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Traditional deadbeat predictive current control is an effective control approach, due to its simple concept, easy implementation, and fast dynamic response. However, the parameter mismatch is one of the main problems affecting its wide application. Model-free predictive current control on the basis of the extended state observer (ESO-MFPCC) is an effective solution to the above problem, while the bandwidth limitation in ESO will reduce the control performance. Moreover, because of the voltage limitation of the power converter, in response to load impacts, the motor potentially has poor dynamic performance under the overmodulation region. In order to solve these above problems, model-free predictive current control on the basis of the adaptive sliding mode observer (ASMO-MFPCC) with an overmodulation scheme is proposed. First, the ASMO-MFPCC can preferably improve system parameter robustness without bandwidth limitation. In addition, the vertical method for optimizing dynamic performance in the overmodulation region is proposed, so that the quicker and better dynamic response is obtained between the linear modulation region and the overmodulation region. Finally, the feasibility and effectiveness of the method, carried on a 1-KW surfaced permanent magnet synchronous motor, are verified through the experimental results.

This paper investigates the characteristic modeling of a novel foldable wing aircraft and evaluates the control performance of various command tracking controllers. Firstly, a longitudinal four-degree-of-freedom nonlinear dynamical model is developed by employing the screw theory in conjunction with the Newton–Euler method. Then, the linear variable parameter (LPV) model is established with flight-path angle and folding angle as time-varying parameters. A trim and small-disturbance linearization is applied to each working point within the flight mission. Eventually, to ensure the flight stability of the deformation process, this paper employs both LQR and PID controllers, accomplishing the command tracking control for the nonlinear model. Simulation results show that compared with the fixed configuration control strategy, adopting a variable configuration control strategy reduces the angle of attack, thereby mitigating the stall risk caused by the excessive angle of attack during the climbing process. Additionally, the propeller speed is diminished under the variable configuration control strategy, which helps to minimize the flight energy consumption and improve the cruise capability.

The flight-structural dynamics of a high-aspect-ratio wing challenge the flight control design. This paper develops a reduced model of coupled dynamics with stability consideration. The structural dynamics are formulated with dihedrals, and the central loads drive the deformation. The control-oriented model with essential coupled dynamics is formulated. Modal sensitivity analysis and input–output pairing are performed to identify the control structure. Besides, an example of flight control design is provided to discuss the necessity of considering structural dynamics in controller design. Analytical coupled flight dynamics provide a system-theoretic approach for stability and facilitate model-based control techniques. Simulation results reveal the characteristics of flight-structural coupled dynamics and demonstrate that the influence of flexible modes should be considered in control design, especially in lateral dynamics.

The identification of ancient wool is of great significance in archaeology; however, conventional methods are unwieldy or even ineffective when testing contaminated or severely degraded ancient samples. Therefore, it is highly desirable to develop an ultrasensitive detection method for ancient wool. In this study, an ultrasensitive electrochemical immunosensor is proposed and developed to detect ancient wool, where graphene oxide (GO), aldehyde-functionalized ionic liquid (AFIL) composites and gold nanoparticles (AuNPs) are synthesized as efficient signal amplifiers. With their large surface area and excellent electron transfer efficiency, the combination of GO-AFIL and AuNPs endows the immunosensor with excellent electrochemical properties. The fabricated immunosensor measures over a wide linear range of 0.01–100 ng mL−1with a low detection limit of 0.9 ± 0.2 pg mL−1. Moreover, the immunosensor demonstrates excellent performance for detecting ancient wool. The identification of wool fabrics unearthed from Xinjiang, Tibet and Kazakhstan supports the historicity of prosperous sheepherding and wool trade in Central Asia during the Bronze Age.

In this work, a method has been presented to analyze the influence of control saturation and structural flexibility on the stable radius of highly flexible aircraft. A dynamic model of aircraft is constructed followed by the analysis of kinetic characteristics. In this paper, the closed-loop stability boundary of highly flexible aircraft with open-loop instability is studied. The amplitude limit and bandwidth limit of the control signal are considered in the closed-loop stability boundary calculation. Our analysis shows that the boundary is related to the left eigenvector corresponding to the unstable poles and the amplitude constraint of the control signals. Stability of the boundary of feedback control system further reduces the limitation of the bandwidth of actuators. Focused on the phugoid instability of highly flexible aircraft, computational formulation of the closed-loop stable boundary is achieved. The Monte Carlo analysis has been employed to validate the stable region, under the LQR controller. Both the theory and simulations have nice correlations with each other which verify the stability of the closed-loop system, restricted by the open-loop system, and the influence of control signal bandwidth constraints.

Species identification is of key significance for exploring the origin and transmission of ancient silks. In this study, two novel methods, i.e.western blot (WB) and proteomics analyses, were proposed and established to identify the differences between silks from Bombyx mori(B. mori) and two other distinctive species (Eri silkworm and Chestnut silkworm). Three diagnostic antibodies, a polyclonal anti-silk fibroin (anti-SF) antibody (pAb), a polyclonal anti-SF-specific peptide antibody (pAsb), and a monoclonal anti-SF antibody (mAb) were designed and prepared to distinguish silk species using the antibody-based WB technique. Proteomics analysis by liquid chromatography–tandem mass spectrometry was performed to further identify silk species at the protein level. WB results indicated that the three antibodies showed high specificity and affinity and could discern B. morisilk from Eriand Chestnutsilks. Biomarkers for each SF were obtained using proteomics analysis, and they have the potential to serve as standards for identifying silk species. Thus, combining WB and proteomics analyses with conventional methods can provide more accurate silk information and may be suitable for identifying other proteinaceous materials in archaeological field.

An integrated approach that considers the performance limitations of tracking control systems for air-breathing hypersonic vehicles is proposed. First, a set of ascent trajectories is obtained as candidates for tracking control through a trajectory design method that considers the available acceleration. Second, the basic theory of performance limitations, which is adopted to calculate the limits on control performance through the trajectory, is integrated. The open-loop dynamics of air-breathing hypersonic vehicles is responsible for these limits on the control system. Comprehensive specifications on stability, tracking accuracy, and robustness are derived, and the flight envelope with constraints and control specifications is identified. Simulation results suggest that trajectory design should consider restrictions on control performance to obtain reliable solutions.

Hypersonic vehicles (HSVs) exhibit significant advantages over other vehicles, including the wide range of velocity and large airspace types, and these features have contributed to the rapid development of HSVs in the last 20 years. Moreover, hypersonic technologies have become a multidisciplinary research topic in the fields of aerodynamics, propulsion, structure, material, and control. Different types of re-entry gliding, air-breathing cruise, and aerospace vehicles have been designed to realize ambitious tasks, which in turn influenced the technological advancements and process change in the military. This paper summarizes the control-oriented integrated design of HSVs. First, the status of current research on the distinct characteristics and technique issues of HSVs is introduced. Then, the progresses made on complex modeling, guidance and control, and trajectory optimization are elaborated to exhibit the significant research interest in hypersonic technologies. The control-integrated design of HSVs is emphasized to solve the multidisciplinary design problems associated with the model and its control and trajectory. Various strategies regarding the multidisciplinary optimization design are also proposed to solve the integrated design problem. Finally, suggestions are provided for the control-oriented integrated design of HSVs.

The use of wool from sheep is widespread in ancient and historic textiles. The detection of ancient wool can provide meaningful information for both archaeologists and academics. However, the efficacy of conventional methods is likely to be limited in the detection of ancient samples with severe degradation or contamination. This is also one of the main challenges in archaeological sites. In this study, a novel immunological approach was proposed to overcome this difficulty. Two diagnostic antibodies, the anti-K (keratin) antibody and the anti-P (peptide) antibody, were carefully designed and prepared through the immunization of animals with a complete antigen (keratin) and the conjugation product of hapten (diagnostic peptide) with a carrier protein, respectively. Next, an indirect enzyme-linked immunosorbent assay (ELISA) was established under the optimal binding concentration of the coating antigens and the antibodies. The results indicated that the antibody-based immunological method exhibited high sensitivity, specificity and reliability. The limit of detection in the ELISA for the anti-K and anti-P antibodies was 81.39 ng mL−1and 6.81 ng mL−1, respectively. The ELISA revealed a lower cross-reactivity (less than 0.01%) for the two antibodies with interference antigens. The recoveries of the two antibodies from standard soil samples were in the range of 80% to 100%, with a relative standard deviation (RSD) of lower than 9%. The coefficients of variation for the anti-K antibody and anti-P antibody were in the range of 3.27% to 12.40% and 9.48% to 10.31%, respectively. Moreover, both the anti-K and anti-P antibodies can positively identify ancient wool samples, even for wool traces in soil, verifying the validity and practicability of the immunological method in the detection of ancient wool.

This paper models the Mars UAV formation exploring the surface of Mars, and then the formation obstacle avoidance is brought up with the assumptions of the Mars circumstance and the UAVs. Based on their specialty, constrained Delaunay triangulation, Yen-Kshortest path algorithm, the collaborative function, and the improved pigeon-inspired optimization (PIO) algorithm are integrated to solve the obstacle avoidance for the formation. Since the steering maneuver costs much energy and increases instabilities vulnerable in extraterrestrial exploration, the paper focuses on the route smoothness problem. The PIO is improved to be suitable for smooth routes and is compatible with other PIO variants. The simulation results show that the sum of the steering angle, namely the performance index, is effectively reduced and satisfies the obstacle avoidance requirements for Mars UAV formation.

A novel hybrid quantum-based pigeon-inspired optimization (PIO) algorithm for global numerical optimization is proposed to perceive deceptiveness and preserve diversity. In the proposed algorithm, the current best solution is regarded as a linear superposition of two probabilistic states, namely positive and deceptive. Through a quantum rotation gate, the positive probability is either enhanced or reset to balance exploration and exploitation. Simulation results reveal that the hybrid quantum-based PIO algorithm demonstrates an outstanding performance in global optimization owing to preserving diversity in the early evolution. As a result, the stability of the algorithm is enhanced so that the precision of optimization is improved statistically. The proposed algorithm is demonstrated to be effective for solving multimodal and non-convex problems in higher dimension with a smaller population size.

The emphasis of this article lies in the development of a gain scheduling algorithm for the constant dynamic pressure ascent trajectory. Due to the broad flight envelope and nonlinear characteristics of hypersonic vehicles, a design method of adaptive control based on guardian maps is proposed. Two types of ascent trajectory are considered: acceleration within Scram mode and acceleration across the Ram–Scram mode transition. A velocity-based linear parameter varying model of an air-breathing hypersonic vehicle is established. The gain vector of controller is determined via optimal control theory based on linear quadratic regulator technology with the specified flying qualities. With the iteration of proposed guardian maps approach, the set of controller gain vector within the flight envelope is obtained. The results of nonlinear simulation show that the proposed approach of control system design has the ability to ensure the global stability through the flight envelope and to maintain the flying qualities.