Guidance Problem Research Articles

Three-dimensional trajectory tracking guidance against near-space maneuvering targets with multiple constraints under wind field

This paper presents a three-dimensional disturbance observer-based adaptive tracking guidance scheme for the trajectory tracking problem of a missile intercepting a hypersonic vehicle with the wind field, autopilot lag dynamics, and input saturation. Unlike most of the existing missile trajectory tracking guidance systems without velocity controllability and external wind field model, the wind field model is added to the dynamic model, and the velocity control channel is introduced into the three-dimensional trajectory tracking guidance problem to prevent impractical scenarios and increase tracking precision. The proposed tracking guidance methodology incorporates the sliding mode and adaptive control techniques, in which the sliding mode motion is finite time stable independently of the tracking guidance system's initial conditions. Also, the super twisting switch control law is added to cope with the chattering problem. In this context, external uncertainty disturbances and unmeasured states are lumped into lump disturbance and estimated using the backpropagation neural network extended state observer. To this end, numerical simulations demonstrate the tracking to reach zero between 3 s and 5 s against various uncertainties in engineering practical, and position tracking errors are within 0.15 m, superior to the existing tracking guidance methods.

Multi-Constrained Geometric Guidance Law with a Data-Driven Method

A data-driven geometric guidance method is proposed for the multi-constrained guidance problem of variable-velocity unmanned aerial vehicles (UAVs). Firstly, a two-phase flight trajectory based on a log-aesthetic space curve (LASC) is designed. The impact angle is satisfied by a specified straight-line segment. The impact time is controlled by adjusting the phase switching point. Secondly, a deep neural network is trained offline to establish the mapping relationship between the initial conditions and desired trajectory parameters. Based on this mapping network, the desired flight trajectory can be generated rapidly and precisely. Finally, the pure pursuit and line-of-sight (PLOS) algorithm is employed to generate guidance commands. The numerical simulation results validate the effectiveness and superiority of the proposed method in terms of impact time and angle control under time-varying velocity.

Integrated robust navigation and guidance for the kinetic impact of near-earth asteroids based on deep reinforcement learning

The defense against near-Earth asteroids (NEAs) using kinetic impact is faced with various challenges, including limited maneuverability of the impactor, inaccurate dynamic models, poor observability of relative navigation, and control execution errors. To address these challenges, an integrated robust navigation and guidance method for the kinetic impact of NEAs based on deep reinforcement learning (DRL) is proposed in this paper, which can directly map angle measurements by a monocular camera to guidance maneuvers. Firstly, a discrete partial observable Markov decision process (POMDP) is modeled for the integrated navigation and guidance problem of NEA interception. To address the situation where impactors are usually only equipped with aiming cameras and only the line of sight (LOS) angle is measured, past and current LOS measurements are concatenated into a one-dimensional state observation vector to directly introduce the memory of historical state information. A shaping reward function design based on potential energy has also been proposed to solve the problem of sparse reward as the main goal. Subsequently, proximal policy optimization (PPO) is used to solve the established POMDP model, obtaining an integrated navigation and guidance policy that directly maps from the original output of the navigation sensor to the guidance command. The potentially hazard asteroid (PHA) Bennu is used as the target and a typical kinetic impact defense scenario is designed to simulate and verify the model and method proposed in this paper, considering the influence of multiple factors. Numerical simulation results show that the proposed method achieves an interception accuracy of 203.58 m (mean value). The proposed method abandons the traditional separate design of navigation and guidance algorithms, and its robustness has been tested and verified in a wide range of uncertain environments.

GAMBARAN PERILAKU ALTRUISME GURU BIMBINGAN DAN KONSELING SMP DI KABUPATEN PASURUAN

The purpose of this study was to find out the description of the altruistic behavior of the junior high school guidance and counseling teachers in Pasuruan Regency which is based on the existence of altruistic behavior problems of the junior high school guidance and counseling teachers in Pasuruan Regency. This research is a quantitative research with a descriptive design, to provide an overview of a symptom or phenomenon regarding the altruistic behavior of counseling teachers. The sampling technique in this study used the Issac & Michael table at an error rate of 5% of the Counseling Teacher population with a sample of 105 teachers from a total population of 146 teachers. Data analysis to test the assumptions in this study used the Pearson product moment correlation with the help of the JASP program version 0.16 for windows. The results in this study showed that 80% of the altruistic behavior of counseling guidance teachers was classified as moderate and 20% was classified as low and the aspect that dominated their altruistic behavior was the Helper.

Cooperative Guidance Strategy for Active Spacecraft Protection from a Homing Interceptor via Deep Reinforcement Learning

The cooperative active defense guidance problem for a spacecraft with active defense is investigated in this paper. An engagement between a spacecraft, an active defense vehicle, and an interceptor is considered, where the target spacecraft with active defense will attempt to evade the interceptor. Prior knowledge uncertainty and observation noise are taken into account simultaneously, which are vital for traditional guidance strategies such as the differential-game-based guidance method. In this set, we propose an intelligent cooperative active defense (ICAAI) guidance strategy based on deep reinforcement learning. ICAAI effectively coordinates defender and target maneuvers to achieve successful evasion with less prior knowledge and observational noise. Furthermore, we introduce an efficient and stable convergence (ESC) training approach employing reward shaping and curriculum learning to tackle the sparse reward problem in ICAAI training. Numerical experiments are included to demonstrate ICAAI’s real-time performance, convergence, adaptiveness, and robustness through the learning process and Monte Carlo simulations. The learning process showcases improved convergence efficiency with ESC, while simulation results illustrate ICAAI’s enhanced robustness and adaptiveness compared to optimal guidance laws.

Guidance, navigation and attitude control of mini-satellites in a low earth orbit constellation for areal survey

The problems of guidance, navigation and attitude control in a constellation of mini-observation satellites are considered. The developed methods and algorithms for scanning areal survey performed by these constellations in the low sun-synchronous orbits are presented. The most important new results are methods for coordinated angular guidance of satellites in the constellation’s orbital planes and the comparison results for sequences of the areal space surveys.

Adaptive cooperative guidance with seeker-less followers: A position coordination-based framework

This paper addresses the problem of cooperative guidance for multiple flight vehicles, comprising a leader and seeker-less followers. All the flight vehicles are required to hit the target simultaneously at a desired impact time, even though the target information is unavailable to the followers. To achieve this, a fixed-time convergent guidance law is proposed for the leader, incorporating impact time control. We introduce an adaptive cooperative guidance strategy for the seeker-less followers through coordinated position location relative to the leader. The simulation results validate the effectiveness satisfactorily coinciding with the theoretical analysis.

Employment of the Disabled as a Mechanism for the Development of the Agrosphere and Rural Territories

The article reveals the problems of vocational guidance and employment of people with disabilities living in rural areas. Potential opportunities for expanding the labor participation of disabled people in the agro-industrial sector and other sectors of the rural economy are considered. The role of education in stimulating the labor activity of disabled people is revealed. The issues of organizing retraining and advanced training of disabled people living in rural areas are considered. Arguments are given that the involvement of people with disabilities in labor activity is one of the mechanisms for the development of the agrosphere and rural areas. The authors conclude that in order to perform the career guidance function, organizations of additional vocational education need to interact with employment service bodies, executive bodies of state authority of the constituent entities of the Russian Federation, local self-government bodies, bodies of territorial public self-government, industry associations operating in rural areas. The measures mentioned in the article, according to the authors, will stimulate the economic activity of disabled people; promote vocational education for disabled people and their employment, create conditions for the development of new forms of staff training and retraining in the countryside, support traditional types of agricultural activities and businesses, accelerate the introduction of new activities and contribute to the stable integrated development of rural areas.

Distributed adaptive cooperative guidance against maneuvering targets with time-varying terminal angle constraint and overload saturation

Distributed adaptive cooperative guidance problem for multiple missiles intercepting a maneuvering target with time-varying terminal angle constraint and overload saturation is investigated in this paper. First of all, an extended state observer (ESO) is designed for each missile which can estimate the line-of-sight (LOS) rate and unknown external disturbances simultaneously. Secondly, a sliding manifold is proposed for each missile which consists of states of the ESO and neighbor terminal angle formation error. Then, a distributed cooperative guidance law is presented which can achieve the terminal angle constrained cooperative guidance. Furthermore, in order to deal with overload saturation, an auxiliary state is designed for the stability of the whole guidance system. Thirdly, the design process of cooperative guidance law is summarized as a guidance algorithm and the stability of the guidance error dynamics is proved via Lyapunov theories. Finally, the validity of the presented cooperative guidance algorithm is demonstrated by a numerical example.

Cooperative game penetration guidance for multiple hypersonic vehicles under safety critical framework

The rapid development of the anti-missile weapon technology brings new challenges to the cooperative penetration strategy solution and the guidance law design for Hypersonic Vehicles (HVs). This paper studies the coordinated game penetration guidance problem for multiple hypersonic vehicles faced with space threat areas. A scheme for seeking cooperative game penetration guidance strategy under safety critical control framework is presented. In this scheme, a multi-HV cooperative game model is proposed in a minimum optimization form which can simplify the solving process and accelerate the computing speed. Then, a second-order control barrier function is developed to transform the implicit nonlinear constraints of the proposed model into linear ones. In order to obtain better performance of guidance strategy, a composite guidance law under the safety critical control framework is presented to allocate guidance strategies appropriately in the whole process. It is shown that the proposed scheme can guarantee successful penetration while avoiding threat areas. Finally, a comparative simulation with a two-on-three game is conducted to verify the effectiveness of the proposed method.

Multi-Objective Deep Reinforcement Learning for Crowd Route Guidance Optimization

In this study, we propose an improved version of Pareto deep Q-network (PDQN), a multi-objective deep reinforcement learning method, and attempt to demonstrate its effectiveness in a real-world problem such as crowd route guidance strategy optimization. Overcrowding during crowd movement can sometimes lead to accidents; therefore, it is imperative to guide crowds to move safely and efficiently. Safety and efficiency are conflicting objectives, and how to dynamically determine guidance can be formulated as a multi-objective sequential decision-making problem. PDQN is suitable for solving these problems, but its applicability to complex real-world problems has not been fully verified. To apply PDQN to real problems, we propose to adjust the parameters of PDQN and improve the action selection criteria during learning. A toy problem and a crowd guidance problem using multi-agent crowd simulation are adopted to evaluate the performance of improved PDQN. Experimental results show that the improved PDQN can search for good strategies compared with the original PDQN and can obtain better strategies than simplified strategies.

Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer

This paper investigates interception missiles’ trajectory tracking guidance problem under wind field and external disturbances in the boost phase. Indeed, the velocity control in such trajectory tracking guidance systems of missiles is challenging. As our contribution, the velocity control channel is designed to deal with the intractable velocity problem and improve tracking accuracy. The global prescribed performance function, which guarantees the tracking error within the set range and the global convergence of the tracking guidance system, is first proposed based on the traditional PPF. Then, a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid singularities. Meanwhile, an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem. A back propagation neural network (BPNN) extended state observer (BPNNESO) is employed in the inner loop to identify disturbances. The obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors, convergence times, and overshoots.

Analytical reentry guidance framework based on swarm intelligence optimization and altitude-energy profile

Aimed at improving the real-time performance of guidance instruction generation, an analytical hypersonic reentry guidance framework is presented. The key steps of the novel guidance framework are the parameterization of reentry guidance problems and the optimization of parameters. First, a quintic polynomial function of energy was designed to describe the altitude profile. Then, according to the altitude-energy profile, the altitude, velocity, flight path angle, and bank angle were obtained analytically, which naturally met the terminal constraints. In addition, the angle of the attack profile was determined using the velocity parameter. The swarm intelligent optimization algorithms were used to optimize the parameters. The path constraints were enforced by the penalty function method. Finally, extensive simulations were carried out in both nominal and dispersed cases, and the simulation results showed that the proposed guidance framework was effective, high-precision, and robust in different scenarios.

Robust Leader–Follower Cooperative Guidance Under False-Data Injection Attacks

This paper investigates the problem of leader-follower cooperative guidance in consideration of false-data injection attacks (FDIAs). Both the leader and the followers are required to reach the target at a desired impact time, while only the leader can receive the impact time command. A fixed-time convergent guidance law is presented for the leader to hit the target with impact time control. A distributed observer is introduced for each follower to estimate the leader's time to go. The confidence factors and the trust factors are exploited in the distributed observer to cope with FDIAs. Governed by the proposed distributed observer-based cooperative guidance law, the leader and the followers can achieve the simultaneous arrival in the presence of FDIAs. To facilitate the seekers detecting the target, the field-of-view angles of all the flight vehicles can be limited in a permissible range. Numerical simulation is carried out to verify the effectiveness.

PSYCHOLOGICAL ASPECTS OF EARLY CAREER GUIDANCE OF STUDENTS WITH DIFFERENT STARTING OPPORTUNITIES

The article deals with the problem of early career guidance of children, starting from high school age. Based on the analysis of psychological and pedagogical ideas of domestic and foreign psychology scientists and teachers (K. D. Ushinsky, B. G. Ananyev, A. S. Mukhina, V. V. Davydov, G. Johnson, F. Froebel, M. Montessori, etc.), the author proposes an approach to the organisation of an early career guidance system aimed not only at children attending preschool educational institutions and basic secondary schools, but also children with disabilities. The author describes the experience of organising the “Skills of the Young” KidS ® Championship as an important psychodidactic tool attracting various subjects of education to career guidance work.

Robust depletion shutdown guidance algorithm for long-range vehicles with a solid divert control system in large deviation conditions

To address the problem of depletion shutdown precise guidance for a long-range vehicle in large deviation condition, an online guidance algorithm based on Bezier curves and zero-range orientation (ZRO) is proposed under the conditions of thrust magnitude deviation, thrust direction deviation, mass flow rate deviation, and depletion shutdown time deviation of the solid divert control system. First, the mapping relationship between the apparent velocity to be gained (AVTG) and the impact deviation is analyzed based on the variational principle. The AVTG is solved with the Newton iterative method in the designed AVTG solution plane. Then, in the plane spanned by the AVTG and the ZRO, the key parameters of the Bezier curve are solved to obtain the Bezier energy management curve by taking the apparent acceleration direction and the angular velocity of the energy management terminal as the ZRO and zero, respectively, as constraints, which effectively reduces the influence of the solid divert control system performance parameter perturbation. Finally, the feedback linearization method is applied to track the Bezier energy management curve. A detailed simulation experiment is designed to analyze the advantages and computational complexity of the proposed algorithm. The Monte Carlo simulation results show that the proposed algorithm has high precision and good robustness, and the 3σ error of the proposed algorithm is 2.58 m. On the STM32F407 single-chip microcomputer, the proposed algorithm takes 25.38 ms, which demonstrates good real-time performance and a certain engineering application value.

Optimal spatial-temporal cooperative guidance against a maneuvering target

This paper proposes an optimal three-dimensional (3-D) spatial-temporal cooperative guidance (STCG) law for intercepting a maneuvering target with impact angle and time constraints. The guidance problem is studied to achieve spatial cooperation for multi-directional attack in the normal channel and temporal cooperation for simultaneous interception in the tangential channel, respectively. Firstly, the 3-D optimal impact-angle-control guidance (OIACG) is introduced to formulate spatial interception geometry. Based on this law, the relative trajectory length is analytically derived and an accurate time-to-go predictor is formulated against maneuvering targets. In the tangential channel, an optimal temporal cooperative guidance is proposed by leveraging high-dimensional Schwarz inequality method. The proposed algorithm is believed to outperform the existing nonlinear cooperative guidance laws due to its optimality with specific performance index for minimizing the control expenditure. The convergence properties of the proposed STCG law are provided to facilitate its practical implementation. Comparison simulations and application under the realistic pursuer model and target estimation are performed to demonstrate the effectiveness and robustness of the proposed cooperative method.

Direct–Indirect Hybrid Strategy for Optimal Powered Descent and Landing

A hybrid algorithm to solve optimal control problems is discussed in the present paper and applied to the powered descent guidance (PDG) problem. A reference solution is first obtained via a convex direct solver and is then used as guess for the primal–dual boundary-value problem associated with the initial problem. In this context, a covector mapping theorem is used to map the multipliers of the direct solution to the corresponding discrete costates of the indirect method. Collocation based on hp pseudospectral scheme is employed for the convex direct step, while single shooting is used for the indirect step. A switching-detection technique further equips the shooting. As opposed to the hybrid convex-indirect algorithm, a state-of-the-art purely indirect algorithm is outlined; such approach merges the same single shooting approach with a homotopic continuation. The proposed methods are applied to the pinpoint landing formulation of the PDG, framed in a three-dimensional environment. The results are finally outlined, comparing the proposed hybrid strategy to the purely indirect approach. The outcome highlights the gain in computational times for the hybrid optimization technique over the fully homotopic scheme, demonstrating the validity of the former for landing trajectory optimization purposes.

Constrained control using novel nonlinear mapping for underactuated unmanned surface vehicles with unknown sideslip angle

This paper addresses the problem of guidance and control for underactuated unmanned surface vehicles (USVs) with state constraints and input saturation, in support of enabling an underactuated USV to follow a parameterized curved path in the case of unknown sideslip angle and cross-tracking error constraint. First, a cross-tracking error constraint line-of-sight (LOS) guidance law with sideslip angle compensation is originally designed to guide an underactuated USV to convergence to the desired path within a time-varying cross-tracking error constraint. Second, a novel nonlinear mapping (NM) function is first constructed to map the heading and surge control subsystems with state constraints to unconstrained nonlinear systems, transforming the constrained control problem into the unconstrained control problem. Subsequently, adaptive fuzzy control laws are designed to achieve the control objectives for the USV using the new unconstrained nonlinear systems with unknown disturbance and input saturation. Then, a series of theoretical analyses using input-to-state stability theories are presented to prove the boundness of the tracking errors for the underactuated USV during path following. Finally, numerical results obtained using a physics-based simulation model are shown to reveal the effectiveness of the guidance and control algorithms.

Three-Dimensional Spatial–Temporal Cooperative Guidance Without Active Speed Control

This paper investigates the three-dimensional (3D) spatial–temporal cooperative guidance problem for multiple missiles with time-varying speeds, which is addressed by a progressive design strategy. First, the zero miss distance and desired impact directions are realized by a 3D vector impact angle control guidance (IACG) law whose time-to-go is predicted accurately and efficiently by a numerical algorithm. Then, by introducing an implicit trajectory-to-go function, the time-to-go control mechanism is clearly revealed under missile speed variation. Accordingly, a coordinated biased term is added to the 3D vector IACG law to ensure a simultaneous attack. Finally, considering the seeker’s field-of-view (FOV) limit, the resultant cooperative guidance law is further augmented by another biased term to prevent the lead angle from exceeding its upper bound. Unlike similar existing results, the proposed one can satisfy multiple complex spatial–temporal constraints without active speed control, thereby manifesting great practical significance. Several numerical simulations are provided to show the effectiveness and advantages of the proposed cooperative guidance law.