最新刊期
卷 47 ， 期 4 ， 2026
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机器人机构设计与控制专栏 AI导读
- 摘要：Regarding the current issue of high labor costs associated with perilla seed sowing， a perilla quadruped seeding robot based on the （2-UPU/RPU） & U mixed coupling mechanism was proposed， so as to enable it to complete the perilla seeding operation instead of manual work. Firstly， the spiral theory and K-G formula were used to solve and verify the degree of freedom characteristics of the 2-UPU/RPU parallel mechanism. And the inverse solution analysis of the parallel mechanism was applied by the closed vector method to establish the velocity Jacobi matrix model and analyze the existence conditions of the mechanism’s singularity. Then the workspace at the foot end of the robot was solved by the limiting boundary search method， and the motion/force transfer performance analysis was carried out. Finally， different sowing point positions were set， and MOTION in SOLIDWORKS was utilized to simulate its movement. The results show that the mechanism’s workspace is internally continuous， and there is no singular position， the transfer performance is good， and it has the flexibility of adjusting the foot-end plant spacing and row spacing as well as the ability of adapting to the terrain. It provides a new solution for the mechanization and intelligent development of perilla planting.关键词：perilla;quadruped seeding robot;kinematics;SOLIDWORKS28|16|0更新时间：2026-07-31
- 摘要：In order to make up for the shortcomings of the current parallel robot experimental platform， such as weak flexibility and inability to expand. A “virtual-real” complementary digital twin model based on modular reconfigurable robot innovative components was proposed， and an experimental platform for the 6-SPS parallel mechanism with virtual-real combination， complementary functions and mutual verification was designed. The theoretical models of displacement， velocity and acceleration of the 6-SPS parallel robot were established， and the Jacobian matrix of the mechanism was obtained. A trajectory was planned， and the consistency between the theoretical model and the real running trajectory was verified through experiments. The maximum reachable working space of the robot was analyzed， and based on this， the kinematic performance of the mechanism of the robot in a fixed attitude and any attitude was analyzed. The experimental platform was applied to experimental teaching. Through the combination of virtual and real methods， problems such as tight experimental venues and insufficient experimental equipment were solved， increasing the application rate of equipment and improving the effect of experiments. Practice shows that this experimental method， which is intuitive， vivid and combines virtual and real elements， is conducive to enhancing students’ exploration interest and engineering practice ability.关键词：parallel robot;modular reconfigurable;virtual-real synthesis;dexterity27|16|0更新时间：2026-07-31
- 摘要：The swimming velocity of fish can be adjusted by tail-beat frequency and swing， how to determine the optimal tail-beat frequency and swing of specific swimming velocity is of great significance for understanding the swimming mechanism of fish and improving the range of bionic vehicles such as robotic fish. Using the ghost-cell immersed boundary method with adaptive mesh， the self-propelled swimming of fish under different tail-beat frequencies and swings is numerically simulated， and the effects of frequency and swing on the unit energy consumption are analyzed. The results show that the relationship between swimming velocity and tail-beat frequency is approximately linear under the same tail-beat swing. Under the condition of the same swimming velocity， the energy consumption required per unit distance with different tail-beat swings varies significantly， with a maximum difference of 2.5 times， the energy consumption does not change monotonously with tail-beat swing and there is an optimal tail-beat swing of energy-saving. When the swimming velocity is 1.5 non-dimensional units， the optimal tail-beat swing is 0.07 times the body length. The optimal tail-beat swing decreases with the increase of swimming velocity， being regarded as a constant value in a certain range of swimming velocity. For example， when the swimming velocity is between 1.0 and 2.0 non-dimensional units， the optimal tail-beat swing remains between 0.05 and 0.07 times the body length. Therefore， the most energy-efficient swimming mode for fish is as follows： based on a segmented regulation strategy for swimming velocity intervals， the corresponding optimal tail-beat swing is matched within different velocity ranges， and the specific swimming velocity is adjusted by tail-beat frequency.关键词：self-propelled swimming;unit energy consumption;swimming velocity;tail-beat frequency;tail-beat swing16|13|0更新时间：2026-07-31
- 摘要：In dynamic explosion tests， the random offset of the detonation center leads to variable incident directions of shock waves and a wide span of pressure amplitudes. This results in significant variations in the incident angle of the sensor and large fluctuations in the overpressure amplitude at measuring points. Conventional testing devices can hardly meet the requirements of both omnidirectional response and high-precision wide-range measurement simultaneously.To address the above engineering challenges， this paper develops a free-field shock wave overpressure testing device with dual adaptability in direction and range. The device adopts a “lollipop” structure and uses a spherical piezoelectric ceramic with a diameter of 15 mm as the sensing unit. By utilizing the uniform sensitivity characteristic of the spherical surface， an approximately omnidirectional response to overpressure within an incident angle range of ±90° is achieved. The signal conditioning module integrates a range adaptive control circuit， builds a four-channel parallel acquisition structure， and realizes the adaptive selection of the optimal range channel based on amplitude determination， which achieves a balance between the measurement accuracy in the low-pressure section and the overload resistance capacity in the high-pressure section， and realizes high-precision measurement and range adaptive matching of shock wave signals within a wide dynamic range. The performance of the device is verified by a combination of shock tube dynamic calibration and explosion tests. Experimental results show that the dynamic sensitivity of the sensor is 83.2 μV/Pa， and the sensitivity attenuation is less than 3% within the incident angle range of ±90°. Stable and reliable free-field overpressure measurement can still be realized under the conditions of random detonation center offset and large variations in shock wave intensity.This study provides a novel sensing technical solution for wide-range and omnidirectional shock wave measurement in dynamic explosions， and validates the feasibility and engineering practical value of the dual-adaptive sensing principle in explosion testing.关键词：dynamic blast testing;spherical piezoelectric sensor;adaptive reading;shock wave overpressure;wide-range measurement724|17|0更新时间：2026-07-31
- 摘要：In traditional Hopkinson bar impact tests， the interaction between the projectile and the bar primarily involves transient elastic collisions. This limits the controllable range of the incident stress pulse width， making it difficult to meet the testing requirements for mechanical overload impacts at the hundred-microsecond scale. This paper proposes a controlled pulse width expansion impact testing method using 8800M polyurethane as the waveform shaper material. This method introduces a polyurethane waveform shaper at the bullet-impact rod interface to modulate initial contact conditions and stress wave formation. This transforms the transient elastic collision into a non-transient contact behavior with significantly extended duration and controllable process， thereby achieving a smoother rise of the impact pulse and effective pulse width expansion. A finite element model of the bullet-shaper-impact rod system was established using the finite element method. Key parameters such as shaper thickness （from 1 to 10 mm） and bullet initial velocity （from 14 to 20 m·s-1） were systematically analyzed to investigate their influence on pulse peak and width. Thickness was identified as the dominant parameter for pulse width control， with a linear effective range of from 1 to 5 mm for pulse width expansion when the waveform shaper diameter is 10 mm. Simulation and experimental results demonstrate that the polyurethane waveform shaper achieves a relative standard deviation of 3.28% in pulse width during repeatability tests， enabling significant pulse width expansion while maintaining stable waveform characteristics. The average pulse widths obtained under various operating conditions exhibit excellent consistency with simulation results， with a maximum relative error of 3.25%， thereby validating the established model and research methodology.关键词：Hopkinson bar;pulse width-peak;polyurethane;waveform shaping;mechanical overload581|17|0更新时间：2026-07-31
- 摘要：For the problem that the shock-wave propagation characteristics have significant differences with ground explosion under airburst conditions， and traditional shock-wave test devices are difficult to be applicable to in-air deployment and multi-direction shock-wave measurement， a lightweight airburst shock-wave test system was designed and developed. This system took the radially polarized spherical piezoelectric sensor as the core sensitive unit， and used its geometrical symmetric structure to realize omnidirectional response measurement of shock-wave overpressure signals. A storage-type test system composed of signal-conditioning circuit， high-speed analog-to-digital conversion module， spatial-information acquisition module and local storage unit was constructed， realizing automatic triggering， high-speed acquisition and local recording of shock-wave signals. The system sampling rate was 1 MSPS， the analog-to-digital conversion resolution was 12 bit， and through compact structure design and lightweight packaging， the whole device could meet the test requirements of in-air suspended deployment. Through suspended outdoor explosion tests， the system performance was verified， under different explosion heights and azimuth-angle conditions， the test system could stably acquire complete shock-wave overpressure time-history curves. The test results show that the shock-wave overpressure peak values recorded by each measuring point are distributed concentratedly， the relative standard deviation is 4.8%， and the system has good dynamic response ability and measurement consistency. The developed test system can stably acquire shock-wave pressure time-history data under in-air environment， and can provide an effective test means for airburst shock-wave propagation law research and high-altitude damage-effect evaluation.关键词：airburst experiments;shock wave overpressure measurement;spherical omnidirectional sensor682|15|0更新时间：2026-07-31
- 摘要：A projectile targeting coordinate detection algorithm was proposed based on the Transformer architecture to address the problem of insufficient positioning accuracy in complex occlusion scenarios in photoelectric coordinate detection systems. The algorithm combined FPGA for signal acquisition and preprocessing， and leveraged the powerful feature extraction capability of the Transformer to optimize photoelectric coordinate detection accuracy. The system used a 1 m×1 m measurement light curtain composed of narrow-beam infrared emitter SFH 4550 and PIN photodiode arrays. It captured the photoelectric signals generated by the projectile’s obscuring beam to construct a complete algorithm framework of “signal acquisition - feature modeling - coordinate prediction”. The 8-bit binary sensor states were transformed into high-dimensional features through linear projection and positional encoding， and processed in the Transformer’s multi-head attention mechanism to effectively capture spatial relationships between different sensors. By acquiring and preprocessing signals with FPGA and performing feature modeling and coordinate prediction with the Transformer model， the system achieved accurate coordinate computation.Experimental results show that the proposed algorithm achieves high positioning accuracy in both single-point and multi-point occlusion scenarios， with the predicted coordinate error range controlled within ±1.5 mm. Compared with existing systems， the accuracy is significantly improved. Measurement verification based on high-precision coordinate target paper shows that the experimental accuracy meets practical application requirements， providing reliable technical support for the refinement and optimization of modern weapon systems. In addition， by comparing different models， the results validate that the Transformer-based feature extraction method in complex occlusion scenarios has good robustness and real-time performance.关键词：photoelectric coordinate detection;Transformer;FPGA;coordinate calculation33|22|0更新时间：2026-07-31
- 摘要：To address the challenge of balancing high transfection efficiency with low cytotoxicity and poor serum stability in polyethylenimine （PEI）-based gene carriers， low molecular weight polyethyleneimine （PEI， 600 u） was employed as the cationic core and grafted onto biodegradable PEG-like polyester backbones with varying chain lengths （diethylene glycol， triethylene glycol， tetraethylene glycol and pentaethylene glycol）， successfully constructing four novel polymers designated as L1 to L4. The chemical structures of the obtained polymers were characterized by proton nuclear magnetic resonance （1H NMR）， while their molecular weight distributions were determined by gel permeation chromatography （GPC）. Furthermore， the DNA binding affinity of these polymers was evaluated by agarose gel electrophoresis. In addition， three cell lines—cervical carcinoma （HeLa）， human osteosarcoma （U2OS） and hepatocellular carcinoma （HepG2） served as in vitro models for evaluating the transfection efficiency of the polymer/DNA complexes under serum-free conditions using green fluorescent protein expression from the pEGFP-N1 reporter gene， with PEI 25 ku serving as a positive control. Both 1H NMR and GPC analyses confirmed the successful synthesis of the target polymers. Gel electrophoresis indicated that all polymers exhibited good DNA-binding ability. In vitro transfection experiments demonstrated that polymer L3 achieved the highest transfection efficiency across all three cell types. Notably， in U2OS cells， the entire series of polymers demonstrated significantly higher transfection efficiency than PEI 25 ku. This study provides a new material design strategy for developing non-viral gene carriers with high efficiency， low toxicity， and enhanced stability.关键词：gene vector;PEG-like structures;biodegradable;low molecular weight PEI21|16|0更新时间：2026-07-31
- 摘要：Tea biochar magnetic materials were synthesized by co-precipitation method and characterized by FT-IR and XRD， and applied to the study of Cr（Ⅵ） removal from aqueous solution. The effects of reaction conditions on Cr（Ⅵ） adsorption were investigated， and the kinetics and isothermal adsorption fitting of its adsorption process were carried out. The results showed that at room temperature， the optimal adsorption conditions were pH=1， adsorbent dosage of 0.025 g， mass concentration 60 mg·L-1， ultrasonic power 250 W， and ultrasonic time 40 min. Under these condition， the removal rate of Cr（Ⅵ） was 90.93%， with adsorption capacity of 43.64 mg·g-1. The removal rate can still reach 70.91% after three cycles. This adsorption process conforms to the quasi-second-order kinetic adsorption equation and the Langmuir isothermal adsorption model， which is a monolayer chemical adsorption. Chelation and electrostatic interaction are the main adsorption mechanisms. This material has a simple preparation process， cheap and easy raw materials， a high adsorption capacity for Cr（Ⅵ） in water and is convenient for magnetic recovery. It has potential application value in the green treatment of heavy metal pollution in water.关键词：tea biochar;magnetic material;Cr（Ⅵ）;adsorption10|12|0更新时间：2026-07-31
- 摘要：In a confined space， the breathing of personnel will continuously produce CO2. In this environment， the partial pressure of CO2 is low， which results in a small driving force for absorption mass transfer. Moreover， traditional organic amine absorbents are highly corrosive and volatile， producing an irritating odor. Therefore， it is crucial to develop a green and efficient CO2 absorbent with excellent absorption performance and safety and environmental protection. In this paper， a mixed solution of potassium hydroxide （KOH） and potassium glycinate （GlyK） was used as a composite absorbent to conduct low volume fraction CO2 （simulating the actual volume fraction in a closed space） absorption experiments under bubble column and high-gravity reactor conditions. The effects of factors such as absorbent concentration and reaction temperature on the absorption performance were systematically evaluated. The influence of GlyK addition on the absorption rate， absorption capacity and removal rate was analyzed. The experimental results show that at normal temperature and pressure， the addition of GlyK significantly enhances the absorption effect of low-concentration CO2： compared with the single KOH solution， in the bubble reactor， the removal rate of the composite absorbent increases by 10%， and the absorption load increases by 208%； under the high-gravity condition， the removal rate of the KOH solution increases by 20 percentage points， and the CO2 volume fraction can be absorbed to 500×10-6； the absorption load is 0.105 5 mol·mol-1， increasing by 173%. This study proposed a composite absorbents with high absorption efficiency and environmental friendliness. A comprehensive evaluation of its absorption performance can significantly enhance life support efficiency in enclosed environments such as submarines and spacecraft， reduce energy consumption through green recycling， extend survival and mission durations， and provide technical reserves for addressing climate change.关键词：CO2;absorbent;KOH;potassium glycinate;high-gravity675|13|0更新时间：2026-07-31
- 摘要：Composites have been increasingly applied in aerospace and engineering construction due to their multi-physical field coupling and anisotropic characteristics. However， their complex nonlinear structures posed significant challenges to the traditional research and development paradigm. The conventional trial-and-error approach， which relied heavily on physical experiments， was limited by long cycles， high costs， and difficulties in exploring the vast design space. The introduction of machine learning technologies brought novel research insights to materials science， enabling the exploration of the deep structure–property relationships of materials through a data-driven approach. This study aims to provide a systematic review of the current application status and transformative potential of machine learning in composite materials research， structured across three primary dimensions： structural design， performance characterization， and process optimization. The article first elucidated how high-fidelity surrogate models developed through machine learning significantly enhanced the efficiency of optimizing structural design parameters. Furthermore， it introduced breakthroughs in multi-scale performance characterization， delving into the research frontiers by exploring data-driven performance prediction and the utilization of deep learning architectures for the precise formulation of constitutive relations. Finally， the paper discussed intelligent manufacturing technologies of composites based on intelligent regulation of process parameters and intelligent scheduling in the production flow. It points out the challenges and future development directions of further promoting composites research using machine learning in view of current data quality， model interpretability， and industrial chain integration in the machine learning field.关键词：machine learning;composites;structural design;performance characterization;intelligent manufacture14|18|0更新时间：2026-07-31
- 摘要：To address the issues of temporal feature loss caused by traffic visualization and the insufficient detection accuracy of lightweight models under complex attacks in network intrusion detection， a lightweight model named MobileViT-AESTF was proposed based on recurrence plot （RP） and an adaptive efficient spatiotemporal fusion （AESTF） module. Utilizing phase space reconstruction technology， the method mapped one-dimensional traffic time series into recursive relationships in a two-dimensional state space via RP， effectively retaining the non-linear temporal features of the traffic. To overcome the insufficient feature capture capability of MobileViT_V3 in processing visualized traffic， the designed AESTF module comprised an efficient spatiotemporal fusion （ESTF） unit and an adaptive feature exciter （AFE）； specifically， the ESTF employed a dual-path heterogeneous attention mechanism to extract spatial and channel features in parallel， while the AFE adaptively enhanced key discriminative features based on a neuronal energy function. Experimental results on the CIC UNSW-NB15 Augmented dataset demonstrate that MobileViT-AESTF achieves an accuracy， recall， and F1-score of 99.84%， 99.82%， and 99.85% respectively， while maintaining a low parameter count of 1.04×106. Compared with the baseline MobileViT_V3， the proposed model reduces computational cost and exhibits greater robustness in identifying complex attacks such as Fuzzers. The model achieves an effective balance between lightweight design and detection accuracy， making it suitable for network intrusion detection in resource-constrained environments and offering significant engineering application value.关键词：intrusion detection;image classification;lightweight network;MobileViT313|18|0更新时间：2026-07-31
- 摘要：Class imbalance in network intrusion detection makes minority attack classes particularly challenging to identify. To address this issue， we proposed META-VAEGAN-DNN， a novel intrusion detection framework that integrated meta-learning with a variational autoencoder generative adversarial network （VAE-GAN）. A META-VAEGAN-based augmentation model was first developed to alleviate class imbalance， followed by a differentiated sample processing strategy with a progressive quality filtering mechanism designed to enhance the generation of minority-class instances. The augmented data were then classified using a deep neural network （DNN） enhanced with channel attention and multi-layer residual connections. Experiments on the NSL-KDD dataset demonstrate that META-VAEGAN-DNN achieves 89% accuracy， 90% F1-score， and 98% AUC. Notably， the precision and recall of the U2R class reach 98% and 99%， respectively， while those of the R2L class reach 99% and 73%， substantially outperforming conventional methods. These results highlight the effectiveness of META-VAEGAN-DNN in improving the detection of minority attack categories and enhancing overall intrusion detection performance. Supplementary validation on the CIC-IDS-2017 dataset further demonstrates the generalizability of the model.关键词：variational autoencoder;generative adversarial network;meta-learning;intrusion detection317|19|0更新时间：2026-07-31
- 摘要：As a core means for high-fidelity detection of extremely weak optical signals， single-photon detection technology is a key support for cutting-edge fields including quantum communication， quantum computing， quantum radar， and biomedical imaging. Its performance directly determines the depth of fundamental optical quantum research and the breadth of industrial applications. This paper systematically reviews the physical mechanisms of single-photon detection： external photoelectric effect with multi-stage multiplied electron emission， internal photoelectric effect with carrier avalanche multiplication effect， and the photon-induced hot electron effect， which correspond to typical devices such as photomultiplier tubes （PMTs）， single-photon avalanche diodes （SPADs）， and superconducting nanowire single-photon detectors （SNSPDs）. The physical implications and engineering values of key performance parameters of single-photon detectors are analyzed in detail. Focus is placed on elaborating the circuit designs of these devices： high-voltage voltage-dividing power supply， low-noise preamplification and filtering circuits for PMTs； passive， active， hybrid， and gated quenching circuits for SPADs； and readout circuit solutions for SNSPDs （including traditional 50 Ω room-temperature architecture， latch-up effect suppression， and optimized double-ended readout）. Finally， the core challenges facing single-photon detection technology are summarized， such as dark count suppression， after-pulse effect control， the trade-off between detection efficiency and response speed， and cost and engineering adaptability， providing a reference for technological breakthroughs and application expansion in this field.关键词：single-photon detector;photoelectric effect;avalanche multiplication effect;circuit design10|14|0更新时间：2026-07-31
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Adaptive DFT Channel Estimation Algorithm Based on Joint Delay and SNR Estimation in OFDM System AI导读
摘要：Aiming at the problems of traditional Discrete Fourier Transform channel estimation algorithms in orthogonal frequency division multiplexing systems， such as fixed use of cyclic prefix length， severe energy leakage under non-integer delay channels， and insufficient noise suppression， an improved adaptive threshold DFT algorithm based on joint delay and signal-to-noise ratio estimation was proposed. Based on the initial least square estimation， the algorithm introduced the multiple signal classification super-resolution technology to achieve accurate estimation of channel multipath delays， and dynamically determined the optimal time-domain denoising window according to the actual maximum delay， thus getting rid of the dependence on fixed CP length. Based on the dynamic window， the pure signal interval and noise interval were re-divided， the signal power and noise power were accurately calculated to realize reliable SNR estimation， and the estimated SNR value was used as the core basis to construct an adaptive denoising threshold， and noise suppression and signal protection were completed through two-stage time-domain filtering. Finally， the final channel response was obtained through frequency-domain transformation and window function compensation. Simulation results show that under Rayleigh multipath fading channels， compared with the traditional DFT algorithm and fixed threshold algorithm， the mean square error and bit error rate are significantly reduced， and the performance improvement is particularly obvious in medium and high SNR and non-integer delay scenarios. The algorithm realizes the joint adaptive optimization of delay estimation， window length and denoising threshold， which effectively improves the channel estimation performance. However， affected by the characteristics of the MUSIC algorithm， the overall computational complexity is higher than that of traditional methods， which has certain limitations in delay-sensitive scenarios， and further research will focus on complexity optimization in the future.关键词：orthogonal frequency division multiplexing;channel estimation;signal-to-noise ratio estimation;adaptive threshold;multiple signal classification algorithm11|13|0更新时间：2026-07-31 -
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