Int. J. Humanoid Robotics最新文献_第5页

Multilevel Image Thresholding Based on Improved Expectation Maximization (EM) and Differential Evolution Algorithm 基于改进期望最大化和差分进化算法的多级图像阈值分割

Int. J. Humanoid Robotics Pub Date : 2021-08-01 DOI: 10.1142/s0219843621500134

E. Ehsaeyan, A. Zolghadrasli

{"title":"Multilevel Image Thresholding Based on Improved Expectation Maximization (EM) and Differential Evolution Algorithm","authors":"E. Ehsaeyan, A. Zolghadrasli","doi":"10.1142/s0219843621500134","DOIUrl":"https://doi.org/10.1142/s0219843621500134","url":null,"abstract":"Multilevel image thresholding is an essential step in the image segmentation process. Expectation Maximization (EM) is a powerful technique to find thresholds but is sensitive to the initial points. Differential Evolution (DE) is a robust metaheuristic algorithm that can find thresholds rapidly. However, it may be trapped in the local optimums and premature convergence occurs. In this paper, we incorporate EM algorithm to DE and introduce a novel algorithm called EM+DE which overcomes these shortages and can segment images better than EM and DE algorithms. In the proposed method, EM estimates Gaussian Mixture Model (GMM) coefficients of the histogram and DE tries to provide good volunteer solutions to EM algorithm when EM converges in local areas. Finally, DE fits GMM parameters based on Root Mean Square Error (RMSE) to reach the fittest curve. Ten standard test images and six famous metaheuristic algorithms are considered and result on global fitness. PSNR, SSIM, FSIM criteria and the computational time are given. The experimental results prove that the proposed algorithm outperforms the EM and DE as well as EM+ other natural-inspired algorithms in terms of segmentation criteria.","PeriodicalId":312776,"journal":{"name":"Int. J. Humanoid Robotics","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126978455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic Walking Analysis of an Underactuated Biped Robot with Asymmetric Structure 非对称结构欠驱动双足机器人动力学行走分析

Int. J. Humanoid Robotics Pub Date : 2021-08-01 DOI: 10.1142/s0219843621500146

B. Beigzadeh, S. Razavi

{"title":"Dynamic Walking Analysis of an Underactuated Biped Robot with Asymmetric Structure","authors":"B. Beigzadeh, S. Razavi","doi":"10.1142/s0219843621500146","DOIUrl":"https://doi.org/10.1142/s0219843621500146","url":null,"abstract":"Owing to their nonlinear structures and dynamics, bipedal walking robots are commonly used as appropriate case studies for nonlinear modeling and control. In this study, the dynamics of a point-feet 4-link biped robot having asymmetric structure is studied. This asymmetry appears on the robot’s legs such that one leg of the robot does have an active knee while the other is knee-less. In this way, the style and analysis of each step depends on which leg is the stance leg. Although the stable steady state behavior of the system is purely periodic, the gait cycle does consist of two sequential steps. Since each step includes a continuous phase followed by an impact phase, hence, we need to model the system as a multiphase (4-phase) hybrid system. The main purpose of this research is to find stable gating pattern and employ appropriate controller to make sure that the gating is accomplished in an asymptotically stable manner. A combination of feedback linearization and finite-time controllers is used to control the walking posture, and the stability of the whole behavior is investigated by analysis of a one-dimensional Poincaré map. Simulation results successfully support the modeling and control approach.","PeriodicalId":312776,"journal":{"name":"Int. J. Humanoid Robotics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124463143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Cooperative Control of Manipulator and Human Operator for Direct Teaching 面向直接教学的机械手与操作人员协同控制

Int. J. Humanoid Robotics Pub Date : 2021-06-14 DOI: 10.1142/S0219843621500079

Jong-woo An, Youdong Zhao, Jangmyung Lee

引用次数: 1

An O(N) Algorithm for the Computation of the Centroidal Dynamics with Application in the Postural Balance of a Humanoid Robot Using Whole Body Control 一种计算质心动力学的O(N)算法及其在仿人机器人全身控制姿态平衡中的应用

Int. J. Humanoid Robotics Pub Date : 2021-06-09 DOI: 10.1142/S0219843621500109

Jose C. Rojas-Rodriguez, A. Aguilar-Bustos, E. Bugarin

引用次数: 2

Dead-Zone ESO Based Sensorless Force/Position Control for Dynamic Contact Systems 基于死区ESO的动态接触系统无传感器力/位置控制

Int. J. Humanoid Robotics Pub Date : 2021-06-09 DOI: 10.1142/S0219843621500092

Mingchao Wang, Yuan Yuan, Huanhuan Yuan

引用次数: 0

The Math of Tasks: A Domain Specific Language for Constraint-Based Task Specification 任务数学:用于基于约束的任务规范的领域特定语言

Int. J. Humanoid Robotics Pub Date : 2021-06-09 DOI: 10.1142/S0219843621500080

E. Hoffman, N. Tsagarakis

引用次数: 2

Locomotion Adaption for Hydraulic Humanoid Wheel-Legged Robots Over Rough Terrains 液压类人轮腿机器人在粗糙地形上的运动适应

Int. J. Humanoid Robotics Pub Date : 2021-05-04 DOI: 10.1142/S0219843621500018

Xu Li, Songyuan Zhang, Haitao Zhou, Haibo Feng, Yili Fu

{"title":"Locomotion Adaption for Hydraulic Humanoid Wheel-Legged Robots Over Rough Terrains","authors":"Xu Li, Songyuan Zhang, Haitao Zhou, Haibo Feng, Yili Fu","doi":"10.1142/S0219843621500018","DOIUrl":"https://doi.org/10.1142/S0219843621500018","url":null,"abstract":"Compared with the traditional hydraulic humanoid robots, the WLR-II, a novel hydraulic wheel-legged robot developed by using hose-less design, can significantly increase the reliability and maneuverability. The WLR-II combines the rough-terrain capability of legs with the efficiency of wheels. In this paper, a novel framework called rough-terrain adaption framework (RTAF) is presented which allows WLR-II to move on both flat terrains and terrains with unmodeled contact dynamics. RTAF is a hierarchical framework, which has a high-level balance controller and a low-level impedance controller that a high-performance nested torque controller with feed-forward velocity compensation is used. The low-level impedance controller for the hydraulic-driven unit can cancel out the load dynamics influence such as unexpected terrain disturbances and increase the force-tracking performance. With the high-level balance controller, the robot is able to handle unexpected terrain disturbances through wheel-ground force estimation, pitch/roll balance control and impedance parameter regulator. The proposed approach is suitable for a wheel-legged humanoid robot to manage balance through torque control at joints and regulate force-based interaction on rough terrains. The performance of the proposed RTAF is evaluated on variable gradient slopes and grassland which are the typical rough-terrain scenarios for real-world applications. The experimental results reveal that the maximum speed of grassland movement can reach 3 km/h.","PeriodicalId":312776,"journal":{"name":"Int. J. Humanoid Robotics","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122826449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Grasp Pose Detection Based on Shape Simplification 基于形状简化的抓取姿态检测

Int. J. Humanoid Robotics Pub Date : 2021-04-19 DOI: 10.1142/S0219843621500067

Chuqing Cao, Hanwei Liu

引用次数: 0

HANDSHAKE: HANDling System for Human Autonomous KEeping 握手:人类自主保持的处理系统

Int. J. Humanoid Robotics Pub Date : 2021-04-09 DOI: 10.1142/S0219843621500031

G. G. Muscolo

{"title":"HANDSHAKE: HANDling System for Human Autonomous KEeping","authors":"G. G. Muscolo","doi":"10.1142/S0219843621500031","DOIUrl":"https://doi.org/10.1142/S0219843621500031","url":null,"abstract":"This paper presents a novel biped-wheeled-wearable machine, named HANDSHAKE, and obtained by an evolution of two robots presented in other works: one flexible-wheeled leg and one biped-flexible-wheeled robot. A critical design analysis of these two robots helped the author to propose a novel machine able to revolutionize the lower body exoskeletons’ world. Conceptual and functional design, mechanical behavior (kinematics and dynamics), and multibody simulation of the biped-wheeled exoskeleton are presented in this paper, and a first reduced scale prototype is used to show the feasibility of the proposed solution. The simple control architecture used in this work underlines the enormous advantages to use the HANDSHAKE system for people with a complete absence of mobility, which are completely supported by this machine. This is possible thanks to the wheeled feet of the HANDSHAKE system which allow to support more weights respect to the classical exoskeletons, available on market and literature. The proposed machine increases stability, dynamic balance, autonomy, reducing power supply and complexity in comparison with classical exoskeleton systems because the wheeled feet are always in contact with the ground. These advantages, recognized in humanoid robots, may be used also in exoskeletons.","PeriodicalId":312776,"journal":{"name":"Int. J. Humanoid Robotics","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128042401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Whole-Body Compliant Motion by Sensor Integration of an EHA-Driven Humanoid Hydra 基于传感器集成的eha驱动人形九头蛇全身柔顺运动

Int. J. Humanoid Robotics Pub Date : 2021-03-02 DOI: 10.1142/S021984362150002X

Tianyi Ko, Kazuya Murotani, Ko Yamamoto, Yoshihiko Nakamura

{"title":"Whole-Body Compliant Motion by Sensor Integration of an EHA-Driven Humanoid Hydra","authors":"Tianyi Ko, Kazuya Murotani, Ko Yamamoto, Yoshihiko Nakamura","doi":"10.1142/S021984362150002X","DOIUrl":"https://doi.org/10.1142/S021984362150002X","url":null,"abstract":"Joints’ backdrivability is desired for robots that perform tasks contacting the environment, in addition to the high torque and fast response property. The electro-hydrostatic actuator (EHA) is an approach to realize force-sensitive robots. To experimentally confirm the performance of a biped robot driven by EHAs, we developed the fully electro-hydrostatically driven humanoid robot Hydra. In this paper, we evaluate the whole-body control performance realized by integrating encoders, pressure sensors, and IMU through a high-speed communication bus to the distributed whole-body control system. We report the first example of bipedal locomotion by an EHA-driven robot in both position-controlled and torque-controlled approaches. The robot could keep the balance even when the ground condition was changing impulsively and utilize its high joint backdrivability to absorb a disturbance by the null space compliance. We also report practical challenges in implementing compliant control in real hardware with limitations in parameter accuracy, torque, and response. We experimentally confirmed that the resolved viscoelasticity control (RVC), which has indirect feedback of operational space tasks by projecting the operational space feedback gain to the joint space one, was effective to tune a proper gain to stabilize the center-of-mass motion while avoiding joint-level oscillation invoked by the control bandwidth limitation. The attached multimedia file includes the video of all experiments presented in the paper.","PeriodicalId":312776,"journal":{"name":"Int. J. Humanoid Robotics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130918906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5