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Automatic Control for Chase Aircraft
Yamasaki, Takeshi,Enomoto, Keisuke,Tanaka, Daiki,Tanaka, Daiki,Baba, Yoriaki The Korean Society for Aeronautical and Space Scie 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2
Many kinds of unmanned aerial vehicles (UAVs) have been developed for a few decades and some of them are now in operational use. Although each UAV as well as a piloted aircraft might have restrictions to execute some tasks simultaneously or to carry some payloads, one with an automatic chase aircraft might have the potential of multi-capabilities to conduct a variety of missions or to carry more storages. This paper introduces a chase UAV control system to enhance a leader (reference) aircraft capability which has storage restriction. The automatic chase guidance and control system will be introduced with the pure pursuit guidance law combined with relative velocity error corrections, and a dynamic inversion technique in order to generate the guidance forces.
Automatic Control for Chase Aircraft
Takeshi Yamasaki,Keisuke Enomoto,Daiki Tanaka,Hiroyuki Takano,Yoriaki Baba 한국항공우주학회 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2
Many kinds of unmanned aerial vehicles (UAVs) have been developed for a few decades and some of them are now in operational use. Although each UAV as well as a piloted aircraft might have restrictions to execute some tasks simultaneously or to carry some payloads, one with an automatic chase aircraft might have the potential of multi-capabilities to conduct a variety of missions or to carry more storages. This paper introduces a chase UAV control system to enhance a leader (reference) aircraft capability which has storage restriction. The automatic chase guidance and control system will be introduced with the pure pursuit guidance law combined with relative velocity error corrections, and a dynamic inversion technique in order to generate the guidance forces.
Cytoplasmic destruction of p53 by the endoplasmic reticulum-resident ubiquitin ligase ‘Synoviolin’
Yamasaki, Satoshi,Yagishita, Naoko,Sasaki, Takeshi,Nakazawa, Minako,Kato, Yukihiro,Yamadera, Tadayuki,Bae, Eunkyung,Toriyama, Sayumi,Ikeda, Rie,Zhang, Lei,Fujitani, Kazuko,Yoo, Eunkyung,Tsuchimochi, K Wiley (John WileySons) 2007 The EMBO journal Vol.26 No.1
<P>Synoviolin, also called HRD1, is an E3 ubiquitin ligase and is implicated in endoplasmic reticulum -associated degradation. In mammals, Synoviolin plays crucial roles in various physiological and pathological processes, including embryogenesis and the pathogenesis of arthropathy. However, little is known about the molecular mechanisms of Synoviolin in these actions. To clarify these issues, we analyzed the profile of protein expression in synoviolin-null cells. Here, we report that Synoviolin targets tumor suppressor gene p53 for ubiquitination. Synoviolin sequestrated and metabolized p53 in the cytoplasm and negatively regulated its cellular level and biological functions, including transcription, cell cycle regulation and apoptosis. Furthermore, these p53 regulatory functions of Synoviolin were irrelevant to other E3 ubiquitin ligases for p53, such as MDM2, Pirh2 and Cop1, which form autoregulatory feedback loops. Our results provide novel insights into p53 signaling mediated by Synoviolin.</P>
Trajectory Guidance and Control for a Small UAV
Yoichi Sato,Takeshi Yamasaki,Hiroyuki Takano,Yoriaki Baba 한국항공우주학회 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2
The objective of this paper is to present trajectory guidance and control system with a dynamic inversion for a small unmanned aerial vehicle (UAV). The UAV model is expressed by fixed-mass rigid-body six-degree-of-freedom equations of motion, which include the detailed aerodynamic coefficients, the engine model and the actuator models that have lags and limits. A trajectory is generated from the given waypoints using cubic spline functions of a flight distance. The commanded values of an angle of attack, a sideslip angle, a bank angle and a thrust, are calculated from guidance forces to trace the flight trajectory. To adapt various waypoint locations, a proportional navigation is combined with the guidance system. By the decision logic, appropriate guidance law is selected. The flight control system to achieve the commands is designed using a dynamic inversion approach. For a dynamic inversion controller we use the two-timescale assumption that separates the fast dynamics, involving the angular rates of the aircraft, from the slow dynamics, which include angle of attack, sideslip angle, and bank angle. Some numerical simulations are conducted to see the performance of the proposed guidance and control system.
Trajectory Guidance and Control for a Small UAV
Sato, Yoichi,Yamasaki, Takeshi,Takano, Hiroyuki,Baba, Yoriaki The Korean Society for Aeronautical and Space Scie 2006 International Journal of Aeronautical and Space Sc Vol.7 No.2
The objective of this paper is to present trajectory guidance and control system with a dynamic inversion for a small unmanned aerial vehicle (UAV). The UAV model is expressed by fixed-mass rigid-body six-degree-of-freedom equations of motion, which include the detailed aerodynamic coefficients, the engine model and the actuator models that have lags and limits. A trajectory is generated from the given waypoints using cubic spline functions of a flight distance. The commanded values of an angle of attack, a sideslip angle, a bank angle and a thrust, are calculated from guidance forces to trace the flight trajectory. To adapt various waypoint locations, a proportional navigation is combined with the guidance system. By the decision logic, appropriate guidance law is selected. The flight control system to achieve the commands is designed using a dynamic inversion approach. For a dynamic inversion controller we use the two-timescale assumption that separates the fast dynamics, involving the angular rates of the aircraft, from the slow dynamics, which include angle of attack, sideslip angle, and bank angle. Some numerical simulations are conducted to see the performance of the proposed guidance and control system.
Kojima Tsukasa,Yamasaki Yuzo,Kamitani Takeshi,Yabuuchi Hidetake,Shirasaka Takashi,Shimomiya Yamato,Kondo Masatoshi,Hamasaki Hiroshi,Kato Toyoyuki,Nagao Michinobu,Honda Hiroshi 아시아심장혈관영상의학회 2019 Cardiovascular Imaging Asia Vol.3 No.1
Objective: The smallest diagnostically sufficient amount of contrast media (CM) should be used for coronary computed tomography angiography (CCTA) to minimize the risk of contrast- induced nephrotoxicity in elderly patients with coronary artery disease. The purpose of this study was to propose dynamic-CCTA using a low dose of CM and temporal maximum intensity projection (TMIP) and to investigate its image quality compared to standard-CCTA. Materials and Methods: Participants comprised 30 patients with coronary artery disease who underwent dynamic-CCTA and standard-CCTA using 320-row CT. Dynamic-CCTA was continuously performed at mid-diastole throughout 15–25 cardiac cycles after bolus injection of CM [103 mg iodine/kg body weight (mgI/kg)]. TMIP-CCTA was reconstructed from three-phase dynamic-CCTA data, including a phase with peak enhancement of the ascending aorta. Standard-CCTA was performed using a standard CM dose (259 mgI/kg). Image quality of both TMIP-CCTA and standard-CCTA was analyzed. Results: The amount of CM used in TMIP-CCTA and standard-CCTA was 16.2±2.6 mL and 40.1±7.3 mL, respectively. The mean effective radiation dose was not significantly different between the two methods. Mean coronary attenuation was significantly lower for TMIP-CCTA than standard-CCTA [346.9±82.8 Hounsfield units (HU) vs. 455.4±75.3 HU, p<0.05]. Image noise was significantly lower for TMIP-CCTA than standard-CCTA (20.0±3.2 HU vs. 28.1± 3.6 HU, p<0.05). There were no differences in signal-to-noise ratio and visual assessment scores between the two methods. Conclusion: TMIP-CCTA can be performed using more than 50% less CM with the same image quality as standard-CCTA.
Hirotoshi Sakaida,Takeshi Yamasaki,Hiroyuki Takano,Yoriaki Baba 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-
This paper presents an integrated navigation system for a guidance and control system of a small UAV The navigation part consists of GPS/INS navigation suits equipped with various MEMS sensors and a small general purpose GPS receiver, which are low cost and have been achieved the miniaturization. Since a state estimation algorithm for feedback control uses highly nonlinear equations, the Unscented Kalman Filter (UKF) which is one of the most well-known, nonlinear and maximum likelihood estimation methods, is expected to perform as an excellent filter. In this research, the possibility of the system's installment with high accuracy is researched using the UKF. The effectiveness of the integrated navigation system will be performed by several simulations, along with a series of experiments.
Optimal Spacecraft Rendezvous with PNG
Hiroyuki Takano,Mini Matsuda,Takeshi Yamasaki,Isao Yamaguchi 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10
Recently, along with International Space Station, many rendezvous are carried out around the earth. Some of them are unmanned space freights and require automatic rendezvous procedure. In this paper, spacecraft rendezvous with input time-lag system are formulated as nonlinear programming problems based on the proportional navigation guidance (PNG) and numerically analyzed. The optimal solutions were obtained for several objectives. The problem of choice of the navigation constant that provides minimizing rendezvous time and control effort is analyzed. The results of computer simulation are given.
A note on the Trajectory Optimization of a Rigid body aircraft
Osuga Hideyo,Takano Hiroyuki,Yamasaki Takeshi,Baba Yoriaki 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-
Recently, the stability and performance of the aircraft are developed in many aspects, for example, new materials, new structures, wings like the supercritical wings or the winglets, engines like the scram engines or the TVC and many control methods using computers and fly-by-wire technology, etc. Therefore, those aircraft can fly on new trajectories which used to be impossible before. These maneuvers are totally new both for pilots and engineers and should be studied to know how to fly and which abilities are required to carry out such maneuvers very well. In this paper, we formulate the vertical maneuvers of a rigid body aircraft having the post stall maneuverability with the thrust vector control as optimal trajectory problems and analyzed them with the non-linear programming. We chose the night time as the performance index and solve it as a minimum time problem. Furthermore, on the phenomenon that occurred in this analysis, we tried to reduce the number of the variables by removing one control.
Collision Avoidance of the Aircraft in the 3 Dimensional Space
Yoshihiro Yamaguchi,Hiroyuki Takano,Takeshi Yamasaki,Isao Yamaguchi 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10
Recently, domestic and overseas LCC’s (Low Cost Carriers) increase air-traffic in Japan. However, we have narrow domain and many airports. Large training areas of USAF or JSDF also exist in the airspace. In the present circumstances, the flight safety is kept by separating airways from training areas. In the near future, increasing number of flights will make severe situation. In this paper, we try to optimize the evasive courses of aircraft in the narrow airspace. We formulate collision avoidance as a nonlinear programming problem and analyzed numerically. The optimal solution we obtained show courses in narrower spaces than ordinary ones. The assumption of limited airspaces is useful in severe situation like bad weather. Thus, this study might be a good proposal to decide direction for collision avoidance.