Stiffness Analysis and Experimental Validation for the 6-Dof Jaw Opening-Closing Training Parallel Robot WY-5 (Waseda Yamanashi 5)

2004 ◽  
Vol 16 (6) ◽  
pp. 570-578
Author(s):  
Giuseppe Carbone ◽  
◽  
Hideaki Takanobu ◽  
Marco Ceccarelli ◽  
Atsuo Takanishi ◽  
...  
Keyword(s):  
Stiffness Matrix ◽  
Experimental Validation ◽  
Mouth Opening ◽  
Experimental Tests ◽  
Parallel Robot ◽  
Stiffness Analysis ◽  
Jaw Opening ◽  
Proposed Model ◽  
Stiffness Characteristics ◽  
Opening And Closing

In this paper a mouth opening and closing training robot named as WY-5 (Waseda Yamanashi version 5) is analyzed in terms of stiffness characteristics. Basic models and a formulation are proposed in order to deduce the stiffness matrix as a function of the most important stiffness parameters of the WY-5 architecture. A numerical simulation is carried out as based on the proposed formulation. Experimental tests are carried out in order to validate the proposed model that can be used for design/control purposes in order to improve the performance of WY-5.

Static Stiffness Analysis and Simulation of 6-PTRT Parallel Robot

2013 ◽  
Vol 318 ◽  
pp. 33-38
Author(s):  
De Long Leng ◽  
Dong Sheng Qu ◽  
Yan Wu Liu
Keyword(s):  
Parallel Robot ◽  
Initial Position ◽  
Influence Coefficient ◽  
Static Stiffness ◽  
Stiffness Analysis ◽  
Proposed Model ◽  
Stiffness Model ◽  
Influence Coefficient Method ◽  
Stiffness Characteristics ◽  
Stiffness Distribution

To reveal the static stiffness behavior of a 6-PTRT parallel robot and find out its change rule in order to provide the reasonable parameters for the structural design, the stiffness characteristics of this parallel mechanism was studied. Based on the influence coefficient method, a static stiffness model for 6-PTRT parallel robot was established. The proposed model considered not only the axis stiffness of actuator but also the stiffness of passive joints, and the change of Jacobian matrix and first-order influence coefficient brought about by tiny change of the parallel robot mechanism's configuration under external wrench. The static stiffness matrix of parallel robot in initial position and its stiffness distribution rules for a certain workspace were given by numerical calculation and finite element method, which comparatively verify the exactness of stiffness model.

Study of the Stiffness Matrix of Preloaded Duplex Angular Contact Ball Bearings

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Shengye Lin ◽  
Shuyun Jiang
Keyword(s):  
Stiffness Matrix ◽  
Degrees Of Freedom ◽  
Ball Bearing ◽  
Ball Bearings ◽  
Fixed Position ◽  
Angular Contact Ball Bearing ◽  
Face To Face ◽  
Radial Stiffness ◽  
Proposed Model ◽  
Stiffness Characteristics

This paper studies the stiffness characteristics of preloaded duplex angular contact ball bearings. First, a five degrees-of-freedom (5DOF) quasi-static model of the preloaded duplex angular contact ball bearing is established based on the Jones bearing model. Three bearing configurations (face-to-face, back-to-back, and tandem arrangements) and two preload mechanisms (constant pressure preload and fixed position preload) are included in the proposed model. Subsequently, the five-dimensional stiffness matrix of the preloaded duplex angular contact ball bearing is derived analytically. Then, an experimental setup is developed to measure the radial stiffness and the angular stiffness of duplex angular contact ball bearings. The simulated results match well with those from experiments, which prove the validity of the proposed model. Finally, the effects of bearing configuration, preload mechanism, and unloaded contact angle on the angular stiffness and the cross-coupling are studied systematically.

A stiffness analysis for a hybrid parallel-serial manipulator

Robotica ◽  
2004 ◽  
Vol 22 (5) ◽  
pp. 567-576 ◽  
Author(s):  
Giuseppe Carbone ◽  
Marco Ceccarelli
Keyword(s):  
Numerical Investigation ◽  
Performance Index ◽  
Stiffness Matrix ◽  
Mechanical Design ◽  
General Procedure ◽  
Design Parameters ◽  
Serial Manipulators ◽  
Stiffness Analysis ◽  
Hybrid Manipulator ◽  
Stiffness Characteristics

In this paper a hybrid parallel-serial manipulator, named as CaHyMan (Cassino Hybrid Manipulator), is analyzed in term of stiffness characteristics as a specific example of a general procedure for analyzing stiffness of parallel-serial manipulators. A formulation is presented to deduce the stiffness matrix as a function of the most important stiffness and design parameters of the mechanical design. A formulation is proposed for a stiffness performance index by using the obtained stiffness matrix. A numerical investigation has been carried out on the effects of design parameters and fundamental results are discussed in the paper.

Stiffness Analysis of 3-RPR Planar Parallel Mechanism to the Stiffness Control

2009 ◽  
Vol 16-19 ◽  
pp. 786-790 ◽  
Author(s):  
Shu Jun Li ◽  
Clément Gosselin
Keyword(s):  
Stiffness Matrix ◽  
Parallel Mechanism ◽  
Stiffness Analysis ◽  
Numerical Examples ◽  
Stiffness Control ◽  
Conservative Congruence Transformation ◽  
Stiffness Characteristics ◽  
External Forces ◽  
Congruence Transformation

The analytical stiffness equations of the 3-RPR planar parallel mechanism are derived in this paper based on the Conservative Congruence Transformation (CCT) stiffness matrix proposed in [1-3]. Stiffness maps of the 3-RPR mechanism are plotted in order to show the behaviour of the stiffness with and without external forces. The stiffness characteristics of the mechanism are analyzed and discussed in details. Numerical examples show that the stiffness in x and in y are well balanced, while the stiffness in tends to be lower.

scholarly journals Theoretical modeling of the vertical stiffness of a rolling lobe air spring

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042094089
Author(s):  
Liufeng Xu
Keyword(s):  
Analytical Model ◽  
Ride Comfort ◽  
Experimental Tests ◽  
Geometric Parameters ◽  
Air Spring ◽  
Vertical Stiffness ◽  
Approximate Analytic Method ◽  
Proposed Model ◽  
Stiffness Characteristics ◽  
The Relationship

In order to study the characteristics of a rolling lobe air spring, a vertical stiffness analytical model is constructed based on thermodynamics and hydrodynamics. The merit of this vertical stiffness analytical model is that an analytical solution of geometric parameters is obtained by an approximate analytic method. Meanwhile, experimental tests are carried out to verify the accuracy of the vertical stiffness analytical model. The vertical stiffness analytical model can be used to qualitatively analyze the influence of geometric parameters on the vertical stiffness characteristics of a rolling lobe air spring. Therefore, the relationship between geometric parameters and the vertical stiffness characteristics is analyzed based on the proposed model. The conclusions show that the vertical stiffness analytical model can well predict the mechanical characteristics of a rolling lobe air spring and provide guidance for parameter design and vehicle ride comfort improvement.

Stiffness Analysis for a Novel Parallel-Robot Based High-Precision Flexible Assembly Fixture

2007 ◽  
Vol 364-366 ◽  
pp. 327-332 ◽  
Author(s):  
Hong Jian Yu ◽  
Bing Li ◽  
Xiao Jun Yang ◽  
Ying Hu ◽  
Hong Hu
Keyword(s):  
Stiffness Matrix ◽  
Screw Theory ◽  
System Modeling ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Stiffness Analysis ◽  
Flexible Assembly ◽  
Global Stiffness Matrix ◽  
The Relationship ◽  
Assembly Fixture

In this paper, a novel parallel mechanism (3-RRRS/UPR) used in flexible fixture with configuration composed of two parallel robots (2-RR and 3-RRRS/ UPR) is presented. First, system modeling including the mobility study is conducted. Then a novel methodology is proposed that makes use of screw theory to analyze the deformation and stiffness of the mechanism: firstly we identified the existence of the deformation of the subchain, in terms of the relationship between the effective screw and deformation screw; then we took the deformation as an infinitesimal motion of the mechanism, and the stiffness matrix corresponding to the deformation can be deduced. Finally the global stiffness matrix of the whole mechanism is modeled by assembling different stiffness characters based on the presented methodology.

scholarly journals A Clinical Jaw Movement Training Robot for Mouth Opening/Closing and Lateral Movement Training

2004 ◽  
Vol 16 (6) ◽  
pp. 579-586 ◽  
Author(s):  
Akihisa Okino ◽  
◽  
Hideaki Takanobu ◽  
Atsuo Takanishi ◽  
Kayoko Ohtsuki ◽  
...  
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Mouth Opening ◽  
Lateral Movement ◽  
Jaw Movement ◽  
Movement Training ◽  
Temporomandibular Joints ◽  
Jaw Opening ◽  
Opening And Closing ◽  
Mandibular Joints

This paper discusses a jaw movement training robot implementing a 6-DOF (degrees of freedom) parallel mechanism, and its application to mouth opening and closing and lateral movement training. Temporomandibular joints (TMJ) syndrome prevents patients from opening their mouths or moving their jaws easily due to problems with mandibular joints, mastication muscles, and other organs involved in food chewing. Conventional therapy involves simple mouth opening apparatuses, although individual techniques vary with the physician. We developed and improved a jaw movement training robot that aids jaw opening and closing and lateral jaw movement training. This system consists of a 6-DOF slave manipulator representing a patient manipulator and a 2-DOF or 3-DOF master manipulator representing the doctor command manipulator.

scholarly journals Jaw movement during the speech in children with allergic rhinitis

CoDAS ◽  
2015 ◽  
Vol 27 (4) ◽  
pp. 359-364 ◽  
Author(s):  
Sandro Júnior Henrique Lima ◽  
Leandro de Araújo Pernambuco ◽  
Aline de Lima Lins ◽  
Lucas Carvalho Aragão Albuquerque ◽  
Hilton Justino da Silva
Keyword(s):  
Allergic Rhinitis ◽  
Mouth Opening ◽  
Nonparametric Tests ◽  
Descriptive Statistics ◽  
University Hospital ◽  
Spearman Correlation ◽  
Jaw Movements ◽  
Jaw Opening ◽  
Significant Difference ◽  
Opening And Closing

INTRODUCTION: Allergic rhinitis can cause changes in stomatognathic functions, which may alter the mandibular dynamics. Electrognathography is used in the recording of jaw movements, making it valid for analysis of movements in speech.PURPOSE: To characterize the amplitude and velocity of jaw movements during speech in children with and without allergic rhinitis.METHODS: The sample consisted of 32 children aged 7-12 years, treated at a university hospital, divided into two groups: one with rhinitis and the other without rhinitis. To capture the jaw movements during speech, we used an electrognathography with the aid of a list of phonetically balanced figures. For the analysis of data, we used, in addition to descriptive statistics, nonparametric tests, Spearman correlation coefficient and the Mann-Whitney test, with a significant value of p=0.05.RESULTS: No significant difference was observed in jaw movements between groups, with values of p equals to 0.175, 0.650, and 0.462 for amplitude and jaw opening and closing velocity, respectively. However, a strong correlation was observed between the variables velocity and amplitude of mouth opening, being slightly higher in the group of children with allergic rhinitis.CONCLUSION: The amplitude and velocity of jaw movements are found to be similar in children with and without allergic rhinitis, and a correlation exits between these variables. In addition, they were more heterogeneous in the group without allergic rhinitis.

Stiffness analysis and experimental validation of modular-type hybrid antagonistic tendon-driven joint systems

Robotica ◽  
2018 ◽  
Vol 36 (11) ◽  
pp. 1680-1700 ◽  
Author(s):  
Hyunhwan Jeong ◽  
Bongki Kang ◽  
Joono Cheong
Keyword(s):  
Mathematical Analysis ◽  
Potential Benefit ◽  
Experimental Validation ◽  
Needle Insertion ◽  
Experimental Results ◽  
Stiffness Analysis ◽  
Tendon Length ◽  
Stiffness Model ◽  
Stiffness Characteristics ◽  
Detailed Mathematical Analysis

SUMMARYThis paper proposes a new antagonistic tendon-driven joint (TDJ) that exhibits higher stiffness and larger travel range than conventional types of TDJs. A detailed mathematical analysis of the stiffness of the proposed TDJ is conducted and compared to other TDJs. The effect of the tendon length is taken into consideration to establish a more precise and realistic stiffness model of the proposed TDJ. Thereafter, two hardware prototypes of the proposed TDJ design, developed in the form of a packaged modular structure that integrates two TDJs, are introduced. Using these prototypes, the stiffness characteristics of the proposed TDJs are verified through experimentation. Additionally, experimental results on the stiffness behavior during the mimicked needle insertion tasks are provided. Results show that the proposed TDJs present much higher stiffness than conventional ones and thus give a potential benefit to precision manipulation.

Sign in / Sign up

Export Citation Format

Share Document