In this paper, a chattering-free sliding-mode control is mainly proposed in a second-order discrete-time system. For achieving this purpose, firstly, a suitable control law would be derived by using the discrete-time Lyapunov stability theory and the sliding-mode concept. Then the input constraint is taken into account as a saturation function in the proposed control law. In order to guarantee ...

This paper deals with the control of lighter-than-air vehicles, more specifically the design of an integrated guidance, navigation and control (GNC) scheme that is capable of navigating an airship through a series of constant-altitude, planar waypoints. Two guidance schemes are introduced, a track-specific guidance law and a proportional navigation guidance law, that provide the required signal...

To perform formation flight of multiple UAVs (Unmanned Aerial Vehicles), an accurate guidance law is required. Existing guidance law based on nonlinear path-following guidance method provides outstanding path following performance. However, the nonlinear guidance law does not reflect the characteristics of UAV, and therefore the performance of the guidance law may be degraded in the real enviro...

In order to intercept hypersonic vehicles in near-space, a head-pursuit cooperative guidance law is proposed this paper. Firstly, interceptors are regarded as multi-agents, and the communication relationship between them represented by graph theory. Based on time consistency theory of multi-agent system sliding mode theory, designed along line-of-sight (LOS) ensure cooperation interceptors. Sec...

An integrated fuzzy guidance (IFG) law for a surface to air homing missile is introduced. The introduced approach is a modification of the well-known proportional navigation guidance (PNG) law. The IFG law enables the missile to approach a high maneuvering target while trying to minimize control effort as well as miss-distance in a two-stage flight. In the first stage, while the missile is far ...

Homing preset and adaptive experiments with Finite State Machines (FSMs) are widely used when a non-initialized discrete event system is given for testing and thus, has to be set to the known state at the first step. The length of a shortest homing sequence is known to be exponential with respect to the number of states for a complete observable nondeterministic FSM while the problem of checkin...

This paper proposes a modified nonsingular fast terminal sliding mode (NFTSM) guidance law to solve the problem of ground moving target tracking for fixed-wing unmanned aerial vehicle (UAV) in a planar environment. Firstly, the loitering algorithm is analysed, which can steer the UAV to follow and circle around a ground moving target with the desired distance by heading angle control. Secondly,...

In this article, a more generalized form of the impact time and angle control guidance law is proposed based on the linear quadratic optimal control methodology. For the purpose on controlling an additional constraint such as the impact time, we introduce an additional state variable that is defined to be the jerk (acceleration rate). Additionally, in order to provide an additional degree of fr...

This paper presents an impact-angle guidance law of unmanned aerial vehicles (UAVs) with time-varying thrust in a boosting phase. Most current research on assumes that UAV speed is constant terms controlled thrust. However, the and acceleration phase keep changing because Environmental factors manufacturing process error may prohibit accurately predicting vehicle-thrust profiles. We propose non...

To improve applicability and adaptability of the impact time control guidance (ITCG) in practical engineering, a two-stage ITCG law with simple but effective structure is proposed based on hybrid proportional navigation, namely, pure-proportional-navigation retro-proportional-navigation. For case error less than zero, first stage guided trajectory driven by retro-proportional-navigation second ...