Robotica最新文献

筛选
英文 中文
A study on path-planning algorithm for a multi-section continuum robot in confined multi-obstacle environments 密闭多障碍物环境中的多节连续机器人路径规划算法研究
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-16 DOI: 10.1017/s0263574724001383
Guohua Gao, Dongjian Li, Kai Liu, Yuxin Ge, Chunxu Song
{"title":"A study on path-planning algorithm for a multi-section continuum robot in confined multi-obstacle environments","authors":"Guohua Gao, Dongjian Li, Kai Liu, Yuxin Ge, Chunxu Song","doi":"10.1017/s0263574724001383","DOIUrl":"https://doi.org/10.1017/s0263574724001383","url":null,"abstract":"<p>In confined multi-obstacle environments, generating feasible paths for continuum robots is challenging due to the need to avoid obstacles while considering the kinematic limitations of the robot. This paper deals with the path-planning algorithm for continuum robots in confined multi-obstacle environments to prevent their over-deformation. By modifying the tree expansion process of the Rapidly-exploring Random Tree Star (RRT<span>*</span>) algorithm, a path-planning algorithm called the continuum-RRT<span>*</span> algorithm herein is proposed to achieve fewer iterations and faster convergence as well as generating desired paths that adhere to the kinematic limitations of the continuum robots. Then path planning and path tracking are implemented on a tendon-driven four-section continuum robot to validate the effectiveness of the path-planning algorithm. The path-planning results show that the path generated by the algorithm indeed has fewer transitions, and the path generated by the algorithm is closer to the optimal path that satisfies the kinematic limitations of the continuum robot. Furthermore, path-tracking experiments validate the successful navigation of the continuum robot along the algorithm-generated path, exhibiting an error range of 2.51%–3.91%. This attests to the effectiveness of the proposed algorithm in meeting the navigation requirements of continuum robots.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"9 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269375","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
Guaranteed real-time cooperative collision avoidance for n-DOF manipulators n-DOF 机械手的实时协同防撞保证
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-16 DOI: 10.1017/s0263574724001334
Erick J. Rodríguez-Seda, Michael D. M. Kutzer
{"title":"Guaranteed real-time cooperative collision avoidance for n-DOF manipulators","authors":"Erick J. Rodríguez-Seda, Michael D. M. Kutzer","doi":"10.1017/s0263574724001334","DOIUrl":"https://doi.org/10.1017/s0263574724001334","url":null,"abstract":"<p>This paper presents a decentralized, cooperative, real-time avoidance control strategy for robotic manipulators. The proposed avoidance control law builds on the concepts of artificial potential field functions and provides tighter bounds on the minimum safe distance when compared to traditional potential-based controllers. Moreover, the proposed avoidance control law is given in analytical, continuous closed form, avoiding the use of optimization techniques and discrete algorithms, and is rigorously proven to guarantee collision avoidance at all times. Examples of planar and 3D manipulators with cylindrical links under the proposed avoidance control are given and compared with the traditional approach of modeling links and obstacles with multiple spheres. The results show that the proposed avoidance control law can achieve, in general, faster convergence, smaller tracking errors, and lower control torques than the traditional approach. Furthermore, we provide extensions of the avoidance control to robotic manipulators with bounded control torques.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"101 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265355","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
Study of a global calibration method for a planar parallel robot mechanism considering joint error 考虑关节误差的平面并联机器人机构全局校准方法研究
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-16 DOI: 10.1017/s0263574724000973
Qinghua Zhang, Huaming Yu, Lingbo Xie, Qinghua Lu, Weilin Chen
{"title":"Study of a global calibration method for a planar parallel robot mechanism considering joint error","authors":"Qinghua Zhang, Huaming Yu, Lingbo Xie, Qinghua Lu, Weilin Chen","doi":"10.1017/s0263574724000973","DOIUrl":"https://doi.org/10.1017/s0263574724000973","url":null,"abstract":"<p>In order to improve the positioning accuracy of industrial robots, this paper proposes a global calibration method for planar parallel robot considering joint errors, which solves the problem that the existing calibration methods only consider part of the error sources and the calibration accuracy is poor, and improves the calibration efficiency and robot positioning accuracy. Consequently, it improves calibration efficiency and the overall precision of robot positioning. Firstly, the error model of overdetermined equations combined with structural parameters is established, and the global sensitivity of each error source is analyzed. Based on the measurement data of laser tracker, the local error source is identified by the least square method, which improves the local error accuracy by 88.6%. Then, a global error spatial interpolation method based on inverse distance weighting method is proposed, and the global accuracy is improved by 59.16%. Finally, the radial basis function neural network error prediction model with strong nonlinear approximation function is designed for global calibration, and the accuracy is improved by 63.05%. Experimental results verify the effectiveness of the proposed method. This study not only provides technical support for the engineering application of this experimental platform but also provides theoretical guidance for the improvement of the accuracy of related robot platforms.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"32 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265356","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
Combining spatial clustering and tour planning for efficient full area exploration 结合空间聚类和游览规划,实现高效的全区域探索
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-13 DOI: 10.1017/s0263574724001085
Jiatong Bao, Sultan Mamun, Jiawei Bao, Wenbing Zhang, Yuequan Yang, Aiguo Song
{"title":"Combining spatial clustering and tour planning for efficient full area exploration","authors":"Jiatong Bao, Sultan Mamun, Jiawei Bao, Wenbing Zhang, Yuequan Yang, Aiguo Song","doi":"10.1017/s0263574724001085","DOIUrl":"https://doi.org/10.1017/s0263574724001085","url":null,"abstract":"<p>Autonomous exploration in unknown environments has become a critical capability of mobile robots. Many methods often suffer from problems such as exploration goal selection based solely on information gain and inefficient tour optimization. Recent reinforcement learning-based methods do not consider full area coverage and the performance of transferring learned policy to new environments cannot be guaranteed. To address these issues, a dual-stage exploration method has been proposed, which combines spatial clustering of possible exploration goals and Traveling Salesman Problem (TSP) based tour planning on both local and global scales, aiming for efficient full-area exploration in highly convoluted environments. Our method involves two stages: exploration and relocation. During the exploration stage, we introduce to generate local navigation goal candidates straight from clusters of all possible local exploration goals. The local navigation goal is determined through tour planning, utilizing the TSP framework. Moreover, during the relocation stage, we suggest clustering all possible global exploration goals and applying TSP-based tour planning to efficiently direct the robot toward previously detected but yet-to-be-explored areas. The proposed method is validated in various challenging simulated and real-world environments. Experimental results demonstrate its effectiveness and efficiency. Videos and code are available at https://github.com/JiatongBao/exploration.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"230 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186162","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 online payload identification method based on parameter difference for industrial robots 基于参数差异的工业机器人在线有效载荷识别方法
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-13 DOI: 10.1017/s026357472400105x
Tian Xu, Hua Tuo, Qianqian Fang, Jie Chen, Jizhuang Fan, Debin Shan, Jie Zhao
{"title":"An online payload identification method based on parameter difference for industrial robots","authors":"Tian Xu, Hua Tuo, Qianqian Fang, Jie Chen, Jizhuang Fan, Debin Shan, Jie Zhao","doi":"10.1017/s026357472400105x","DOIUrl":"https://doi.org/10.1017/s026357472400105x","url":null,"abstract":"<p>Accurate online estimation of the payload parameters benefits robot control. In the existing approaches, however, on the one hand, only the linear friction model was used for online payload identification, which reduced the online estimation accuracy. On the other hand, the estimation models contain much noise because of using actual joint trajectory signals. In this article, a new estimation algorithm based on parameter difference for the payload dynamics is proposed. This method uses a nonlinear friction model for the online payload estimation instead of the traditionally linear one. In addition, it considers the commanded joint trajectory signals as the computation input to reduce the model noise. The main contribution of this article is to derive a symbolic relationship between the parameter difference and the payload parameters and then apply it to the online payload estimation. The robot base parameters without payload were identified offline and regarded as the prior information. The one with payload can be solved online by the recursive least squares method. The dynamics of the payload can be then solved online based on the numerical difference of the two parameter sets. Finally, experimental comparisons and a manual guidance application experiment are shown. The results confirm that our algorithm can improve the online payload estimation accuracy (especially the payload mass) and the manual guidance comfort.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"25 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186186","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
Design of a robotic gripper for casting sorting robots with rigid–flexible coupling structures 为具有刚柔耦合结构的浇铸分拣机器人设计机器人抓手
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-13 DOI: 10.1017/s0263574724001000
Cheng-jun Wang, Biao Cheng
{"title":"Design of a robotic gripper for casting sorting robots with rigid–flexible coupling structures","authors":"Cheng-jun Wang, Biao Cheng","doi":"10.1017/s0263574724001000","DOIUrl":"https://doi.org/10.1017/s0263574724001000","url":null,"abstract":"<p>In order to solve the problem of the insufficient adaptability of the current small- and medium-sized casting sorting robot gripper, we have designed a casting sorting robot bionic gripper with rigid–flexible coupling structures based on the robot topology theory. The second-order Yeoh model was used to statically model the clamping belt in the gripper to derive the relationship between the external input air pressure and the bending angle of the driving layer, and the feasibility of multiangle bending of the driving layer was verified by finite element analysis. The maximum gripping diameter of the gripper is 140 mm, and in order to test the adaptive gripping ability of the gripper, a prototype of the casting sorting robot gripper is prepared, and the pneumatic control system and human–machine interface of the gripper are designed. After several experimental analyses, the designed casting sorting robot gripper is characterized by strong adaptability and high robustness, with a maximum load capacity of 930 g and a maximum wrap angle of 296°, which can complete the gripping operation within 1 s, and the comprehensive gripping success rate reaches 96.4%. The casting sorting robot gripper designed in the paper can provide a reference for the design and optimization of various types of shaped workpiece gripping manipulators.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"32 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186163","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
DDPG-based path planning for cable-driven manipulators in multi-obstacle environments 多障碍物环境中基于 DDPG 的缆索驱动机械手路径规划
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-13 DOI: 10.1017/s0263574724001048
Dong Zhang, Renjie Ju, Zhengcai Cao
{"title":"DDPG-based path planning for cable-driven manipulators in multi-obstacle environments","authors":"Dong Zhang, Renjie Ju, Zhengcai Cao","doi":"10.1017/s0263574724001048","DOIUrl":"https://doi.org/10.1017/s0263574724001048","url":null,"abstract":"<p>Hyper-redundant cable-driven manipulators (CDMs) are widely used for operations in confined spaces due to their slender bodies and multiple degrees of freedom. Most research focuses on their path following but not path planning. This work investigates a deep deterministic policy gradient (DDPG)-based path-planning algorithm for CDMs in multi-obstacle environments. To plan passable paths under many constraints, a DDPG algorithm is modified according to features of CDMs. To improve adaptability of planned paths, a specialized reward function is newly designed. In this function, such factors as smoothness, arrival time and distance are taken into account. Results of simulations and physical experiments are presented to demonstrate the performances of the proposed methods for planning paths of CDMs.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"13 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186182","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
Configuration design of movable heavy-duty reconfigurable posture adjustment platform with dual motion modes 具有双运动模式的可移动重型可重构姿势调整平台的配置设计
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-12 DOI: 10.1017/s026357472400064x
Rui Wang, Xiaoyan Xiong, Jinzhu Zhang, Ruilin Yuan
{"title":"Configuration design of movable heavy-duty reconfigurable posture adjustment platform with dual motion modes","authors":"Rui Wang, Xiaoyan Xiong, Jinzhu Zhang, Ruilin Yuan","doi":"10.1017/s026357472400064x","DOIUrl":"https://doi.org/10.1017/s026357472400064x","url":null,"abstract":"<p>The existing single-mode posture adjustment equipment for solar wing docking is only suitable for a limited number of satellite dimensions; it could not meet the diverse development trends of satellite models. The working range requirements are different when different-sized satellites dock with the solar wing, and the docking process is divided into two stages in this paper. While the DOFs required for the two stages are different, a movable heavy-load reconfigurable redundant posture adjustment platform (RrPAP) with dual motion modes is proposed in this paper. The RrPAP consists of a wheeled mobile platform and a reconfigurable parallel posture adjustment mechanism (PAM). The micro-motion PAM limb types are synthesized, and the comprehensive load-bearing index is proposed to select the mechanism types for heavy-load conditions. A decentralized four-limb six-degree-of-freedom (6-DOF) parallel micro-motion PAM is designed. In the macro-motion stage, for the PAM to still have a defined motion after being released from ground constraints, a serial coupling sub-chain is designed between adjacent limbs to restrict relative movement between them. A type synthesis method for symmetrically coupled mechanisms based on mechanism decoupling and motion distribution is proposed. Four types of symmetrically coupled mechanisms with multi-loop consisting of serial coupling sub-chains are synthesized by using this method. The feasibility of the proposed method is demonstrated through an example using the constraint synthesis method based on screw theory. This work provides a foundation for subsequent refinement and expansion of type synthesis theories and the selection of new types of mechanisms.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"42 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186165","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
Trace inequalities and kinematic metrics 迹不等式和运动学度量
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-12 DOI: 10.1017/s0263574724000778
Yuwei Wu, Gregory S. Chirikjian
{"title":"Trace inequalities and kinematic metrics","authors":"Yuwei Wu, Gregory S. Chirikjian","doi":"10.1017/s0263574724000778","DOIUrl":"https://doi.org/10.1017/s0263574724000778","url":null,"abstract":"<p>Kinematics remains one of the cornerstones of robotics, and over the decade, Robotica has been one of the venues in which groundbreaking work in kinematics has always been welcome. A number of works in the kinematics community have addressed metrics for rigid-body motions in multiple different venues. An essential feature of any distance metric is the triangle inequality. Here, relationships between the triangle inequality for kinematic metrics and so-called trace inequalities are established. In particular, we show that the Golden-Thompson inequality (a particular trace inequality from the field of statistical mechanics) which holds for Hermitian matrices remarkably also holds for restricted classes of real skew-symmetric matrices. We then show that this is related to the triangle inequality for <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240911135946881-0491:S0263574724000778:S0263574724000778_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$SO(3)$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240911135946881-0491:S0263574724000778:S0263574724000778_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$SO(4)$</span></span></img></span></span> metrics.</p>","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"50 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186167","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
A local collision-free motion planning strategy for hyper-redundant manipulators based on dynamic safety envelopes 基于动态安全包络的超冗余机械手局部无碰撞运动规划策略
IF 2.7 4区 计算机科学
Robotica Pub Date : 2024-09-12 DOI: 10.1017/s0263574724000791
Renjie Ju, Dong Zhang, Yan Gai, Zhengcai Cao
{"title":"A local collision-free motion planning strategy for hyper-redundant manipulators based on dynamic safety envelopes","authors":"Renjie Ju, Dong Zhang, Yan Gai, Zhengcai Cao","doi":"10.1017/s0263574724000791","DOIUrl":"https://doi.org/10.1017/s0263574724000791","url":null,"abstract":"Hyper-redundant manipulators (HRMs) exhibit promising adaptability and superior dexterity in cavity detection tasks, owing to their snake-like segmented backbones. Due to the safety concern in contactless operating tasks, reliable motion planning in a confined environment for HRMs is very challenging. However, existing expanding-based obstacle avoidance methods are not feasible in narrow environments, as they will excessively occupy free spaces required for maneuvering. In this work, a local collision-free motion planning strategy based on dynamic safety envelope (DSE) is proposed for HRMs. First, the local motion of HRMs is analyzed in detail, and DSE is proposed for the first time to describe the boundary of the collision-free area. Then, to maximize the efficient utilization of narrow spaces, a reference trajectory for HRM is roughly planned without expanding obstacles. Further, a tip-guided trajectory tracking method based on configuration prediction is proposed by considering the discrete characteristics of rigid links to avoid obstacles. During the tracking process, DSEs are applied to evaluate collision risk and optimize the configuration. Finally, to validate the effectiveness of our proposed method, simulations are conducted, followed by experiments by using a 18-degrees of freedom mobile HRM prototype system.","PeriodicalId":49593,"journal":{"name":"Robotica","volume":"7 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186169","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
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信