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Under the coupling effect between guidance system and control system, the performance of traditional guidance and control method is limited. Therefore, integrated guidance and control (IGC) method is proposed to solve the problem. This method is characterized by the guidance loop and control loop which are considered as a whole part in accordance with the information of the relative motion between...
Because of the remarkable non-linearity, large inertia and strong atmospheric disturbances, traditional control methods cannot ensure the trajectory tracking control performance for a parafoil airdrop robot. In this sense, we propose a trajectory tracking control method based on active disturbance rejection control. Then the proposed control method is evaluated by simulation and airdrop experiment...
This contribution demonstrates the practical realizability of a tailored real-time nonlinear model predictive control (MPC) scheme for off-highway diesel engines. Besides controlling the torque and emissions, the MPC accounts for inequality constraints such as the maximum cylinder pressure by means of an augmented Lagrangian formulation. In addition, the heat-up of the exhaust gas aftertreatment system,...
The physical ground simulation of space defense confrontation is under the contractible time and space coordination of real world. The theoretical foundation of simulation is determined by the uniform constrains that ensured the similarities of geometrical and physical quantities mapping in the two spaces. Under the architectures of space vector linear similarity and time uniform elapse, the sufficient...
The high-accuracy trajectory tracking pneumatic position servo system proposed in this paper mainly consists of a cylinder which is controlled by a proportional directional control value. Due to there exist large extent of parametric uncertainties and severe uncertain nonlinearities in the pneumatic system, an adaptive robust control strategy was constructed, which employs on-line recursive least...
In order to improve the attack effect from the top of maneuver target for air-to-ground missile, three-dimensional proportional navigation model with over-gravity compensation is established based on the relative motion equations. Three-dimensional ballistic trajectory of the missile attacking target is simulated based on the guidance and control closed-loop circuit. The effect of the over-gravity...
In this paper, passive source localization of time-difference-of-arrival (TDOA) is investigated using a swarm of UAVs. First, the measurement model with a parameter dependent variance is introduced. The Cramer-Rao low bound(CRLB) is calculated with parameter dependent of the incoming measurements. Then a method for optimizing UAVs trajectories based on CRLB is proposed. The Dryden model is applied...
This is the second part of the paper devoted to the problem of aircraft control during take-off in the presence of windshears. Here, simulation results based on the control procedures described in Part I are presented.
The aim of this work is to provide a control strategy for a class of vehicles that is based on transformation of the velocity vector expressed in the earth-fixed coordinates. The presented trajectory tracking control algorithm can be applied for a class of fully actuated vehicles. To this class belong: underwater vehicles, indoor airships, and hovercrafts that move at low velocity (v < 3 m/s)....
This paper deals with a one-versus-one air combat algorithm that considers the direction of the lift vector of an unmanned combat aerial vehicle(UCAV). The air combat situation discussed in this study assumes that a gun-fight takes place within visual range(WVR), thus the air combat algorithm will perform the maneuver to chase the enemy's tail. The air combat algorithm previously proposed by the authors...
A modern class of small fixed-wing unmanned aerial vehicles are physically capable of performing exceptional aerobatic maneuvers. This paper presents a methodology for including one of the more functional of these maneuvers, the knife-edge, in motion planning. This is achieved by separating the top-level motion planner from the dynamics and control of the knife-edge maneuver. By coupling feedback...
A formation flight controller can be used in a UAS fleet to avoid collision, reduce fuel consumption, or to execute interactions between the UASs, such as autonomous aerial refueling. In this paper, an autonomous formation flight (AFF) controller based on non linear dynamic inversion (NLDI) and a non-colliding path planner are proposed. The proposed NLDI AFF extends a NLDI controller found in literature...
In this paper, the pitch control of a miniature unmanned airship using a sliding ballast is presented. The sliding ballast design has been developed to address the limited altitude maneuverability of lighter-than-air vehicles by allowing for large changes in vehicle pitch and, when combined with forward facing thrusters, rapid changes in altitude. Using the longitudinal position of the ballast as...
The objective of this paper is to demonstrate the application of optimal control for generating dynamically constrained minimal time trajectories in micro unmanned airships. By design, airships are generally underactuated and underpowered limiting their maneuvering capabilities. Using a simplified dynamic model derived with experimentally derived coefficients, two trajectory planning simulations are...
This paper deals with the Terminal Control Area Aircraft Scheduling Problem and the Aircraft Trajectory Optimization Problem for landing operations in a busy terminal control area. The first problem requires to compute a conflict-free schedule for all aircraft minimizing the overall aircraft delays, while the second deals with the computation of a landing trajectory for each aircraft which minimizes...
On the 19th October 2016, Schiaparelli, the Entry Demonstrator Module (EDM) of the ESA ExoMars Program entered into the martian atmosphere. Although it did not complete a safe landing on Mars, it transmitted data throughout its descent to the surface, until the loss of signal at 1 minute before the expected touch-down on Mars' surface. The main objective of the Atmospheric Mars Entry and Landing Investigations...
Air traffic across the North Atlantic airspace has witnessed an incessant increase over the last decades. However, the efficiency of trans-Atlantic air traffic management is still low nowadays due to the limited radar coverage. Automated Dependent Surveillance-Broadcast systems represents an opportunity to enhance the strategic flight planning over the oceans by reducing separation standards between...
Small unmanned aircraft systems (UAS) typically do not offer the redundancy typical in commercial aviation due to budget and weight limitations. UAS, therefore, have a nontrivial probability of encountering a scenario in-flight that requires an emergency landing. For fixed-wing UAS, one of the most common in-flight emergencies is a total loss of engine or motor thrust, necessitating that the UAS glide...
Unmanned Aerial Vehicle (UAV) development is a field with rising interest in recent years. One of its essential part is the autopilot, responsible for keeping the aircraft in desired flight conditions and for executing navigation tasks. Among the navigation tasks, one that stands out is the path- following operation, which guarantees that the aircraft follows a predefined trajectory. The literature...
This paper deals with monocular image-based aircraft Sense and Avoid for small UAVs. After summarizing previous results of the authors it proposes a complete solution which calculates time to closest point of approach, relative closest point of approach (CPA) and the direction of intruder at CPA. These parameters are enough to make a collision decision and design the avoidance maneuver. The applicability...
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