Type Synthesis of a Family of 4-, 5- and 6-DOF Sea Lion Ball Mechanisms With Three Limbs

2015 ◽  
Author(s):  
Rongfu Lin ◽  
Weizhong Guo ◽  
Feng Gao
Keyword(s):  
Synthesis Method ◽  
Lower Limbs ◽  
The Novel ◽  
Type Synthesis ◽  
Sea Lion ◽  
End Effector ◽  
Motion Patterns ◽  
In Series ◽  
Rotational Motions ◽  
Sets Theory

In this paper, a family of novel mechanisms with three limbs is proposed. The novel family of mechanisms looks like a sea lion playing a ball therefore we called it the sea lion ball mechanism (SLBM). Its characteristics are described in detail below. The SLBM is composed of an upper part and a lower part connected together by three limbs in series. One of the most important advantages of SLBMs is that the translational and rotational motions are partially decoupled: the end-effector position is only determined by the inputs of the lower part, while the rotational angles are mainly determined by the inputs of the upper part. Then, the procedures for the type synthesis of SLBMs with three limbs are proposed based on the GF sets theory and the concept of virtual chain. Furthermore, according to the proposed procedure, 4-, 5- and 6-DOF SLBMs are investigated in terms of type synthesis based on a concept of upper-lower combination. The synthesis method of the upper limbs and lower limbs are presented. The PR and Pa joints are introduced to realize the functions of R and P joints to achieve more mechanisms. The six types kinematic limbs with 3T3R, 3T2R, 2T3R, 3T1R, 2T2R and 1T3R motion patterns of SLBMs are designed. Lastly, several novel 4-, 5- and 6-DOF SLBMs are proposed and sketched. The concept of the upper-lower combination may provide a new idea for type synthesis of decoupled parallel mechanism.

Type Synthesis of a Family of Novel Four, Five, and Six Degrees-of-Freedom Sea Lion Ball Mechanisms With Three Limbs

2016 ◽  
Vol 8 (2) ◽  
Author(s):  
Rongfu Lin ◽  
Weizhong Guo ◽  
Feng Gao
Keyword(s):  
Mathematical Models ◽  
Degrees Of Freedom ◽  
Type Synthesis ◽  
Sea Lion ◽  
End Effector ◽  
Motion Patterns ◽  
Six Degrees Of Freedom ◽  
Rotational Motions ◽  
The Given ◽  
Actuated Joints

A family of novel mechanisms with three limbs called sea lion ball mechanisms (SLBMs) is investigated that looks like a sea lion playing with a ball. The SLBM-type mechanism is composed of an upper part and a lower part connected together by three limbs in parallel, and the translational and rotational motions are fully/partially decoupled. The end-effector position is determined by inputs of the lower part, while the posture is mainly determined by inputs of the upper part. First, two compositional principles are abstracted and the corresponding mathematical models are built for the SLBM-type mechanisms that the commutative feature of the SLBMs is found. Then, two type synthesis procedures containing five steps are proposed correspondingly. Following the procedure, a family of novel four, five, and six degrees-of-freedom (DOF) SLBM-type mechanisms is synthesized systematically. The motion patterns of the limbs are enumerated according to the given desired ones of the mechanisms and the limbs are synthesized correspondingly. Finally, several novel SLBM-type mechanisms are achieved by assembling the obtained limbs and selecting the actuated joints.

scholarly journals Type Synthesis of Two DOF Hybrid Translational Parallel Manipulators

2016 ◽  
Vol 836 ◽  
pp. 48-53 ◽  
Author(s):  
Latifah Nurahmi ◽  
Stéphane Caro
Keyword(s):  
Screw Theory ◽  
Synthesis Method ◽  
Parallel Manipulators ◽  
Degree Of Freedom ◽  
Type Synthesis ◽  
In Series ◽  
Actuation Scheme ◽  
Two Degree Of Freedom

This paper introduces a methodology for the type synthesis of two degree-of-freedom hybrid translational manipulators with identical legs. The type synthesis method is based upon the screw theory. Three types of two degree-of-freedom hybrid translational manipulators with identical legs are identified based upon their wrench decomposition. Each leg of the manipulators is composed of a proximal module and a distal module mounted in series. The assembly conditions and the validity of the actuation scheme are also defined. Eventually, some novel two degree-of-freedom hybrid translational manipulators are synthesized with the proposed procedure.

scholarly journals Research for a novel class of translational spatial multi-loop coupled mechanisms: Type synthesis and kinematic analysis

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879702 ◽  
Author(s):  
Shuang Zhang ◽  
Jingfang Liu ◽  
Huafeng Ding
Keyword(s):  
Kinematic Analysis ◽  
Degrees Of Freedom ◽  
Synthesis Method ◽  
Future Application ◽  
The Novel ◽  
Parallel Mechanisms ◽  
Type Synthesis ◽  
Split Method ◽  
New Synthesis ◽  
The Family

A novel type synthesis method for a class of spatial multi-loop coupled mechanisms with translational degrees of freedom is proposed in the paper. The novel class of spatial multi-loop coupled mechanisms has a stable topology layout which consists of three branches and three coupled chains. The basic idea of the new structural synthesis method lies at replacing the inputs of one mechanism by the outputs of another, thereby combining several mechanisms, where the topology split method for the topological layout and corresponding degree of freedom splitting principle are provided. The synthesis of the target mechanism is transformed into synthesis of corresponding serial and parallel mechanisms thereby, and a class of spatial multi-loop coupled mechanisms is synthesized. To validate the new synthesis method and to present a theoretical basis for future application, kinematic analysis of a single translational mobility (1T) spatial multi-loop coupled mechanism and a symmetrical two translational degrees of freedom (2T) spatial multi-loop coupled mechanism is performed. This article enriches the family of the spatial mechanisms for further instructing the study of spatial multi-loop coupled mechanisms.

Type Synthesis for Remote Center of Motion Mechanisms Based on Coupled Motion of Two Degrees-of-Freedom

2016 ◽  
Vol 138 (12) ◽  
Author(s):  
Yucheng He ◽  
Peng Zhang ◽  
Haiyang Jin ◽  
Ying Hu ◽  
Jianwei Zhang
Keyword(s):  
Minimally Invasive Surgery ◽  
Degrees Of Freedom ◽  
Synthesis Method ◽  
Type Synthesis ◽  
End Effector ◽  
Coupled Motion ◽  
New Family ◽  
Robot Systems ◽  
New Type ◽  
Application Prospects

Robots play an increasingly important role in the development of minimally invasive surgery (MIS). In MIS assistant robot systems, the remote center of motion (RCM) mechanism is a key component, and is the primary choice as end-effector for such systems. In this paper, first, we propose a new type of synthesis method for RCM mechanisms, which is based on the coupled motion of two DOFs to obtain new virtual center of motion (VCM) mechanisms, and then, through different combinations and configurations of VCM mechanisms, a new family of RCM mechanisms is achieved. Second, one of the obtained RCM mechanisms, which is deemed to have potential application prospects in MIS assistant robot, is investigated in detail, and a prototype is designed and fabricated to verify its feasibility. Finally, preliminary experiments are carried out on the prototype; the results show that, compared with existing ones, the new RCM mechanism's volume can be adjusted according to its required workspace, and it will be more compact when the required workspace is small. It will be an applicable option of end-effector for an MIS assistant robot.

scholarly journals Hydrothermal Synthesis and Structural Investigation of a Crystalline Uranyl Borosilicate

Inorganics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 25
Author(s):  
Kristen A. Pace ◽  
Vladislav V. Klepov ◽  
Mark D. Smith ◽  
Travis Williams ◽  
Gregory Morrison ◽  
...  
Keyword(s):  
Synthesis Method ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Exploratory Research ◽  
The Novel ◽  
Orthorhombic Space Group ◽  
Crystalline Materials ◽  
Waste Remediation ◽  
And Storage ◽  
X Ray Absorption

The relevance of multidimensional and porous crystalline materials to nuclear waste remediation and storage applications has motivated exploratory research focused on materials discovery of compounds, such as actinide mixed-oxoanion phases, which exhibit rich structural chemistry. The novel phase K1.8Na1.2[(UO2)BSi4O12] has been synthesized using hydrothermal methods, representing the first example of a uranyl borosilicate. The three-dimensional structure crystallizes in the orthorhombic space group Cmce with lattice parameters a = 15.5471(19) Å, b = 14.3403(17) Å, c = 11.7315(15) Å, and V = 2615.5(6) Å3, and is composed of UO6 octahedra linked by [BSi4O12]5− chains to form a [(UO2)BSi4O12]3− framework. The synthesis method, structure, results of Raman, IR, and X-ray absorption spectroscopy, and thermal stability are discussed.

Kinematic analysis and design of a novel 6-degree of freedom parallel robot

2014 ◽  
Vol 229 (2) ◽  
pp. 291-303 ◽  
Author(s):  
DU Hui ◽  
GAO Feng ◽  
PAN Yang
Keyword(s):  
Set Theory ◽  
Kinematic Analysis ◽  
Parallel Mechanism ◽  
Design Methodology ◽  
Parallel Robot ◽  
End Effector ◽  
Analysis And Design ◽  
Velocity Models ◽  
Reachable Workspace ◽  
Rotational Motions

A novel 3-UP3R parallel mechanism with six degree of freedoms is proposed in this paper. One most important advantage of this mechanism is that the three translational and three rotational motions are partially decoupled: the end-effector position is only determined by three inputs, while the rotational angles are relative to all six inputs. The design methodology via GF set theory is brought out, using which the limb type can be determined. The mobility of the end-effector is analyzed. After that, the kinematic and velocity models are formulated. Then, workspace is studied, and since the robot is partially decoupled, the reachable workspace is also the dexterous workspace. In the end, both local and global performances are discussed using conditioning indexes. The experiment of real prototype shows that this mechanism works well and may be applied in many fields.

scholarly journals Nonlinear Dynamics of a Vibratory Cone Crusher with Hysteretic Force and Clearances

2011 ◽  
Vol 18 (1-2) ◽  
pp. 3-12 ◽  
Author(s):  
Jing Jiang ◽  
Qing-Kai Han ◽  
Chao-Feng Li ◽  
Hong-Liang Yao ◽  
Shu-Ying Liu
Keyword(s):  
Nonlinear Dynamic Analysis ◽  
Deep Understanding ◽  
Degree Of Freedom ◽  
The Novel ◽  
Hysteretic Model ◽  
Dynamical Equations ◽  
Motion Patterns ◽  
Dynamical Behaviors ◽  
Cone Crusher ◽  
Two Degree Of Freedom

Based on the analysis on crushing process and hysteresis of material layers, a hysteretic model with symmetrical clearances is presented. The mechanical model of two-degree of freedom with bilinear hysteresis and its dynamical equations of system are proposed. In order to further investigate the dynamic characteristics of the novel vibratory cone crusher, the system is also simplified into a dynamical system of single degree of freedom with a bilinear hysteretic component together with clearances. According to some nonlinear dynamic analysis tools such as bifurcation diagram, Lyapunov exponents, Poincare section, etc., different motion patterns of the system are discussed, including periodic, periodic doubling, chaos and other characteristics. These theoretical results will provide readers with deep understanding on the regular and complex dynamical behaviors of the vibratory cone crusher due to the hysteresis with clearances.

scholarly journals On how the mechanochemical and co-precipitation synthesis method changes the sensitivity and operating range of the Ba2Mg1-xEuxWO6 optical thermometer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Quan T. H. Vu ◽  
Bartosz Bondzior ◽  
Dagmara Stefańska ◽  
Natalia Miniajluk-Gaweł ◽  
Maciej J. Winiarski ◽  
...  
Keyword(s):  
Density Functional ◽  
Synthesis Method ◽  
Double Perovskite ◽  
Relative Sensitivity ◽  
The Novel ◽  
Temperature Detection ◽  
The Density Functional Theory ◽  
Precision Temperature ◽  
Optical Thermometer ◽  
Co Precipitation

AbstractThe suitability of Ba2MgWO6 (BMW) double perovskite doped with Eu3+ for the construction of an optical thermometer was tested. It has been shown that by controlling the conditions of BMW synthesis, the sensitivity of the optical thermometer and the useful range of its work can be changed. Pure BMW and doped with Eu3+ samples were prepared using the mechano-chemical and co-precipitation methods. Both the absolute sensitivity and the relative sensitivity in relation to the synthesis route were estimated. The findings proved that the relative sensitivity can be modulated from 1.17%K−1 at 248 K, to 1.5%K−1 at 120 K for the co-precipitation and the mechanochemical samples, respectively. These spectacular results confirm the applicability of the Ba2MgWO6: Eu3+ for the novel luminescent sensors in high-precision temperature detection devices. The density-functional theory was applied to elucidate the origin of the host emission.

A Synthesis Method for Placing Workpieces in RPR Planar Robotic Workcells in Which Large Rotations Are Required at the Workpiece

1996 ◽  
Author(s):  
K. D. Chaney ◽  
J. K. Davidson
Keyword(s):  
Reference Frame ◽  
Synthesis Method ◽  
Analytical Representation ◽  
New Method ◽  
Two Dimensional ◽  
End Effector ◽  
Radial Location ◽  
Practical Applications ◽  
Full Turn ◽  
Large Rotations

Abstract A new method is developed for determining both a satisfactory location of a workpiece and a suitable mounting-angle of the tool for planar RPR robots that can provide dexterous workspace. The method is an analytical representation of the geometry of the robot and the task, and is particularly well suited to applications in which the task requires large rotations of the end-effector. It is determined that, when the task requires that the end-effector rotate a full turn at just two locations and when the first or third joint in the robot is rotatable by one turn, then the radial location of the workpiece is fixed in the workcell but its angular location is not fixed. When the mounting-angle of the tool is also a variable, the method accommodates tasks in which the tool must rotate a full turn at three locations on the workpiece. The results are presented as coordinates of points in a two-dimensional Cartesian reference frame attached to the workcell. Consequently, a technician or an engineer can determine the location for the workpiece by laying out these coordinates directly in the workcell. Example problems illustrate the method. Practical applications include welding and deposition of adhesives.

A New Approach to Type Synthesis of Spatial Robotic Mechanisms

1992 ◽  
Author(s):  
Akhtar N. Malik ◽  
D. R. Kerr
Keyword(s):  
Robot Manipulators ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Type Synthesis ◽  
End Effector ◽  
New Approach ◽  
Parallel Platform ◽  
Necessary And Sufficient

Abstract This paper presents a new approach for carrying out the type synthesis of spatial parallel platform-type mechanisms, used as robot manipulators. It takes into account the total mobility of the system and the partial mobility of its sub-mechanisms. The paper also provides the necessary and sufficient conditions for the mechanisms to function with specified end-effector freedoms, which are described in two theorems. The total number of possible mechanisms with given mobility and structure are tabulated. The work is based on a modified Grübler mobility criterion and also on the consideration of kinematic restraints.

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