Journal of Mechanisms and Robotics-Transactions of the Asme最新文献

On the Construction of Confidence Regions for Uncertain Planar Displacements. 论不确定平面位移置信区的构建

IF 2.2 4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2024-08-01 Epub Date: 2024-01-12 DOI: 10.1115/1.4064281

Zihan Yu, Qiaode Jeffrey Ge, Mark P Langer, Mona Arbab

{"title":"On the Construction of Confidence Regions for Uncertain Planar Displacements.","authors":"Zihan Yu, Qiaode Jeffrey Ge, Mark P Langer, Mona Arbab","doi":"10.1115/1.4064281","DOIUrl":"10.1115/1.4064281","url":null,"abstract":"This paper studies the statistical concept of confidence region for a set of uncertain planar displacements with a certain level of confidence or probabilities. Three different representations of planar displacements are compared in this context and it is shown that the most commonly used representation based on the coordinates of the moving frame is the least effective. The other two methods, namely the exponential coordinates and planar quaternions, are equally effective in capturing the group structure of SE(2). However, the former relies on the exponential map to parameterize an element of SE(2), while the latter uses a quadratic map, which is often more advantageous computationally. This paper focus on the use of planar quaternions to develop a method for computing the confidence region for a given set of uncertain planar displacements. Principal component analysis (PCA) is another tool used in our study to capture the dominant direction of movements. To demonstrate the effectiveness of our approach, we compare it to an existing method called rotational and translational confidence limit (RTCL). Our examples show that the planar quaternion formulation leads to a swept volume that is more compact and more effective than the RTCL method, especially in cases when off-axis rotation is present.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11344949/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142057025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Computation of Mean and Variance of Spatial Displacements. 空间位移的均值和方差计算

IF 2.2 4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2024-01-01 Epub Date: 2023-03-28 DOI: 10.1115/1.4057046

Qiaode Jeffrey Ge, Zihan Yu, Mona Arbab, Mark P Langer

{"title":"On the Computation of Mean and Variance of Spatial Displacements.","authors":"Qiaode Jeffrey Ge, Zihan Yu, Mona Arbab, Mark P Langer","doi":"10.1115/1.4057046","DOIUrl":"10.1115/1.4057046","url":null,"abstract":"This paper studies the problem of computing an average (or mean) displacement from a set of given spatial displacements using three types of parametric representations: Euler angles and translation vectors, unit quaternions and translation vectors, and dual quaternions. It is shown that the use of Euclidean norm in the space of unit quaternions reduces the problem to that of computing the mean for each quaternion component separately and independently. While the resulting algorithm is simple, a change in the sign of a unit quaternion could lead to an incorrect result. A novel kinematic measure based on dual quaternions is introduced to capture the separation between two spatial displacements. This kinematic measure is used to define the variance of a set of displacements, which is then used to formulate a constrained least squares minimization problem. It is shown that the problem decomposes into that of finding the optimal translation vector and the optimal unit quaternion. The former is simply the centroid of the set of translation vectors and the latter is obtained as the eigenvector corresponding to the least eigenvalue of a 4 × 4 positive definite symmetric matrix. In addition, it is found that the weight factor used in combining rotations and translations in the formulation does not play a role in the final outcome. Examples are provided to show the comparisons of these methods.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11348399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44880190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Separable Tendon-Driven Robotic Manipulator with a Long, Flexible, Passive Proximal Section. 具有长、柔性、被动近端截面的可分离肌腱驱动机器人机械手

IF 2.6 4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-12-01 Epub Date: 2023-05-02 DOI: 10.1115/1.4062354

Christian DeBuys, Florin C Ghesu, Jagadeesan Jayender, Reza Langari, Young-Ho Kim

{"title":"Separable Tendon-Driven Robotic Manipulator with a Long, Flexible, Passive Proximal Section.","authors":"Christian DeBuys, Florin C Ghesu, Jagadeesan Jayender, Reza Langari, Young-Ho Kim","doi":"10.1115/1.4062354","DOIUrl":"10.1115/1.4062354","url":null,"abstract":"This work tackles practical issues which arise when using a tendon-driven robotic manipulator (TDRM) with a long, flexible, passive proximal section in medical applications. Tendon-driven devices are preferred in medicine for their improved outcomes via minimally invasive procedures, but TDRMs come with unique challenges such as sterilization and reuse, simultaneous control of tendons, hysteresis in the tendon-sheath mechanism, and unmodeled effects of the proximal section shape. A separable TDRM which overcomes difficulties in actuation and sterilization is introduced, in which the body containing the electronics is reusable and the remainder is disposable. An open-loop redundant controller which resolves the redundancy in the kinematics is developed. Simple linear hysteresis compensation and re-tension compensation based on the physical properties of the device are proposed. The controller and compensation methods are evaluated on a testbed for a straight proximal section, a curved proximal section at various static angles, and a proximal section which dynamically changes angles; and overall, distal tip error was reduced.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10845131/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42672655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Redundant Serial Manipulator Inverse Position Kinematics and Dynamics 冗余串联机械手逆位置运动学与动力学

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-10 DOI: 10.1115/1.4064047

Edward J. Haug

引用次数: 0

Ring origami spring capable of eversion morphing 环形折纸弹簧，可伸缩变形

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063978

Yu Zou, Chen Qianying, Lu Lu, Xiying Li, Hongyuan Li, Li-Hua Shao, Huiling Duan, Pengyu Lv

引用次数: 0

PhyNRnet: Physics-informed Newton-Raphson Network for Forward Kinematics Solution of Parallel Manipulators 基于物理信息的牛顿-拉夫森网络并联机器人正解

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063977

Chongjian He, Wei Guo, Yanxia Zhu, Lizhong Jiang

{"title":"PhyNRnet: Physics-informed Newton-Raphson Network for Forward Kinematics Solution of Parallel Manipulators","authors":"Chongjian He, Wei Guo, Yanxia Zhu, Lizhong Jiang","doi":"10.1115/1.4063977","DOIUrl":"https://doi.org/10.1115/1.4063977","url":null,"abstract":"Abstract Despite significant performance advantages, the intractable forward kinematics have always restricted the application of parallel manipulators to small posture spaces. Traditional analytical method and Newton-Raphson method usually cannot solve this problem well due to lack of generality or latent divergence. To address this issue, this study employs recent advances in deep learning to propose a novel physics-informed Newton-Raphson network (PhyNRnet) to rapidly and accurately solve this forward kinematics problem for general parallel manipulators. The main strategy of PhyNRnet is to combine the Newton-Raphson method with the neural network, which helps to significantly improve the accuracy and convergence speed of the model. In addition, to facilitate the network optimization, semi-autoregression, hard imposition of initial/boundary conditions (I/BCs), batch normalization, etc. are developed and applied in PhyNRnet. Unlike previous data-driven paradigms, PhyNRnet adopts the physics-informed loss functions to guide the network optimization, which gives the model clear physical meaning and helps improve generalization ability. Finally, the performance of PhyNRnet is verified by three parallel manipulator paradigms with large postures, where the Newton-Raphson method has generally diverged. Besides, the efficiency analysis shows that PhyNRnet consumes only a small amount of time at each time step, which meets the real-time requirements.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135934921","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 Novel Large-Stroke Compliant Constant-Torque Mechanism Based on Chained Beam-Constraint Model 基于链梁约束模型的新型大行程柔性恒转矩机构设计

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063980

Thanh-Vu Phan, Van Men Truong, Huy-Tuan Pham, Van-Khien Nguyen

引用次数: 0

Design and Analysis of a Novel Redundant Parallel Mechanism for Long Bone Fracture Reduction 一种新型冗余并联长骨骨折复位机构设计与分析

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063981

Tingting Su, Quan Yuan, Xu Liang, Yuchen Yan, Haojian Zhang, Xianjie Jian, Guangping He, Quan-Liang Zhao

{"title":"Design and Analysis of a Novel Redundant Parallel Mechanism for Long Bone Fracture Reduction","authors":"Tingting Su, Quan Yuan, Xu Liang, Yuchen Yan, Haojian Zhang, Xianjie Jian, Guangping He, Quan-Liang Zhao","doi":"10.1115/1.4063981","DOIUrl":"https://doi.org/10.1115/1.4063981","url":null,"abstract":"Abstract In recent years, parallel robots have become a hot research topic in trauma fracture treatment because of their high precision, high load capacity, and compact structure. However, compared with serial robots, parallel robots have disadvantages like smaller workspaces and more complex dexterity. In this paper, a novel redundant parallel mechanism (RPM) for long bone fracture reduction is proposed based on Stewart parallel mechanism (SPM). 6 kinematically redundant DOFs (Degrees of freedom) are added to the RPM. First, the kinematics of the RPM is established, and its workspace is calculated. The analysis results indicate that the position workspace of the RPM is about 19 times larger than that of the SPM. The RPM has a similar range of torsion angles as the SPM, but a more extensive range of tilt angles than the SPM. Second, the singularities of the two parallel mechanisms are compared based on the dimensionally homogeneous Jacobian matrix. The results show that the dexterity of the RPM is much better than the SPM. Third, a multi-parameter multi-objective optimization method is proposed to optimize the geometry parameters of the RPM. The statics of the RPM is analyzed by finite element analysis. To further expand the performance of the RPM, the unfixed RPM (URPM) is proposed. The analysis results show that the URPM is superior to the RPM in terms of workspace and dexterity. Finally, experiments are conducted to verify the effectiveness of the proposed methods in this paper.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135934439","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 Concentric Tube Robot Design for Safe Intracerebral Hemorrhage Removal 安全脑出血清除同心管机器人优化设计

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-11-02 DOI: 10.1115/1.4063979

Zhefeng Huang, Hussain Alkhars, Anthony Gunderman, Dimitri Sigounas, Kevin Cleary, Yue Chen

{"title":"Optimal Concentric Tube Robot Design for Safe Intracerebral Hemorrhage Removal","authors":"Zhefeng Huang, Hussain Alkhars, Anthony Gunderman, Dimitri Sigounas, Kevin Cleary, Yue Chen","doi":"10.1115/1.4063979","DOIUrl":"https://doi.org/10.1115/1.4063979","url":null,"abstract":"Abstract Purpose: The purpose of this paper is to investigate the geometrical design and path planning of Concentric tube robots (CTR) for intracerebral hemorrhage (ICH) evacuation, with a focus on minimizing the risk of damaging white matter tracts and cerebral arteries. Methods: To achieve our objective, we propose a parametrization method describing a general class of CTR geometric designs. We present mathematical models that describe the CTR design constraints and provide the calculation of a path risk value. We then use a genetic algorithm to determine the optimal tube geometry for targeting within the brain. Results: Our results show that a multi-tube CTR design can significantly reduce the risk of damaging critical brain structures compared to the conventional straight tube design. However, there is no significant relationship between the path risk value and the number and shape of the additional inner curved tubes. Conclusion: Considering the challenges of CTR hardware design, fabrication, and control, we conclude that the most practical geometry for a CTR path in ICH treatment is a straight outer tube followed by a planar curved inner tube. These findings have important implications for the development of safe and effective CTRs for ICH evacuation by enabling dexterous manipulation to minimize damage to critical brain structures.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135934287","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 Mirrored Approach to Generate Spatial Deployable Assemblies using Tripod-scissor Units 使用三脚架-剪刀单元生成空间可展开组件的镜像方法

4区计算机科学

Journal of Mechanisms and Robotics-Transactions of the Asme Pub Date : 2023-10-20 DOI: 10.1115/1.4063872

Yuan Liao, Sudarshan Krishnan

{"title":"A Mirrored Approach to Generate Spatial Deployable Assemblies using Tripod-scissor Units","authors":"Yuan Liao, Sudarshan Krishnan","doi":"10.1115/1.4063872","DOIUrl":"https://doi.org/10.1115/1.4063872","url":null,"abstract":"Abstract A tripod-scissor unit, unlike planar scissor pairs, consists of three rods connected at an intermediate joint thus forming a spatially transformable unit. Geometrically, a tripod-scissor unit is axisymmetric but does not possess reflectional symmetry. This paper proposes a mirrored assembly approach wherein two units are connected symmetrically about the mirroring plane. The assembly approach results in different geometric conditions and motion characteristics. Two types of four-unit deployable blocks were made – one out of straight and the other of angulated members. Design equations were developed to study the influence of member geometry and assembly method on the structure's form and transformation. Digital models helped to validate the analytical results and to simulate the motion of the structures. More sample structures are presented to demonstrate the assembly of multiple units using the mirrored approach. The analysis shows that the mirrored assembly tripod-scissors result in a new generation of mechanisms with different transformation characteristics. Closed polyhedral forms with a high expansion ratio are possible.","PeriodicalId":49155,"journal":{"name":"Journal of Mechanisms and Robotics-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135570109","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