-woo Kirn, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time predictive filter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible
Srinivas R. Vadali - One of the best experts on this subject based on the ideXlab platform.
-
International Space Station Leak Localization Using Attitude Response Data
Journal of Guidance Control and Dynamics, 2006Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the international space station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time unscented filter with a dynamical model, including external disturbances such as aerodynamic drag and gravity gradient. The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that the leak is caused by only one hole. Knowledge of the vent thrust magnitude and its resulting disturbance torque is needed to estimate the moment arm. The vent thrust direction is assumed to be perpendicular to the structure surface, and its magnitude is determined using an extended Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response,buttheactualgeometricstructureofthespacestationeliminatesmanyofthepossiblesolutions.Numerical results show that the leak localization method is very efficient when used with the conventional sequential hatch closure or airflow induction sensor system.
-
INTERNATIONAL SPACE STATION LEAK LOCALIZATION USING VENT TORQUE ESTIMATION
2004Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:A new method is presented in this paper to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using an unscented fi lter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible solutions. Numerical results show that the leak localization method is very efficient wh en used with the conventional sequential hatch closure or airfl ow induction sensor system. A user friendly computer code has been developed to find the leak location with the proposed met hod.
-
ISS LEAK LOCALIZATION USING ATTITUDE RESPONSE
AIAA Guidance Navigation and Control Conference and Exhibit, 2001Co-Authors: Jong-woo Kirn, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time predictive filter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible
Jong-woo Kim - One of the best experts on this subject based on the ideXlab platform.
-
International Space Station Leak Localization Using Attitude Response Data
Journal of Guidance Control and Dynamics, 2006Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:This paper presents a new method to localize air leaks on the international space station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using a real-time unscented filter with a dynamical model, including external disturbances such as aerodynamic drag and gravity gradient. The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that the leak is caused by only one hole. Knowledge of the vent thrust magnitude and its resulting disturbance torque is needed to estimate the moment arm. The vent thrust direction is assumed to be perpendicular to the structure surface, and its magnitude is determined using an extended Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response,buttheactualgeometricstructureofthespacestationeliminatesmanyofthepossiblesolutions.Numerical results show that the leak localization method is very efficient when used with the conventional sequential hatch closure or airflow induction sensor system.
-
INTERNATIONAL SPACE STATION LEAK LOCALIZATION USING VENT TORQUE ESTIMATION
2004Co-Authors: Jong-woo Kim, John L. Crassidis, Srinivas R. Vadali, Adam DershowitzAbstract:A new method is presented in this paper to localize air leaks on the International Space Station based on the spacecraft attitude and rate behavior produced by a mass Expulsion Force of the leaking air. Thrust arising from the leak generates a disturbance torque, which is estimated using an unscented fi lter with a dynamical model (including external disturbances such as aerodynamic drag and gravity-gradient). The leak location can be found by estimating the moment arm of the estimated disturbance torque, assuming that leak is caused by only one hole. Knowledge of the leak thrust magnitude and its resulting disturbance torque are needed to estimate the moment arm. The leak thrust direction is assumed to be perpendicular to the structure surface and its magnitude is determined using a Kalman filter with a nozzle dynamics model. There may be multiple leak locations for a given response, but the actual geometric structure of the space station eliminates many of the possible solutions. Numerical results show that the leak localization method is very efficient wh en used with the conventional sequential hatch closure or airfl ow induction sensor system. A user friendly computer code has been developed to find the leak location with the proposed met hod.
Boris V. Somov - One of the best experts on this subject based on the ideXlab platform.
-
Aspects of the Global MHD Equilibria and Filament Eruptions in the Solar Corona
Space Science Reviews, 2001Co-Authors: Yuri E. Litvinenko, Boris V. SomovAbstract:This is a review of several promising approaches for analyzing the accumulation and release of magnetic energy in filament eruptions and coronal mass ejections in the solar corona. The importance of the magnetic virial theorem for understanding the role of slowly changing boundary conditions in the photosphere is stressed. A possible role of the magnetic Expulsion Force in the solar filament dynamics is also discussed.
