NetWork
Construction and practice of an experimental project-driven total-factor collaborative safety access mechanism for university laboratories
BAI Li;LI Chunhui;WANG Peng;YU Hao;[Objective] University laboratories serve as the core carriers for scientific innovation and talent cultivation; however， they face significant safety challenges due to the complex nature of research and the high mobility of personnel. According to a statistical analysis of 137 laboratory safety accidents at Chinese universities and research institutes between 2004 and 2024， 62.04% of incidents stemmed from improper personnel operations. Additionally， over 80% involved a “lack of factor collaboration，” in which the failure to coordinate multiple safety elements expanded the scope of harm. Traditional management models often suffer from “single-point fragmented control，” in which personnel， hazardous materials， environmental conditions， and experimental projects are managed in isolation. This lack of synergy cannot address the dynamic， multidisciplinary nature of modern university research; therefore， a systematic governance mechanism is urgently required. This study constructs a “total-factor collaborative safety access mechanism” that integrates the social amplification of risk framework and synergistic theory to transform laboratory safety management from passive， fragmented control to active， systematic governance. [Methods] Based on the “order parameter” principle of synergistic and the environment， health， and safety integration model， this study constructs a closed-loop linkage mechanism characterized by “perception–assessment–linkage–feedback.” The core innovation lies in treating the “experimental project” as the system’s critical “order parameter.” The mechanism drives the precise adaptation of three other key access elements: personnel， items， and the environment. First， to ensure personnel access， a “three-level classification–dynamic adaptation” training system was developed. Based on the specific project’s risk level， personnel undergo stratified training (university， college， and laboratory levels). A dynamic reverification mechanism ensures that operator qualifications align with changing project risks. Second， for item access， a “full lifecycle–multidimensional tracing” system was implemented. RFID and QR code technologies were used to manage hazardous chemicals and equipment from procurement to disposal， ensuring strict compliance with project needs. Third， for environmental access， laboratories were classified into five categories (e.g.， chemical， biological， and mechanical) with a “planning–auditing–acceptance” control flow to ensure that physical conditions meet the safety requirements of the proposed projects. Finally， to assess overall project access， a quantitative risk assessment system comprising 4 primary and 12 secondary indicators was established. An information platform serves as the technical backbone， enabling real-time data sharing and automatically triggering safety protocols when project parameters change. [Results] The proposed mechanism was validated through practical application at Shandong University of Science and Technology. A specific case study involved the “nano-sulfide synthesis experiment” at the College of Chemical Engineering in September 2024. Due to a change in the experimental scheme involving the addition of hydrogen sulfide gas， the project’s risk level rose from “low risk” to “high risk.” The collaborative mechanism immediately triggered a dynamic reverification process for the 12 original operators. The assessment included a theoretical evaluation (40% weight) and practical operation (60% weight)， focusing on toxic gas handling and emergency response to leaks. The results showed that 11 operators passed the reverification; however， 1 operator failed the practical test for failing to check the air-tightness of the positive-pressure air breathing apparatus before use. Consequently， the system automatically suspended this operator’s laboratory access authority. The operator was required to complete 30 h of specialized remedial training and pass a secondary assessment to regain access. This case demonstrated the mechanism’s ability to identify specific unsafe behaviors and dynamically manage risks. [Conclusions] The “total-factor collaborative safety access mechanism” successfully overcomes the limitations of traditional siloed management by using the experimental project as the driving force for systemic safety. By integrating personnel， items， and environmental factors into a cohesive， project-driven framework， the mechanism achieves precise risk control and dynamic adaptation. Practical application proves that this approach effectively shifts safety management from “passive response after accidents” to “active defense before risks.” This study provides a replicable and scalable paradigm for safety governance in multidisciplinary comprehensive universities， particularly those with intensive， high-risk experimental activities in fields such as chemistry and biology.
Preparation of flexible pressure sensors for intelligent sensing terminals and interdisciplinary comprehensive experimental teaching design
XIA Shengyuan;GUO Baohong;SHEN Qingbin;SUN Hao;WANG Wu;[Objective] Rapid advances in intelligent wearables， mobile healthcare， and integrated energy systems have increased demand for flexible， highly sensitive， and environmentally friendly sensing terminals. Traditional pressure sensors， often based on metals or semiconductors， face significant limitations， including poor flexibility， limited sensitivity， complex fabrication， and recycling challenges， which hinder their use in next-generation intelligent systems. Concurrently， cultivating interdisciplinary talent with integrated innovation and practical engineering skills is urgent. However， current sensor-related experimental courses often lack comprehensive training that spans material synthesis， device fabrication， system integration， and application. This study aims to address these dual challenges by developing a high-performance， eco-friendly flexible pressure sensor and transforming the corresponding research outcomes into a structured interdisciplinary experimental teaching project， thereby bridging the gap between advanced research and engineering education. [Methods] A sandwich-structured flexible pressure sensor was designed and fabricated using reduced graphene oxide (rGO-impregnated fabric as the active sensing layer and laser-induced graphene (LIG) as the porous top and bottom electrodes. The rGO fabric was prepared via a simple soaking–thermal reduction process， in which a piece of cotton-linen blend fabric was immersed in a graphene oxide dispersion and subsequently thermally reduced at 200°C. The LIG electrodes were directly patterned onto polyimide (PI) films using a CO2 laser engraving system， creating a three-dimensional porous conductive network. The sensor was assembled by sandwiching the rGO fabric between two LIG/PI electrodes. The morphology and composition of the rGO fabric and LIG were characterized using scanning electron microscopy (SEM)， X-ray photoelectron spectroscopy， and Raman spectroscopy. The sensor’s electromechanical performance， including sensitivity and stability， was systematically evaluated using a universal testing machine coupled with a digital source meter. The sensor’s practical application potential was demonstrated by detecting static forces with standard weights and by monitoring dynamic physiological signals to capture human radial artery pulse waveforms. [Results] The fabricated sensor exhibited excellent overall performance. The rGO formed a continuous conductive coating on the fabric fibers， while the LIG exhibited a highly porous and interconnected structure， enabling efficient signal transduction. The sensor demonstrated a high sensitivity of 30.3 kPa-1 in the low-pressure range (0–5 kPa). It showed outstanding stability， with negligible performance degradation over 300 loading–unloading cycles at 5 kPa. The sensor could clearly distinguish static loads and reliably capture dynamic physiological signals. The pulse waveform displayed characteristic peaks， from which a heart rate of approximately 72 beats per minute was derived， consistent with the resting state of a healthy adult. This interdisciplinary experiment， integrating knowledge from electrical engineering， materials science， and biomedical engineering， was successfully implemented as a teaching module. It guided students through the complete research cycle， from design and fabrication to testing and application analysis. The teaching practice achieved important outcomes， including supporting student teams in obtaining National-level University Student Innovation Training Program projects and winning a provincial silver medal in the China International College Students’ Innovation Competition. [Conclusions] This work successfully developed an eco-friendly， low-cost， high-performance flexible pressure sensor based on rGO fabric and LIG porous electrodes. More importantly， it established an effective model for translating cutting-edge research into a comprehensive interdisciplinary experimental teaching project. This project addresses the shortcomings of traditional sensor experiments by offering students hands-on experience throughout the device development workflow. It effectively enhances students’ interdisciplinary integration capabilities， practical engineering skills， and innovative thinking， thereby offering a reproducible and scalable educational paradigm for cultivating interdisciplinary talent under the emerging engineering education initiative.
Harnessing STA-IR-MS for the experimental teaching of energy materials:A case study on the thermal stability of lithium-based polymer electrolyte materials
SHI Chuqi;ZHANG Weibin;YANG Qin;PAN Yikun;[Objective] The growing prominence of advanced analytical techniques in materials science has underscored the need to integrate coupled instrumentation systems into graduate education. Introducing synchronous thermal analysis (STA) combined with infrared spectroscopy (IR) and mass spectrometry (MS) into experimental teaching is an important initiative for cultivating interdisciplinary talent capable of addressing complex research challenges in energy materials development. [Methods] This study systematically examines the architectural principles and operational mechanisms of STA-FTIR-MS and STA-FTIR-GC-MS (gas chromatography-MS) coupled technologies， demonstrating their distinctive advantages in energy materials education through an integrated teaching experiment focused on the Thermal Stability of Lithium-based Polymer Electrolyte Materials.” The experiment was designed to cultivate comprehensive skills in multimodal data acquisition and interpretation and was structured around four fundamental components. These include establishing learning objectives to familiarize students with the working principles of STA， FTIR， MS， and GC–MS systems while demonstrating correlations among mass loss， thermal events， and gas evolution to develop capabilities in analyzing complex multidimensional datasets; implementing experimental procedures in which students prepare lithium-based polymer electrolyte samples and subject them to programmed heating under an inert atmosphere， with the STA module recording real-time mass changes and enthalpy variations and evolved gases simultaneously transferred via a heated transfer line to FTIR and MS/GC-MS systems for compositional identification and quantification; facilitating integrated data analysis in which trainees learn to synchronize thermogravimetric data with FTIR spectral profiles and MS/GC–MS to establish causal relationships between thermal decomposition stages and specific gas release events， while enabling direct comparison of the analytical capabilities of MS and GC-MS detection systems in characterizing thermal decomposition processes; and conducting teaching assessments through evaluation rubrics that examine laboratory performance， data interpretation accuracy， and final report quality， with particular emphasis on critical reasoning skills and scientific communication abilities. [Results] The integrated experiment enabled students to quantitatively correlate mass loss events with specific gas evolution profiles through synchronized data analysis. During programmed heating， participants identified characteristic decomposition stages—such as solvent evaporation， polymer chain degradation， and inorganic salt decomposition—by cross-referencing STA curves with IR absorption bands (e.g.， C＝O stretching at 1740 cm-1 for carbonate decomposition) and MS ion fragments or GC–MS chromatographic peaks. This approach revealed clear structure-property relationships between material composition and thermal behavior while demonstrating the complementary strengths of MS (rapid detection) and GC-MS (superior resolution for complex mixtures). Assessment based on operational proficiency， data interpretation accuracy， and scientific reporting demonstrated considerable improvement in students’ ability to extract meaningful insights from multidimensional datasets， propose mechanistic explanations for observed phenomena， and communicate findings effectively. The experiment has established a new pedagogical model for advanced instrumental training within the New Engineering Education framework， emphasizing critical thinking and technical problem-solving. [Conclusions] The integration of STA-IR-MS/GC-MS coupled technologies into energy materials laboratory teaching represents a successful reform that goes beyond traditional single-technique experiments. Through this thoughtfully designed project， students gained hands-on experience with state-of-the-art instrumentation and developed a researcher’s mindset. They learned to navigate analytical complexity， reconcile complementary datasets， and construct evidence-based scientific narratives. This pedagogical approach effectively bridges the gap between theoretical knowledge and practical research skills， fostering the interdisciplinary competencies required for innovation in advanced materials science. Moreover， this model offers a scalable framework for future curriculum development and can be adapted to other emerging fields where coupled characterization techniques are essential.
Design and experimental research on energy management strategy for fuel cell vehicles
SUN Ke;SUN Wen;BAI Shuzhan;[Objective] Under the global “Dual Carbon” goals， the transportation sector urgently needs cleaner and more efficient powertrains. Proton Exchange Membrane Fuel Cell (PEMFC) technology， featuring zero tailpipe emissions， high energy density and extended range， has become a key pathway for commercial-vehicle decarbonization. However， the slow dynamic response of PEMFC systems makes it difficult for a stand-alone fuel cell to cope with frequent start–stops and rapid load fluctuations. Therefore， fuel cell–battery hybrid architectures are widely adopted， which place higher requirements on Energy Management Strategies (EMS) to coordinate multi-energy sources efficiently. This study targets the EMS design problem for fuel cell commercial vehicles， and experimentally compares two representative strategies from an engineering perspective to provide a basis for system optimization. [Methods] A hardware-in-the-loop bench platform for a fuel cell hybrid electric vehicle was established. The platform integrates a PEMFC system， a lithium iron phosphate battery pack and a drive motor， together with a dynamic load simulation system to reproduce real-world driving resistances. A self-developed LabVIEW-based software platform combined with CAN bus communication enables real-time driving-cycle replay， data acquisition and EMS verification. On this basis， two EMSs were implemented: a deterministic rule-based strategy and a fuzzy-logic-based strategy (FLC). The rule-based strategy adopts a master–slave architecture that treats the fuel cell as the main power source and allocates power according to total vehicle demand and battery state-of-charge (SOC) thresholds. The FLC takes vehicle power demand and SOC as inputs and outputs fuel cell power， adjusting power distribution via predefined fuzzy rules. [Results] Bench tests under the same driving cycle reveal distinct characteristics for the two strategies. Both achieve similar peak and average motor power， while the FLC exhibits slightly larger power fluctuations and faster tracking of load changes， indicating better dynamic adaptability and smoother acceleration/deceleration behaviour. Under the FLC， the fuel cell operates at lower average power with more frequent start–stops， and the battery undertakes a larger share of power regulation; under the rule-based strategy the fuel cell output is more continuous and often near its rated power， and the battery SOC is maintained within a narrow band， which is beneficial to battery life. Hydrogen-consumption analysis shows that， although the FLC reduces instantaneous fuel cell usage， its higher reliance on battery charge–discharge cycling leads to higher equivalent hydrogen consumption， whereas the rule-based strategy offers shorter energy paths and better overall fuel economy. Quantitatively， the rule-based strategy achieved an actual and equivalent hydrogen consumption of 568.13 g and 628.84 g， respectively， compared with 441.41 g and 726.40 g for the FLC. [Conclusions] The two EMSs present complementary advantages. The FLC is more suitable for urban scenarios with frequent start–stops and rapidly varying loads， where dynamic response and driving smoothness are prioritised. The deterministic rule-based strategy is more appropriate for relatively stable operating conditions that emphasise range and hydrogen economy， thanks to its efficient and stable power-supply characteristics. Future work will focus on adaptive or hybrid EMS frameworks that combine rule-based logic with data-driven or intelligent optimisation methods to enhance multi-scenario applicability and overall energy-management performance of fuel cell hybrid commercial vehicles.
Magnetic-Coupling Nonlinear Internal Resonance: An Inquiry-Based Experimental Teaching Design
TIAN Wei;GAO Xiangguo;WANG Le;YANG Zhichun;[Objective] Aligned with recent developments in the research field， this work develops an exploratory experimental teaching platform specifically designed to investigate nonlinear internal resonance phenomena， with magnetic coupling effects serving as the core and essential mechanism. The primary aim of this platform is not only to enable students to systematically and comprehensively master the fundamental theoretical foundations of nonlinear vibration， but also to further enhance their abilities in independent critical thinking， experimental planning， and problem-oriented design. In addition， the platform guides students through the complete process of structural modeling， theoretical analysis， and experimental validation of internal resonance phenomena， thereby fostering a deeper understanding of the dynamic behaviors involved. [Methods] For the physical experimental setup， double cantilever beam specimens are manufactured using 3D printing technology， and an internal resonance testing platform is subsequently constructed by integrating the specimens with a vibration testing bench， laser displacement sensors， and an LMS data acquisition system. Identical permanent magnets are mounted at the free ends of the two cantilever beams， and the occurrence of internal resonance can be experimentally tuned and controlled by adjusting the stiffness characteristics of the beams. Within the theoretical modelling framework， a magnetic dipole model is employed to characterize and quantify the nonlinear magnetic forces between the magnets. On this basis， the governing equations of the magnetically coupled double-cantilever-beam system are formulated in accordance with Newton’s second law. During experimental testing， constant-amplitude sinusoidal sweep excitation is employed to the system， and its time-domain responses are recorded using an LMS data acquisition system. The acquired time-domain signals are subsequently transformed into the frequency domain via Fast Fourier Transform (FFT)， thereby facilitating clearer observation and more detailed analysis of internal resonance characteristics. [Results] Focusing specifically on the 2:1 internal resonance， the following key experimental observations are made: 1) Sweep-frequency testing reveals that the low-frequency cantilever beam， with a linear natural frequency of approximately 17.5?Hz， displays distinct amplitude peaks when excited within the 48–55?Hz range; 2) Corresponding frequency-spectrum analysis indicates that under 48?Hz excitation， the response frequency of the low-frequency beam stabilizes near 24?Hz， confirming a 2:1 internal resonance between the two structural modes; 3) When the excitation frequency is tuned to about 50?Hz， the system does not initially exhibit internal resonance under steady conditions; however， introducing an external perturbation reliably triggers a pronounced 2:1 resonant response， demonstrating the sensitive dependence of the phenomenon on initial conditions and external excitations. These results collectively illustrate the characteristic frequency-coupling behavior and activation threshold associated with 2:1 internal resonance in the magnetically coupled cantilever system. [Conclusions] Practical teaching experience and implementation results confirm that the proposed experimental platform is straightforward to assemble， employs well-standardized procedures， and demonstrates high practicality and ease of use in instructional settings. Furthermore， the platform has been shown to significantly enhance students’ grasp of fundamental nonlinear-dynamics concepts and to foster their integrated development in scientific inquiry， engineering insight， and hands-on experimental competency， thereby supporting a more inquiry-driven and applied pedagogy.
Thoughts and Discussions on the Construction of Provincial Laboratories
CHEN Jie;TAN Yue;GUO Yangxue;[Objective] Provincial laboratories represent the highest-level scientific research and innovation platforms at the provincial level. They focus on national strategic objectives and major regional industrial and technological innovation needs， integrating superior scientific and technological innovation resources， achieving breakthroughs in leading and disruptive core technologies， driving the transformation and industrialization of scientific achievements， and supporting high-quality economic and social development in the region.With the steady advancement of construction， provincial laboratories have gradually shifted from a phase of rapid quantitative growth to a phase of qualitative improvement.It is necessary to address the question of how to build and develop the laboratories well after getting them established.Further in-depth thinking and research are required on their development orientation， institutional mechanisms， operation modes， evaluation methods and other related aspects.[Methods] Based on the method of policy text analysis， this study sorts out and summarizes the characteristics of provincial laboratories from four perspectives: policy and institutional guarantee， positioning of new-type institutions， innovating in systems and mechanisms， and strengthening diversified investment. Taking the construction practices of the Shaanxi Aerospace Power Laboratory and the Shaanxi Energy Laboratory as case studies， this study summarizes their construction characteristics and effectiveness in aspects such as achievement transformation， financial support， open sharing， and diversified investment through field investigations and in-depth interviews.[Results and Conclusions]Based on the current situation of Shaanxi provincial laboratories， this study proposes paths and recommendations for their transition from rapid quantitative growth in construction to sustained qualitative improvement， focusing on the following four aspects: 1) accurately defining the positioning of provincial laboratories and refining a differentiated development path distinct from other platforms and bases. On the one hand， they should target national major strategic needs， conduct forward-looking， leading-edge and innovative research， and enhance the capacity for original innovation. On the other hand， they need to closely focus on local economic development needs， select and prioritize flagship development directions and priorities， 2) encouraging innovation， and streamlining various systems and mechanisms， including the operation of independent legal entities， cooperation among directors， transformation of research achievements and mechanisms for tolerance of mistakes and trial-and-error practices， which involve establishing scientific research entities with clear responsibilities， rights and interests， independent overall allocation， and standardized management and operation; properly handling the relationships between leading units and co-constructing units such as profit distribution and the ownership of intellectual property rights; and exploring and adopting models such as "investment before equity" and "payment after use"， 3) exploring and refining the development model of integrated convergence among universities， enterprises and research institutes， as well as the model of full-chain connectivity from basic research to industrial application， so as to promote provincial laboratories to improve their operational mechanisms characterized by multi-stakeholder collaboration， integration of all factors， full-chain connectivity and all-round support; 4)adhering to a results-oriented approach， establishing an evaluation mechanism aligned with the research characteristics and operational rules of the provincial laboratories， exploring and establishing a phased and long-term performance evaluation system through the combined approach of annual reporting and regular assessment， and setting distinct evaluation indicators for the initial construction phase and operational phase respectively.
Development and Application of an Experimental Device for Lost-Circulation Plugging in Stress-Sensitive Fractures
HU Han;FENG Yongcun;LAI Chenxi;WANG Guangyu;LI Xiaorong;[Objective] Stress-sensitive fractures may undergo continuous aperture variation under wellbore pressure fluctuations during drilling. However， many existing lost-circulation evaluation methods and material-selection criteria are established under a fixed fracture aperture assumption. Therefore， the selected plugging formulations may not match the evolving fracture width， leading to plugging-layer instability and repeated loss. To address this challenge， we have developed an experimental device that represents a coupled wellbore-formation-fracture plugging system. [Methods] The device consists of a drilling-fluid circulation system， a temperature-control system， a plugging-slurry preparation system， a dynamic fracture-aperture regulation system， and a data acquisition system. It was developed to simulate lost circulation in stress-sensitive fractures with pressure-driven aperture evolution which enables independent control of fracture closure pressure， fracture-inlet pressure， temperature， and different fracture geometries. Pressure， temperature， and fracture deformation can be recorded synchronously， and loss volume can be quantified. After each test， the fracture module can be disassembled for direct observation of plugging-layer distribution and local bridging morphology. Two plugging formula systems were compared using the developed device. A conventional bridging system composed of rigid bridging and filling materials， and an elastic particle enhanced system using recycle tire rubber particles were investigated to improve deformation adaptability under dynamic conditions. The effects of fracture closure pressure， total lost circulation materials (LCM) concentration， plugging-material system， and composite plugging formula performance were systematically tested. [Results] The comparative tests indicate that increasing fracture closure pressure can improve plugging stability against dynamic aperture growth， but the improvement is only 7.5% when the closure pressure increases from 1 MPa to 3 MPa， indicating that fracture closure pressure alone has limited ability to improve dynamic plugging stability. Total LCM concentration exhibits an effective operating window. When the concentration is too low， persistent leakage occurs because a continuous and stable bridging skeleton cannot be established. When the concentration is too high， premature entrance plugging may occur， which increases the apparent pressure-bearing capacity but may result in operational risks in circulation control. The effect of elastic particles is strongly dependent on fracture aperture. In 1 mm fractures， the elastic particle enhanced system failed to form a stable pressure-bearing plugging layer， indicating that small-aperture fractures rely primarily on the rapid establishment of a stiff bridging skeleton. In 2 mm fractures， the elastic particle enhanced system reduced fluid loss from 188 mL to 133 mL under comparable conditions. This result demonstrates that elastic particles are more effective in larger fractures， where deformable filling and contact reconfiguration improve loss control. After further optimization of the rubber particle size combination， the fluid loss was reduced from 133 mL to 98 mL， while the pressure-bearing capacity remained within 4.5-4.8 MPa. This indicates that particle-size recombination mainly improves loss control and plugging-layer densification rather than markedly increasing the ultimate pressure-bearing strength. [Conclusions] The present study establishes a dedicated experimental basis for evaluating pressure-bearing plugging in stress-sensitive fractures. The coupled wellbore-formation-fracture plugging device makes it possible to link macroscopic plugging performance with the evolution of plugging-layer morphology during dynamic fracture deformation. The experimental results provide a reliable basis for dynamic plugging evaluation， mechanism-oriented formulation design， and the development of pressure-bearing plugging strategies for fractured formations.
Experimental Platform for Performance Testing of Exoskeleton Joint Motors based on ZYNQ clip
ZHU Chunxiang;DUAN Yuxiang;ZHOU Xingkai;QI Jialong;WANG Binrui;[Objective] Exoskeleton joint motors used in exoskeleton robots are required to operate under complex working conditions such as variable loads， frequent start–stop motions， and external disturbances， which place high demands on their dynamic control performance and response capability. However， existing motor performance test systems are mostly based on discrete hardware architectures and external data acquisition devices， resulting in low integration levels， limited real-time performance， and difficulties in multi-parameter synchronous measurement. To address these problems， this paper aims to design a highly integrated and real-time experimental platform for performance testing of exoskeleton joint motors based on a ZYNQ heterogeneous system， enabling accurate evaluation of both steady-state and dynamic performance indicators. [Methods] An exoskeleton joint motor performance test platform based on the ZYNQ-7010 system-on-chip is developed using a hardware–software co-design approach. The ARM processing system is responsible for test management， parameter configuration， communication， and data processing， while the programmable logic implements high-speed synchronous acquisition of torque and speed frequency signals， analog signal sampling， and dynamic load signal generation. A drag-type experimental structure is constructed by coaxially coupling the tested exoskeleton joint motor and the load motor through a torque sensor， allowing simulation of typical operating conditions encountered in exoskeleton applications. An equal-precision frequency measurement algorithm is implemented in programmable logic to ensure accurate frequency acquisition over a wide dynamic range. Meanwhile， a direct digital synthesis–based method is adopted to generate controllable and repeatable dynamic loading signals. Based on relevant national standards， experimental procedures are established to evaluate torque ripple coefficient， speed ripple coefficient， control accuracy， and step response time.[Results]The experimental results demonstrate that:1）An embedded measurement and control hardware system based on the ZYNQ-7010 is designed and implemented， integrating high-precision frequency signal acquisition interfaces with a measurement range from 1 Hz to 1 MHz， analog signal acquisition modules， and dynamic load simulation output modules;2）A drag-type physical test platform for exoskeleton joint motors is constructed， which can simulate various typical load conditions encountered during actual motion processes and supports coordinated multi-parameter testing;3）Based on a hardware–software co-design approach and in accordance with relevant national and industry standards for exoskeleton joint motor performance testing， platform-level implementation and experimental verification are carried out for key performance indicators， including torque ripple coefficient， speed ripple coefficient， control accuracy， and step response time， with data update periods ranging from 1 ms to 500 ms.
Research on visual distance measurement system for overhead transmission lines based on improved SGBM algorithm
Liu Xiuting;Gao Feng;[Objective] The overhead transmission lines are the main channels for power transmission and a critical guarantee for residents' daily lives and industrial production， widely distributed across major roads in cities， districts， counties， and towns nationwide. The municipal engineering construction was an important initiative to promote urban development and improve people's quality of life， characterized by a large number of engineering projects， large scales， and the frequent employment of engineering construction machinery. For the purpose of preventing the external damage to overhead power transmission lines and ensure the operational safety of engineering construction machinery and relevant workers， it is very necessary to develop a binocular vision ranging-based safety warning system for overhead transmission lines targeting construction machinery. [Methods] In hardware modules， the developed safety warning system mainly consists of a perception layer， a computation layer， and an application layer. In which， the perception layer includes the CMOS binocular cameras for real-time cable image acquisition and the Raspberry Pi modules for low-latency local area network (LAN) image transmission; and the computation layer includes mainly a host computer for in-depth image processing efficiently; and the application layer includes mainly the voice chips for prompts， the electromagnetic buzzer control， the LED beads， and a power supply module. In addition， the key software modules were selected seriously and improved to improve the operational performance of safety waring system effectively in realistic conditions. For example， the Zhang's calibration method recognized by numerous scholars was taken into consideration for 3D calibration effectively， and the Bouguet rectification method considered widely was also employed for the epipolar rectification and the improvement of image distortion effectively. Specifically， an improved semi global block matching (SGBM) algorithm was proposed and used to enhance the stereo matching performance. In which， the adaptive windows， the noise tolerance variables， and the RGB channel absolute color difference (ACD) costs were introduced simultaneous into the traditional CT (Census Transform) method to obtain an improved cost calculation approach; and then， a four-path cost aggregation strategy was carried out for the initial matching cost aggregation; next， the Winner-Take-All (WTA) algorithm was used to solve the initial disparity of the target image; finally， the obtained initial disparity was optimized to solve the optimal disparity of target image by means of the median filtering algorithm.[Results] The testing results show that compared with the traditional SGBM algorithm， the image processing time of improved SGBM algorithm (3.528ms) increases by 18.26%， but its overall error rate (2.79%) and the non-occlusion error rate (2.16%) decrease by 95.08% and 95.04% respectively; meanwhile， the relative error between the detected values of the binocular vision-based overhead transmission line ranging system and the actual distances was consistently maintained within the range of 0.691% to 2.482%.[Conclusions] In a word， the binocular vision-based overhead transmission line ranging system developed in this research exhibits the high measurement accuracy， the high detection efficiency， and the good operational stability in realistic condition， which can ensure the working operation safety of engineering construction machinery effectively and prevent the external damage to overhead power transmission lines obviously.
Development and Application of an Integrated GTAW and GMAW Arc Additive Manufacturing Experimental Platform
LI Yongcun;LIU Zeguo;ZHANG Jiabao;WANG Yong;[Objective] Wire Arc Additive Manufacturing (WAAM) acts as a pivotal technology within the "Made in China 2025" strategy， distinguished by its superior deposition efficiency and material utilization compared to laser or electron beam-based additive manufacturing methods. Despite its industrial potential for manufacturing medium-to-large metal components， the widespread adoption of WAAM in academic research and small-to-medium enterprises is currently constrained by the prohibitive costs and closed-source architectures of commercial systems. Conversely， existing low-cost open-source platforms often fail to meet necessary standards for motion control precision， forming stability， and system extensibility， particularly regarding the integration of multiple welding processes. To bridge this gap， this study aims to design and construct a cost-effective， desktop-level experimental platform that integrates both Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes using an open-source control architecture， thereby providing a robust tool for process validation and engineering education.[Methods] The experimental platform was developed using a modular， open-source architecture featuring a moving gantry three-axis mechanical structure. To optimize cost and spatial efficiency， both GTAW and GMAW torches were integrated onto the Z-axis. High-torque 86×80 stepper motors (4.5 N·m) driven by high-subdivision drivers and ball screw transmission were selected to ensure positioning precision and structural rigidity. The control system adopts a master-slave configuration where a PC generates G-code trajectories and an Arduino Uno running Grbl firmware executes real-time motion control， synchronizing arc ignition/extinction (M8/M9 commands) and gas supply via relay modules. To mitigate oxidation in local shielding， a novel dual-path gas system was designed， combining standard torch delivery with a bottom micro-pore supply embedded in the fixture. Single-bead deposition experiments using Q345B steel substrates and ER50-6 wire were conducted to systematically investigate the effects of travel speed (0.24–0.48 m/min) and wire feed speed (5-7 m/min) on bead geometry and forming quality.[Results] Experimental analysis revealed a distinct linear correlation between process parameters and bead geometry. Specifically， increasing the wire feed speed from 5.0 to 7.0 m/min significantly expanded the bead width from 3.889 mm to 6.115 mm and increased reinforcement from 1.252 mm to 4.029 mm， driven by the higher deposition rate. However， excessive wire feed speed (7.0 m/min) compromised stability， causing severe spatter and undercutting， while excessive travel speed led to snake-like defects and discontinuity. The optimal parameter combination was identified as a travel speed of 0.36 m/min and a wire feed speed of 6 m/min. This setting achieved a dilution rate between 5% and 15% and facilitated the fabrication of complex structures like single-bead multi-layer walls without macroscopic defects. Microstructural analysis confirmed a matrix of proeutectoid ferrite， acicular ferrite， bainite， and pearlite. Notably， regional variations were observed: the bottom zone featured coarse grains due to substrate quenching; the middle zone formed interlaced acicular ferrite under moderate cooling; and the top zone contained side-plate ferrite and pearlite induced by solute enrichment.[Conclusions] The developed platform successfully integrates GTAW and GMAW processes within a low-cost， open-source framework， achieving a balance between cost-effectiveness and high control precision. By enabling the fabrication of well-formed metal components with sound microstructures， the platform proves its viability as a versatile and economical solution for WAAM process exploration， teaching demonstrations， and fundamental research in universities and research institutions.