Design and kinematics of a novel double-ring truss deployable antenna mechanism

Abstract This paper aims to present the topological structure design and kinematic analysis of a novel double-ring truss deployable satellite antenna mechanism. First, a new topological scheme and a new rectangular prism deployable linkage unit are proposed for constructing the kind of antenna mechanisms. Second, the degree-of-freedom (DOF) of the deployable unit and the antenna mechanism are analyzed based on structure decomposition and screw theory. Third, the kinematic model of the double-ring truss deployable antenna mechanism is established based on its structural characteristics. Finally, a typical numerical example is used to illustrate the effectiveness of the designed mechanism and the established kinematic model. The new double-ring truss deployable antenna mechanism consists of the units with the better structural symmetry, and has simpler joint axis layouts, comparing with the same type of most existing mechanisms.

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A Novel Two-Layer and Two-Loop Deployable Linkage With Accurate Vertical Straight-Line Motion

Journal of Mechanical Design ◽

10.1115/1.4046239 ◽

2020 ◽

Vol 142 (10) ◽

Author(s):

Wen-ao Cao ◽

De Zhang ◽

Huafeng Ding

Keyword(s):

Screw Theory ◽

Kinematic Model ◽

Degree Of Freedom ◽

Kinematics Model ◽

Vertical Straight Line ◽

Straight Line ◽

Structure Decomposition

Abstract This paper presents a novel two-layer and two-loop spatial deployable linkage which can only accurately output vertical straight-line motion. First, the degree-of-freedom (DOF) of the linkage is analyzed based on structure decomposition and screw theory, and the characteristic of the straight-line motion of the linkage is verified by checking the output twist of the end platform. Then, the kinematic model of the mechanism is established based on the conditions of the straight-line motion and the single DOF. Finally, several potentially typical applications of the linkage are exhibited. The straight-line linkage has relatively simple joint layouts and kinematics model and can be used as a deployable unit to construct some special deployable mechanisms.

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On the Correctness and Strictness of the Position and Orientation Characteristic Equation for Topological Structure Design of Robot Mechanisms

Journal of Mechanisms and Robotics ◽

10.1115/1.4023871 ◽

2013 ◽

Vol 5 (2) ◽

Cited By ~ 13

Author(s):

Ting-Li Yang ◽

An-Xin Liu ◽

Hui-Ping Shen ◽

Yu-Feng Luo ◽

Lu-Bin Hang ◽

...

Keyword(s):

Topological Structure ◽

Screw Theory ◽

Structure Design ◽

Parallel Mechanisms ◽

Operation Rules ◽

Structure Synthesis ◽

Union Operation ◽

Intersection Operation ◽

Velocity Characteristic ◽

Position And Orientation

Position and orientation characteristic (POC) equations for topological structure synthesis of serial and parallel mechanisms were proposed in a published paper by the authors. This paper will further prove the correctness and strictness of the theoretical foundation for POC equations and also be a reply to the reviewers of our follow-up papers. The main contents of this paper include: symbolic representation of mechanism topological structure and its invariance, velocity characteristic (VC) set and POC set of link and its invariance, one-to-one correspondence between elements of the VC set and POC set, POC equations for the serial mechanism and 10 corresponding “union” operation rules, and POC equations for the parallel mechanism and 14 corresponding “intersection” operation rules. In addition, the interrelations and differences among three methods (POC set based method, screw theory based method, and displacement subgroup based method) for mechanism topological structure design are concluded.

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Multi-Branch Cable Harness Layout Design Based on Genetic Algorithm with Probabilistic Roadmap Method

Chinese Journal of Mechanical Engineering ◽

10.1186/s10033-021-00544-9 ◽

2021 ◽

Vol 34 (1) ◽

Author(s):

Yingfeng Zhao ◽

Jianhua Liu ◽

Jiangtao Ma ◽

Linlin Wu

Keyword(s):

Genetic Algorithm ◽

Topological Structure ◽

Design Method ◽

Route Planning ◽

Layout Design ◽

Structure Design ◽

Prototype System ◽

Cable Harness ◽

Probabilistic Roadmap ◽

Probabilistic Roadmap Method

AbstractCurrent studies on cable harness layouts have mainly focused on cable harness route planning. However, the topological structure of a cable harness is also extremely complex, and the branch structure of the cable harness can affect the route of the cable harness layout. The topological structure design of the cable harness is a key to such a layout. In this paper, a novel multi-branch cable harness layout design method is presented, which unites the probabilistic roadmap method (PRM) and the genetic algorithm. First, the engineering constraints of the cable harness layout are presented. An obstacle-based PRM used to construct non-interference and near to the surface roadmap is then described. In addition, a new genetic algorithm is proposed, and the algorithm structure of which is redesigned. In addition, the operation probability formula related to fitness is proposed to promote the efficiency of the branch structure design of the cable harness. A prototype system of a cable harness layout design was developed based on the method described in this study, and the method is applied to two scenarios to verify that a quality cable harness layout can be efficiently obtained using the proposed method. In summary, the cable harness layout design method described in this study can be used to quickly design a reasonable topological structure of a cable harness and to search for the corresponding routes of such a harness.

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Fabrication of Polycaprolactone/Nano Hydroxyapatite (PCL/nHA) 3D Scaffold with Enhanced In Vitro Cell Response via Design for Additive Manufacturing (DfAM)

Polymers ◽

10.3390/polym13091394 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1394

Author(s):

Yong Sang Cho ◽

So-Jung Gwak ◽

Young-Sam Cho

Keyword(s):

Mechanical Properties ◽

Cell Response ◽

Structural Characteristics ◽

Structure Design ◽

Compressive Modulus ◽

Control Group ◽

Design For Additive Manufacturing ◽

3D Scaffold ◽

3D Printed

In this study, we investigated the dual-pore kagome-structure design of a 3D-printed scaffold with enhanced in vitro cell response and compared the mechanical properties with 3D-printed scaffolds with conventional or offset patterns. The compressive modulus of the 3D-printed scaffold with the proposed design was found to resemble that of the 3D-printed scaffold with a conventional pattern at similar pore sizes despite higher porosity. Furthermore, the compressive modulus of the proposed scaffold surpassed that of the 3D-printed scaffold with conventional and offset patterns at similar porosities owing to the structural characteristics of the kagome structure. Regarding the in vitro cell response, cell adhesion, cell growth, and ALP concentration of the proposed scaffold for 14 days was superior to those of the control group scaffolds. Consequently, we found that the mechanical properties and in vitro cell response of the 3D-printed scaffold could be improved by kagome and dual-pore structures through DfAM. Moreover, we revealed that the dual-pore structure is effective for the in vitro cell response compared to the structures possessing conventional and offset patterns.

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Dynamic Analysis on a Cable-Driven Interventional Active Catheter Using Kane's Method Combined with Screw Theory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.527.140 ◽

2014 ◽

Vol 527 ◽

pp. 140-145

Author(s):

Da Xu Zhao ◽

Bai Chen ◽

Guo Zhong Shou ◽

Yu Qi Gu

Keyword(s):

Mathematical Model ◽

Dynamic Analysis ◽

Motion Control ◽

Screw Theory ◽

Driving Forces ◽

Structure Design ◽

Kinematics And Dynamics ◽

Existing Problems ◽

Blind Area ◽

The Mathematical Model

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.

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Automatic Mode-Matching Method for MEMS Disk Resonator Gyroscopes Based on Virtual Coriolis Force

Micromachines ◽

10.3390/mi11020210 ◽

2020 ◽

Vol 11 (2) ◽

pp. 210

Author(s):

Zhihu Ruan ◽

Xukai Ding ◽

Zhengcheng Qin ◽

Jia Jia ◽

Hongsheng Li

Keyword(s):

Coriolis Force ◽

Electrostatic Force ◽

Structural Characteristics ◽

Structure Design ◽

Driving Voltage ◽

Mode Matching ◽

Matching Method ◽

Disk Resonator ◽

Mode Matching Method ◽

Automatic Mode

An automatic mode-matching method for MEMS (Micro-electromechanical Systems) disk resonator gyroscopes (DRGs) based on virtual Coriolis force is presented in this paper. For this mode-matching method, the additional tuning electrodes are not required to be designed, which simplifies the structure design. By using the quadratic relationship between the driving voltage and the electrostatic force, the virtual Coriolis force is obtained by applying an AC voltage whose frequency is half of the driving mode resonant frequency to the sense electrode. The phase difference between the virtual Coriolis force and the sense output signal is used for mode-matching. The structural characteristics and electrode distribution of the DRG are briefly introduced. Moreover, the mode-matching theories of the DRG are studied in detail. The scheme of the mode-matching control system is proposed. Simultaneously, the feasibility and effectiveness of the mode-matching method are verified by system simulation. The experimental results show that under the control of mode-matching at room temperature, the bias instability is reduced from 30.7575 ° /h to 2.8331 ° /h, and the Angle Random Walk (ARW) decreases from 1.0208 ° / h to 0.0524 ° / h . Compared with the mode mismatch condition, the ARW is improved by 19.48 times.

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Multi-Loop Rover: A Kind of Modular Rolling Robot Constructed by Multi-Loop Linkages

Journal of Mechanisms and Robotics ◽

10.1115/1.4048225 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Yaobin Tian ◽

Xianwen Kong ◽

Kun Xu ◽

Xilun Ding

Keyword(s):

Topological Structure ◽

Inverse Kinematics ◽

Modular Design ◽

Screw Theory ◽

Deformation Properties ◽

Physical Prototype ◽

Forward And Inverse Kinematics ◽

Rolling Robot

Abstract This paper proposes a new kind of modular rolling robot called multi-loop rover (MLR), which is essentially a multi-loop linkage that is able to roll and switch its rolling directions. For ease of rolling, the MLR retains a multi-loop topological structure composed of a number of strut and node modules. First, the modular design and assembling method are introduced to construct an MLR. Then, the mobility is analyzed based on screw theory, and a brief formula is presented to calculate the degree-of-freedoms of the robot. The results show that all node modules only have translational motions, which can significantly reduce the complexity of kinematics. The forward and inverse kinematics are conducted to show the deformation properties. Based on the kinematic rolling principle, the morphing strategies for rolling and turning functions are developed. Finally, a physical prototype is manufactured and a serial of experiments are carried out to verify the proposed method.

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Position and Orientation Characteristic Equation for Topological Design of Parallel Mechanisms

Volume 2: 32nd Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2008-49075 ◽

2008 ◽

Cited By ~ 1

Author(s):

Ting-Li Yang ◽

An-Xin Liu ◽

Qiong Jin ◽

Yu-Feng Luo ◽

Hui-Ping Shen ◽

...

Keyword(s):

Topological Structure ◽

Parallel Mechanism ◽

Screw Theory ◽

Parallel Mechanisms ◽

Output Link ◽

Geometrical Meaning ◽

Operation Rules ◽

The Matrix ◽

Position And Orientation ◽

Symbolic Operation

This paper presents the explicit mapping relations between topological structure of parallel mechanism and position and orientation characteristic (in short, POC) of its motion output link. It deals with: (1) The symbolic representation and the invariant of topological structure of mechanism; (2) The matrix representation of POC of motion output link; (3) The POC equations of parallel mechanism and its symbolic operation rules. The symbolic operation involves simple mathematic tools and fewer operation rules, and has clear geometrical meaning. So, it is easy to use. The forward operation of the POC equations can be used for structural analysis; its inverse operation can be used for structural synthesis. The method proposed in this paper is totally different from the methods based on screw theory and based on displacement subgroup.

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Kinematic modeling and control of mobile robot for large-scale workpiece machining

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420933708 ◽

2020 ◽

pp. 095440542093370

Author(s):

Bo Tao ◽

Xingwei Zhao ◽

Sijie Yan ◽

Han Ding

Keyword(s):

Mobile Robot ◽

Large Scale ◽

Screw Theory ◽

Kinematic Model ◽

Speed Control ◽

Constant Speed ◽

Mobile Platform ◽

Robot Arm ◽

Kinematic Modeling ◽

Robotic Machining

Safety and reliability are significant in the sense of robotic machining for large-scale workpieces. In this article, a control scheme is proposed to ensure the safe motion of the mobile robot. Screw theory is used to analyze the motion of the mobile robot. The mobile platform with Mecanum wheels can be considered as a mechanism with four driven screws in series. An auxiliary reference position of the mobile platform is calculated based on the kinematic model, and the motion of the mobile platform and robot arm can be decoupled to handle its redundant degrees of freedom. Constant speed control is investigated to reduce the interaction force between the robot and platform. Experiments are conducted on the mobile robotic machining task for a large-scale wind turbine blade. The mobile robot moves steadily and smoothly owing to the constant speed control with an auxiliary target.

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