NetWork
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.
Experimental Study on Dynamic Performance of Tunnel Damping Measures Considering Initial Support
QI Bing;XU Haibin;JIANG Chenchen;ZHANG Guangkui;WEI Hong;MA Zhigang;[Objective] Tunnels in high-intensity seismic regions are prone to severe earthquake-induced damage， such as lining cracking， spalling， invert uplift， and progressive plastic deformation， which threaten structural safety and serviceability. Although seismic isolation layers have been widely applied to mitigate tunnel seismic responses， most existing studies focus on the interaction between the secondary lining and isolation layer， while the role of primary support—an essential component in practical tunnel construction—has rarely been explicitly considered. This study aims to clarify the dynamic response characteristics and damage evolution of tunnel linings when seismic mitigation measures are implemented under realistic primary-support conditions. By incorporating primary support into the mitigation system， the effectiveness of a composite “secondary lining-seismic isolation layer-primary support-surrounding rock” configuration is experimentally evaluated， providing guidance for resilience-oriented tunnel seismic design. [Methods] The Jiedexiu No. 2 Tunnel on the Lasa–Linzhi Railway was selected as a representative case， and a series of shaking-table model tests were conducted. A gravity-distorted similarity model was designed based on the Buckingham π theorem， with a geometric similarity ratio of 1:40 and appropriate scaling of elastic modulus， density， displacement， and acceleration. The surrounding rock and overburden were simulated to represent Grade V phyllite and gravelly-breccia soils， respectively. The secondary lining was modeled using gypsum to simulate C30 concrete， while a sponge rubber material was adopted as the seismic isolation layer. Basalt fiber-reinforced polymer anchors were employed to simulate rock bolts in the primary support. Horizontal excitation was applied using the EL Centro earthquake wave with peak ground accelerations of 0.1 g， 0.2 g， 0.3 g， and 0.4 g. Acceleration sensors and strain gauges were symmetrically arranged to compare a conventional section and a mitigated section incorporating the isolation layer and primary support. Dynamic responses were analyzed in both time and frequency domains， including acceleration time histories， Fourier spectra， and acceleration response spectra. To quantify cumulative damage， a Plastic Deformation Index (PDI)， defined as the ratio of residual strain to peak dynamic strain， was introduced to classify damage evolution into elastic， elasto-plastic， and plastic stages. [Results] The results show that the seismic isolation layer significantly reduces the peak amplitudes of acceleration response spectra and Fourier spectra without altering their overall spectral shape. Under low-intensity excitation (0.1 g)， the response spectra exhibit multi-peak characteristics with a predominant period of approximately 0.06 s. With increasing ground-motion intensity， the spectra gradually evolve into a single-peak pattern， accompanied by a lengthening of the predominant period to about 0.08 s， indicating enhanced system nonlinearity and amplification of low-frequency components. Dynamic strain measurements reveal that the mitigated section consistently experiences lower strain peaks and slower strain accumulation， particularly at the crown and invert. In contrast， the haunch exhibits the weakest mitigation effect due to strong boundary constraints. PDI analysis indicates that the conventional section enters a plastic-dominated state when excitation exceeds 0.3 g， whereas the mitigated section remains predominantly in the elasto-plastic stage with substantially lower PDI values. Post-test observations confirm that damage in the mitigated section is markedly reduced compared with the conventional section. [Conclusions] The experimental results demonstrate that a seismic mitigation configuration explicitly considering primary support and incorporating a seismic isolation layer can effectively improve tunnel seismic performance under high-intensity earthquake loading. The composite system reduces spectral amplitudes and plastic deformation demand while preserving the fundamental spectral characteristics of the lining response. The mitigation effect is most pronounced at the invert and crown， whereas the haunch remains a critical zone requiring enhanced design attention. The proposed approach provides a practical experimental basis for energy-dissipation-oriented seismic design and retrofit of tunnels in earthquake-prone regions.
Study on the road performance of basalt fiber reinforced asphalt mixture by test and discrete element simulation
Wu Kun;HE Wanping;Xiong Liwei;Ma Jie;Chen Yu;Huang Xin;Li Changhui;Qi Lin;Sun Bowei;Erwin Oh;Asphalt mixture is a widely used pavement material in road engineering and airport engineering， and fibers can significantly enhance its road performance. However， research on the uniaxial compressive performance of fiber-reinforced asphalt mixtures and the microscopic enhancement mechanism of fibers remains limited. The basalt fiber reinforced asphalt mixture is taken as the research object. The basalt fiber reinforced asphalt mixture material tests， such as Marshall test and uniaxial compressive tests， are carried out to study the effect of basalt fiber content on the physical and mechanical properties of asphalt mixture， such as bulk density， stability， flow value， and compressive strength. Based on the discrete element simulation， a numerical model for basalt fiber reinforced asphalt mixture is established， where the fibers are modeled as clumps， aggregates with diameter larger than 2.36 mm are represented as balls， and the asphalt mortar， composed of aggregates smaller than 2.36 mm and base asphalt， is simulated using a contact model. The discrete element model is verified with the test results and the contact parameters are calibrated. The whole process of crack formation， development and failure of asphalt mixture under uniaxial compression is studied. The results show that (1) With the increase of fiber content， the bulk density and voids filled with asphalt gradually decrease， the void content of asphalt mixture， the optimum asphalt binder content and mineral aggregate voidage of asphalt mixture increase; (2) the incorporation of basalt fibers significantly enhances the mechanical properties of asphalt mixtures， including Marshall stability， flow value， and compressive strength. Compared to asphalt mixtures without fiber， the uniaxial compressive strength increased by 13.2%， 43.3%， and 8.3% at fiber content of 0.2%， 0.3%， and 0.4% by weight， respectively; (3) Fiber content significantly influences the axial compressive performance of asphalt mixtures. The peak value of compressive strength arises at 0.3% fiber content for the asphalt mixtures in the study. When the basalt fiber content is below 0.6%， the compressive strength initially increases then decreases with rising fiber content， yet remains higher than that of mixtures without fiber. Conversely， when fiber content exceeds 0.6%， the compressive strength falls below that of mixtures without fibers; (4) The discrete element model of basalt fiber reinforced asphalt mixtures established accurately simulates the uniaxial compression process. Microstructural analysis reveals that with increasing basalt fiber content， edge fragmentation phenomena and crack propagation in asphalt mixture specimens are significantly reduced， while the number of interparticle contacts markedly increases. Analysis indicates that the discrete element model of asphalt mixtures developed using discrete element modeling software can accurately simulate the internal microscopic mechanisms during uniaxial compression， revealing the influence of basalt fibers on contact evolution and crack propagation within the mixture. Adding an appropriate amount of basalt fibers can enhance the physical and mechanical properties of asphalt mixtures. However， excessive fiber content may lead to fiber aggregation phenomena， resulting in performance degradation. Therefore， for practical engineering applications， the optimal fiber dosage should be determined through experimental testing and theoretical analysis based on specific conditions. The research results have significant reference value for the design of fiber asphalt mixture pavement or airport runway.
Experimental platform for the visual display of the Pockels effect in electro-optic crystals: design and pedagogical application
WENG Yunqi;WU Jiawei;HUANG Yifan;[Objective] The Pockels effect is a foundational principle in the interdisciplinary field of optics and electromagnetism. However， existing experimental methods are incapable of directly measuring the electro-optic phase delay. These methods present several limitations， including dependence on optical power， a high threshold for experimental comprehension， and a disconnect between theoretical principles and concrete cognition. This paper proposes a visualized measurement platform for the Pockels effect that intuitively presents the dynamic variation of electro-optic phase delay under voltage modulation. The platform exhibits core performance characteristics of a wide measurement range and high linearity. The integration of simulation modeling with physical experiments in the teaching process is shown to facilitate the establishment of a concrete correlation between the electric field and phase delay for students. This approach also enhances comprehension of the Pockels effect and improves the quality and efficiency of experimental instruction. [Methods] The visualization platform for measuring the Pockels effect is based on a linear demodulation mode of electro-optic phase delay， implemented through both simulation and experimentation. The specific technical route is as follows. A laser generates linearly polarized light using a polarizer， which then passes through a BGO crystal and a quarter-wave plate. The application of an electric field modulation induces rotation of the polarization plane of the linearly polarized light. The emerging light subsequently passes through an S-wave plate and a polarizer， where the S-wave plate converts linear polarization into radial polarization. When combined with a polarizing filter， the linearly polarized light is transformed into a light and dark gradient ring. The ring rotates in response to changes in the polarization plane angle. Accordingly， real-time detection of the electro-optic phase delay is achieved by observing the rotation of the ring. An image-processing system is proposed to determine the rotation angle of the ring， incorporating image preprocessing， edge detection， and circular positioning. The rotation angle and the corresponding electro-optic phase delay are obtained by plotting the radial gray-value distribution of the ring and calculating the horizontal displacement of the gray-value characteristic curve. [Results] Simulation results show that the proposed measurement system produces a ring spot that rotates with changes in the applied voltage. The electro-optic phase delay angle is found to be twice the rotation angle of the ring. Physical experimental results demonstrate that the system can achieve a dynamic measurement range of 0 to 360° of electro-optic phase delay. The observed phase delay varies linearly with the applied modulation voltage. The measured linearity is 0.47%， with a maximum error not exceeding 1.5%. [Conclusions] This paper provides a comprehensive evaluation of the feasibility of a visual display platform for demonstrating the Pockels effect in electro-optic crystals from three perspectives: theoretical derivation， simulation modeling， and experimental verification. The use of simulation models enhances students’ understanding of the underlying principles of the Pockels effect， while the incorporation of physical experiments strengthens their practical skills. Overall， the platform transforms the abstract principle of the Pockels effect into an intuitive rotation of a light pattern， thereby establishing a direct visual connection between the electric field and phase delay and enabling students to apply theoretical knowledge more effectively.
Design of a testing scheme for power conversion efficiency in organic solar cells
WANG Shanshan;LUAN Shiqi;ZHOU Yuting;DU Jianxin;[Objective] This research addresses the critical limitations of conventional organic solar cells(OSCs) testing methodologies， which exhibit considerable inaccuracies and poor reproducibility due to shared indium tin oxide (ITO) electrodes， nonuniform light illumination， and inefficient device layouts. These issues lead to unreliable photovoltaic parameter measurements， hindering meaningful performance evaluation and industrial scalability. [Methods] To overcome these challenges， we designed an innovative testing system consisting of a multidevice ITO substrate with independent electrodes， a precision shadow mask， and a reverse back-pressure probe apparatus. This integrated approach ensures consistent probe contact， fixed illumination geometry， and minimized interdevice interference， thereby substantially improving measurement accuracy， data parallelism， and operational efficiency. Our work provides a robust， standardized testing platform essential for advancing OSCs research， optimizing materials， and accelerating the transition toward commercial applications. To elaborate， the redesigned ITO substrate features multiple discretely and uniformly distributed device units， each with independent anode and cathode electrodes to eliminate shared ITO resistance effects and interdevice interference during measurement. The corresponding shadow mask facilitates the fabrication of well-defined cathode layers via thermal evaporation. The core measurement innovation is the reverse back-pressure probe apparatus that replaces traditional manual clamping. It incorporates six independent probe sets (each with anode and cathode contacts) aligned using eight pairs of neodymium magnets for rapid， precise， and repeatable positioning. The proposed system includes calibrated alignment marks and fixed-size optical windows to ensure uniform light exposure from the solar simulator， eliminating spatial inhomogeneity errors. Each probe set contacts the electrode pads at identical distances， thereby minimizing variations in series resistance. Validation was performed using the D18:L8-BO system， comparing performance parameters (JSC， UOC， FF， and PCE) obtained from traditional linear-substrate devices and the new discrete-substrate devices. Statistical analysis of efficiency distributions and standard deviations confirmed enhanced accuracy， parallelism， and reproducibility. [Results] The novel testing system demonstrated exceptional performance improvements over conventional methods. Devices fabricated on the new ITO substrate with independent electrodes showed remarkable parameter consistency， with the PCE standard deviation reduced to 0.057% compared with 0.24% in traditional linear layouts. The reverse back-pressure probe system enabled rapid， simultaneous testing of six devices with perfect contact reproducibility， eliminating distance-dependent efficiency attenuation. Crucially， the discrete device distribution provided significant insights into the uniformity of the active layer across large areas. This integrated approach achieved breakthroughs in testing accuracy， throughput， and reliability， enabling the publication of high-efficiency OSCs research with industrial-grade validation capabilities. The proposed system design effectively resolved the issues of shared-electrode interference and illumination inhomogeneity in OSCs characterization. [Conclusions] This study successfully developed and validated an innovative testing system that fundamentally addresses long-standing challenges in OSCs characterization. By integrating a discrete-electrode substrate， precision mask， and reverse back-pressure probe apparatus， we achieved unprecedented measurement accuracy， device-to-device consistency， and operational efficiency. Furthermore， the system eliminates key error sources such as shared-electrode interference， probe-distance variability， and light inhomogeneity. This breakthrough provides a robust platform for reliable high-throughput OSCs performance evaluation， ultimately accelerating research reproducibility and bridging critical gaps toward the industrial-scale development and validation of organic photovoltaic technologies.
Simulation experiment of robot path planning based on improved VSRB-RRT algorithm
NI Jianyun;LI Hao;GU Haiqing;DU Helei;WU Jie;XUE Chenyang;To address the problems of low sampling efficiency， long and unsmooth paths， and the inability to avoid obstacles in real time in the B-RRT algorithm for path planning， this paper proposes a fusion algorithm for obstacle avoidance path planning based on improved variable sampling region bidirectional RRT (VSRB-RRT) and DWA. In the global planning process， the improved VSRB-RRT algorithm uses a combination of variable sampling region and target biasing strategy to speed up rate of convergence and improve sampling efficiency， and uses greedy optimization， iterative optimization and key point optimization to generate low-cost and smooth executable paths. In the local planning process， the path planned by the improved VSRB-RRT algorithm is used as a guide to select the key points on the path， and the improved DWA algorithm is used for segmented planning on the key point segmented path. Simulation experiments have shown that the improved VSRB-RRT algorithm has good search efficiency， can obtain the optimal path with the least time and the most stable efficiency， and also verifies the effectiveness of the fusion algorithm in real-time obstacle avoidance path planning.