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Guidance of Fixed-Wing UAVs
Published in Rafael T. Yanushevsky, Modern Missile Guidance, 2019
One of the possible applications of the considered rendezvous problem is the so-called aerial refueling, the process of transferring during flight fuel from one aerial vehicle (commonly called the tanker) to another (the receiver). Aerial refueling capability is a critical component of the U.S. military’s ability to operate military aerial vehicles (e.g., bombers, fighters, or surveillance aircraft) in theater with maximum effectiveness, to deploy quickly to distant theaters of operation, and to remain in the air longer while operating in those theaters.
Investigation of Pilot Inceptor Workload and Workload Buildup Technique Through Simulator and In-Flight Studies
Published in The International Journal of Aerospace Psychology, 2022
MIL-STD-1797B(2006) separates flight phases of a piloted aircraft into three categories: Category A, B, and C. Category A includes those nonterminal flight phases that require rapid maneuvering, precision tracking, or precise flight-path control. Examples include air–air combat, ground attack, aerial refueling, close formation, and so on. Pilot gain, which refers to the pilots’ mental state, is of concern in high-performance aircraft. Pilot control inceptor inputs in high gain conditions are likely to expose the lurking defects in a flight control system, which could result in aircraft entering into an out-of-phase condition of control input and response, knows as pilot involved oscillations (PIOs). Pilot gain is expected to be elevated; in other words, high pilot gain control inceptor inputs are expected while performing Category A flight phase tasks, which could lead to potentially dangerous conditions of aircraft entering PIOs and most likely in closer to ground flight conditions, as a pilot perceives the ground as a boundary. The in-flight tests undertaken in T-38 aircraft at USAF TPS (Heritsch et al., 2006; Warren, 2006) provided preliminary inferences about the tendency of increase in pilot gain by imposing boundaries on a point tracking task. In this in-flight study, the in-flight test design and data analysis were primarily focused toward understanding of pilot control inceptor inputs in the Category A flight phase involving ground as a boundary.
LMI-based robust adaptive neural network control for Euler–Bernoulli beam with uncertain parameters and disturbances
Published in International Journal of Control, 2022
Xueyan Xing, Hongjun Yang, Jinkun Liu, Shuquan Wang
It is noteworthy that almost all systems are affected by disturbances due to the environmental changes in the actual application. Besides, the parameter uncertainty is also a universal phenomenon existing in engineering practice. Driven by practical needs, the rigorous handling of disturbances and parameter uncertainties in control design has received an increasing amount of attention. In Dietz and Scherer (2010), a robust disturbance rejection strategy is presented for a particularly structured plant by using the LMI technology. In Filipescu et al. (2003), an adaptive gain smooth sliding control is considered for nonlinear affine systems to cope with uncertain parameters and state functions. Estimators of both uncertainty and disturbance are adopted in the control design of flapping wing aerial vehicle in Yin et al. (2020) and underwater biomimetic vehicle-manipulator in Cai et al. (2019), respectively. In Liu et al. (2020), a spatial aerial refueling hose is considered and, meanwhile, a control method is presented to stabilise the hose with bounded actuators and disturbance rejection.
Detecting visually salient scene areas and deriving their relative spatial relations from continuous street-view panoramas
Published in International Journal of Digital Earth, 2020
Fangli Guan, Zhixiang Fang, Tao Yu, Mingxiang Feng, Fan Yang
The concept of relative spatial relation is useful for achieving accurate relative positioning (Vinny, George, and Mathew 2016), tracking the relative position of aircraft and satellites (Whittaker, Linares, and Crassidis 2013), and guiding pedestrians, vehicles, and spacecraft (Zhang, Vela, et al. 2014). It is also useful for detecting the abnormal state of moving objects (Feng et al. 2019), as well as for matching and registering point clouds (Peng et al. 2014). In space missions, the relative spatial relation is used for relative positioning and attitude estimation in the final phase of autonomous docking (Philip and Ananthasayanam 2003), aerial refueling, and spatial relative navigation (Williamson et al. 2009). In UAV aerial operation, relative spatial relation allows for precise UAV cooperative flight with relative positioning information without the use of GPS technology (Qu, Wu, and Zhang 2013), and enables autonomous guiding and landing (Yang and Wang 2013). In the field of driverless cars and navigation, the relative position and other relative information can assess the safety of autonomous driving (Pollard et al. 2013) and assist with dynamic obstacle avoidance (Uradzinski, Liu, and Jiang 2010). Additionally, relative spatial relation can be applied to AR navigation applications (Kaneto and Komuro 2016).