Robotica最新文献

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Control of stance-leg motion and zero-moment point for achieving perfect upright stationary state of rimless wheel type walker with parallel linkage legs 控制平行联动腿的无轮辋轮式助行器的姿态腿运动和零时刻点,以实现完美的直立静止状态
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-19 DOI: 10.1017/s0263574724001292
Fumihiko Asano, Mizuki Kawai
{"title":"Control of stance-leg motion and zero-moment point for achieving perfect upright stationary state of rimless wheel type walker with parallel linkage legs","authors":"Fumihiko Asano, Mizuki Kawai","doi":"10.1017/s0263574724001292","DOIUrl":"https://doi.org/10.1017/s0263574724001292","url":null,"abstract":"The authors have studied models and control methods for legged robots without having active ankle joints that can not only walk efficiently but also stop and developed a method for generating a gait that starts from an upright stationary state and returns to the same state in one step for a simple walker with one control input. It was clarified, however, that achieving a perfect upright stationary state including zero dynamics is impossible. Based on the observation, in this paper we propose a novel robotic walker with parallel linkage legs that can return to a perfect stationary standing posture in one step while simultaneously controlling the stance-leg motion and zero-moment point (ZMP) using two control inputs. First, we introduce a model of a planar walker that consists of two eight-legged rimless wheels, a body frame, a reaction wheel, and massless rods and describe the system dynamics. Second, we consider two target control conditions; one is control of the stance-leg motion, and the other is control of the ZMP to stabilize zero dynamics. We then determine the control input based on the two conditions with the target control period derived from the linearized model and consider adding a sinusoidal control input with an offset to correct the resultant terminal state of the reaction wheel. The validity of the proposed method is investigated through numerical simulations.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"75 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Trajectory tracking control of a mobile robot using fuzzy logic controller with optimal parameters 使用具有最佳参数的模糊逻辑控制器对移动机器人进行轨迹跟踪控制
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-19 DOI: 10.1017/s0263574724001140
Tesfaye Deme Tolossa, Manavaalan Gunasekaran, Kaushik Halder, Hitendra Kumar Verma, Shyam Sundar Parswal, Nishant Jorwal, Felix Orlando Maria Joseph, Yogesh Vijay Hote
{"title":"Trajectory tracking control of a mobile robot using fuzzy logic controller with optimal parameters","authors":"Tesfaye Deme Tolossa, Manavaalan Gunasekaran, Kaushik Halder, Hitendra Kumar Verma, Shyam Sundar Parswal, Nishant Jorwal, Felix Orlando Maria Joseph, Yogesh Vijay Hote","doi":"10.1017/s0263574724001140","DOIUrl":"https://doi.org/10.1017/s0263574724001140","url":null,"abstract":"This work investigates the use of a fuzzy logic controller (FLC) for two-wheeled differential drive mobile robot trajectory tracking control. Due to the inherent complexity associated with tuning the membership functions of an FLC, this work employs a particle swarm optimization algorithm to optimize the parameters of these functions. In order to automate and reduce the number of rule bases, the genetic algorithm is also employed for this study. The effectiveness of the proposed approach is validated through MATLAB simulations involving diverse path tracking scenarios. The performance of the FLC is compared against established controllers, including minimum norm solution, closed-loop inverse kinematics, and Jacobian transpose-based controllers. The results demonstrate that the FLC offers accurate trajectory tracking with reduced root mean square error and controller effort. An experimental, hardware-based investigation is also performed for further verification of the proposed system. In addition, the simulation is conducted for various paths in the presence of noise in order to assess the proposed controller’s robustness. The proposed method is resilient against noise and disturbances, according to the simulation outcomes.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"33 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
High accuracy hybrid kinematic modeling for serial robotic manipulators 串行机器人机械手的高精度混合运动学建模
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-19 DOI: 10.1017/s026357472400136x
Marco Ojer, Ander Etxezarreta, Gorka Kortaberria, Brahim Ahmed, Jon Flores, Javier Hernandez, Elena Lazkano, Xiao Lin
{"title":"High accuracy hybrid kinematic modeling for serial robotic manipulators","authors":"Marco Ojer, Ander Etxezarreta, Gorka Kortaberria, Brahim Ahmed, Jon Flores, Javier Hernandez, Elena Lazkano, Xiao Lin","doi":"10.1017/s026357472400136x","DOIUrl":"https://doi.org/10.1017/s026357472400136x","url":null,"abstract":"In this study, we present a hybrid kinematic modeling approach for serial robotic manipulators, which offers improved accuracy compared to conventional methods. Our method integrates the geometric properties of the robot with ground truth data, resulting in enhanced modeling precision. The proposed forward kinematic model combines classical kinematic modeling techniques with neural networks trained on accurate ground truth data. This fusion enables us to minimize modeling errors effectively. In order to address the inverse kinematic problem, we utilize the forward hybrid model as feedback within a non-linear optimization process. Unlike previous works, our formulation incorporates the rotational component of the end effector, which is beneficial for applications involving orientation, such as inspection tasks. Furthermore, our inverse kinematic strategy can handle multiple possible solutions. Through our research, we demonstrate the effectiveness of the hybrid models as a high-accuracy kinematic modeling strategy, surpassing the performance of traditional physical models in terms of positioning accuracy.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"45 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An application of natural matrices to the dynamic balance problem of planar parallel manipulators 自然矩阵在平面平行机械手动态平衡问题中的应用
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-19 DOI: 10.1017/s0263574724001267
Jaime Gallardo-Alvarado
{"title":"An application of natural matrices to the dynamic balance problem of planar parallel manipulators","authors":"Jaime Gallardo-Alvarado","doi":"10.1017/s0263574724001267","DOIUrl":"https://doi.org/10.1017/s0263574724001267","url":null,"abstract":"This paper introduces a simplified matrix method for balancing forces and moments in planar parallel manipulators. The method resorts to Newton’s second law and the concept of angular momentum vector, yet it is not necessary to perform the velocity and acceleration analyses, tasks that were normally unavoidable in seminal contributions. With the introduction of natural matrices, the proposed balancing method is independent of the time and the trajectory generated by the moving links of parallel manipulators. The effectiveness of the method is exemplified by balancing two planar parallel manipulators.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"23 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
3D dynamics and control of a snake robot in uncertain underwater environment 不确定水下环境中蛇形机器人的三维动力学与控制
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-19 DOI: 10.1017/s0263574724000821
Bhavik M. Patel, Santosha K. Dwivedy
{"title":"3D dynamics and control of a snake robot in uncertain underwater environment","authors":"Bhavik M. Patel, Santosha K. Dwivedy","doi":"10.1017/s0263574724000821","DOIUrl":"https://doi.org/10.1017/s0263574724000821","url":null,"abstract":"<p>The snake robot can be used to monitor and maintain underwater structures and environments. The motion of a snake robot is achieved by lateral undulation which is called the gait pattern of the snake robot. The parameters of a gait pattern need to be adjusted for compensating environmental uncertainties. In this work, 3D motion dynamics of a snake robot for the underwater environment is proposed with vertical motion using the buoyancy variation technique and horizontal motion using lateral undulation. “The neutral buoyant snake robot motion in hypothetical plane and added mass effect is negligible”, these previous assumptions are removed in this work. Two different control algorithms are designed for horizontal and vertical motions. The existing super twisting sliding mode control (STSMC) is used for the horizontal serpentine motion of the snake robot. The control law is designed on a reduced-ordered dynamic system based on virtual holonomic constraints. The vertical motion is achieved by controlling the mass variation using a pump. The water pumps are controlled using the event-based controller or Proportional Derivative (PD) controller. The results of the proposed control technique are verified with various external environmental disturbances and uncertainties to check the robustness of the control approach for various path following cases. Moreover, the results of STSMC scheme are compared with SMC scheme to check the effectiveness of STSMC. The practical implementation of the work is also performed using Simscape Multibody environment where the designed control algorithm is deployed on the virtual snake robot.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"44 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Artificial neural network-based control of powered knee exoskeletons for lifting tasks: design and experimental validation 基于人工神经网络的动力膝关节外骨骼起重任务控制:设计与实验验证
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-18 DOI: 10.1017/s0263574724001206
Asif Arefeen, Yujiang Xiang
{"title":"Artificial neural network-based control of powered knee exoskeletons for lifting tasks: design and experimental validation","authors":"Asif Arefeen, Yujiang Xiang","doi":"10.1017/s0263574724001206","DOIUrl":"https://doi.org/10.1017/s0263574724001206","url":null,"abstract":"This study introduces a hybrid model that utilizes a model-based optimization method to generate training data and an artificial neural network (ANN)-based learning method to offer real-time exoskeleton support in lifting activities. For the model-based optimization method, the torque of the knee exoskeleton and the optimal lifting motion are predicted utilizing a two-dimensional (2D) human–exoskeleton model. The control points for exoskeleton motor current profiles and human joint angle profiles from cubic B-spline interpolation represent the design variables. Minimizing the square of the normalized human joint torque is considered as the cost function. Subsequently, the lifting optimization problem is tackled using a sequential quadratic programming (SQP) algorithm in sparse nonlinear optimizer (SNOPT). For the learning-based approach, the learning-based control model is trained using the general regression neural network (GRNN). The anthropometric parameters of the human subjects and lifting boundary postures are used as input parameters, while the control points for exoskeleton torque are treated as output parameters. Once trained, the learning-based control model can provide exoskeleton assistive torque in real time for lifting tasks. Two test subjects’ joint angles and ground reaction forces (GRFs) comparisons are presented between the experimental and simulation results. Furthermore, the utilization of exoskeletons significantly reduces activations of the four knee extensor and flexor muscles compared to lifting without the exoskeletons for both subjects. Overall, the learning-based control method can generate assistive torque profiles in real time and faster than the model-based optimal control approach.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"196 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Obstacle avoidance control of UGV based on adaptive-dynamic control barrier function in unstructured terrain 基于自适应动态控制障碍函数的 UGV 在非结构化地形中的避障控制
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-18 DOI: 10.1017/s026357472400122x
Liang Guo, Suyu Zhang, Wenlong Zhao, Jun Liu, Ruijun Liu
{"title":"Obstacle avoidance control of UGV based on adaptive-dynamic control barrier function in unstructured terrain","authors":"Liang Guo, Suyu Zhang, Wenlong Zhao, Jun Liu, Ruijun Liu","doi":"10.1017/s026357472400122x","DOIUrl":"https://doi.org/10.1017/s026357472400122x","url":null,"abstract":"The widely used model predictive control of discrete-time control barrier functions (MPC-CBF) has difficulties in obstacle avoidance for unmanned ground vehicles (UGVs) in complex terrain. To address this problem, we propose adaptive dynamic control barrier functions (AD-CBF). AD-CBF is able to adaptively select an extended class of functions of CBF to optimize the feasibility and flexibility of obstacle avoidance behaviors based on the relative positions of the UGV and the obstacle, which in turn improves the obstacle avoidance speed and safety of the MPC algorithm when integrated with MPC. The algorithmic constraints of the CBF employ hierarchical density-based spatial clustering of applications with noise (HDBSCAN) for parameterization of dynamic obstacle information and unscaled Kalman filter (UKF) for trajectory prediction. Through simulations and practical experiments, we demonstrate the effectiveness of the AD-CBF-MPC algorithm in planning optimal obstacle avoidance paths in dynamic environments, overcoming the limitations of the point-by-point feasibility of MPC-CBF.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"26 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Artificial neural network-based model predictive visual servoing for mobile robots 基于人工神经网络的移动机器人视觉伺服预测模型
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-18 DOI: 10.1017/s0263574724001176
Seong Hyeon Hong, Benjamin Albia, Tristan Kyzer, Jackson Cornelius, Eric R. Mark, Asha J. Hall, Yi Wang
{"title":"Artificial neural network-based model predictive visual servoing for mobile robots","authors":"Seong Hyeon Hong, Benjamin Albia, Tristan Kyzer, Jackson Cornelius, Eric R. Mark, Asha J. Hall, Yi Wang","doi":"10.1017/s0263574724001176","DOIUrl":"https://doi.org/10.1017/s0263574724001176","url":null,"abstract":"This paper presents an artificial neural network (ANN)-based nonlinear model predictive visual servoing method for mobile robots. The ANN model is developed for state predictions to mitigate the unknown dynamics and parameter uncertainty issues of the physics-based (PB) model. To enhance both the model generalization and accuracy for control, a two-stage ANN training process is proposed. In a pretraining stage, highly diversified data accommodating broad operating ranges is generated by a PB kinematics model and used to train an ANN model first. In the second stage, the test data collected from the actual system, which is limited in both the diversity and the volume, are employed to further finetune the ANN weights. Path-following experiments are conducted to compare the effects of various ANN models on nonlinear model predictive control and visual servoing performance. The results confirm that the pretraining stage is necessary for improving model generalization. Without pretraining (i.e., model trained only with the test data), the robot fails to follow the entire track. Weight finetuning with the captured data further improves the tracking accuracy by 0.07–0.15 cm on average.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"9 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimal robot task scheduling in cluttered environments considering mechanical advantage 考虑机械优势,在杂乱环境中优化机器人任务调度
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-18 DOI: 10.1017/s0263574724001371
Paraskevi Th. Zacharia, Elias K. Xidias
{"title":"Optimal robot task scheduling in cluttered environments considering mechanical advantage","authors":"Paraskevi Th. Zacharia, Elias K. Xidias","doi":"10.1017/s0263574724001371","DOIUrl":"https://doi.org/10.1017/s0263574724001371","url":null,"abstract":"In various industrial robotic applications, the effective traversal of a manipulator amidst obstacles and its ability to reach specific task-points are imperative for the execution of predefined tasks. In certain scenarios, the sequence in which the manipulator reaches these task-points significantly impacts the overall cycle time required for task completion. Moreover, some tasks necessitate significant force exertion at the end-effector. Therefore, establishing an optimal sequence for the task-points reached by the end-effector’s tip is crucial for enhancing robot performance, ensuring collision-free motion and maintaining high-force application at the end-effector’s tip. To maximize the manipulator’s manipulability, which serves as a performance index for assessing its force capability, we aim to establish an optimal collision-free task sequence considering higher mechanical advantage. Three optimization criteria are considered: the cycle time, collision avoidance and the manipulability index. Optimization is accomplished using a genetic algorithm coupled with the Bump-Surface concept for collision avoidance. The effectiveness of this approach is confirmed through simulation experiments conducted in 2D and 3D environments with obstacles employing both redundant and non-redundant robots.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"54 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Robust motion planning for mobile robots under attacks against obstacle localization 移动机器人在障碍物定位攻击下的鲁棒运动规划
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-18 DOI: 10.1017/s0263574724001115
Fenghua Wu, Wenbing Tang, Yuan Zhou, Shang-Wei Lin, Zuohua Ding, Yang Liu
{"title":"Robust motion planning for mobile robots under attacks against obstacle localization","authors":"Fenghua Wu, Wenbing Tang, Yuan Zhou, Shang-Wei Lin, Zuohua Ding, Yang Liu","doi":"10.1017/s0263574724001115","DOIUrl":"https://doi.org/10.1017/s0263574724001115","url":null,"abstract":"Thanks to its real-time computation efficiency, deep reinforcement learning (DRL) has been widely applied in motion planning for mobile robots. In DRL-based methods, a DRL model computes an action for a robot based on the states of its surrounding obstacles, including other robots that may communicate with it. These methods always assume that the environment is attack-free and the obtained obstacles’ states are reliable. However, in the real world, a robot may suffer from obstacle localization attacks (OLAs), such as sensor attacks, communication attacks, and remote-control attacks, which cause the robot to retrieve inaccurate positions of the surrounding obstacles. In this paper, we propose a robust motion planning method <jats:monospace>ObsGAN-DRL</jats:monospace>, integrating a generative adversarial network (GAN) into DRL models to mitigate OLAs in the environment. First, <jats:monospace>ObsGAN-DRL</jats:monospace> learns a generator based on the GAN model to compute the approximation of obstacles’ accurate positions in benign and attack scenarios. Therefore, no detectors are required for <jats:monospace>ObsGAN-DRL</jats:monospace>. Second, by using the approximation positions of the surrounding obstacles, <jats:monospace>ObsGAN-DRL</jats:monospace> can leverage the state-of-the-art DRL methods to compute collision-free motion commands (e.g., velocity) efficiently. Comprehensive experiments show that <jats:monospace>ObsGAN-DRL</jats:monospace> can mitigate OLAs effectively and guarantee safety. We also demonstrate the generalization of <jats:monospace>ObsGAN-DRL</jats:monospace>.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"11 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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