SCREW THEORY BASED METHOD OF KINEMATIC ANALYSIS ON TANDEM ROBOTS OF CLOSED CHAINS

Abstract High trafficability and stability are the most two significant features of the forestry chassis. In this study, in order to improve surface trafficability, a novel articulated wheel-legged forestry chassis(AWLFC) is presented. To balance the trafficability and stability, a serial suspension system which is a combination with the active four-bar linkage articulated suspension (AFLAS) and passive V shape rocker-bogie is proposed. Then, parameter optimization with a comprehensive object function is implemented not only to enhance the trafficability and stability benefit of the structure but also to reduce the wheel slip. After that, through the flexible kinematic model based on screw theory, characteristics such as leveling ability and surface profile accessibility of the chassis are analyzed. The minimum accessible radius is obtained as 3088mm, and the longitudinal and lateral leveling angle reaches to 22° and 28.7° separately. The new chassis performs better on leveling ability and surface profile accessibility than the forestry chassis in the current literature. Finally, compared with the simulation and prototype experiment, error rates of the flexible kinematic analysis are reduced by 12.2% and 8.6% related to the rigid model. Previously inaccessible forestry working environments can be available with the development of AWLFC.

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Geometry Modeling for Indexing Cams Based on Screw Theory and Product of Exponential Formula

Materials Science Forum ◽

10.4028/www.scientific.net/msf.505-507.991 ◽

2006 ◽

Vol 505-507 ◽

pp. 991-996

Author(s):

Zong Yu Chang ◽

Yu Hu Yang ◽

Ce Zhang ◽

Shou Bin Ding ◽

Bin Zhang ◽

...

Keyword(s):

Kinematic Analysis ◽

Screw Theory ◽

Product Formula ◽

Coordinate Systems ◽

Model Surface ◽

Cam Mechanism ◽

Geometry Modeling ◽

Exponential Formula ◽

Indexing Mechanism ◽

Systems Transformation

This paper proposes a method of geometry modeling for indexing cam mechanism by using screw theory and exponential product formula. Kinematic analysis based on screw theory is introduced firstly. Then, method to model surface of indexing cams is presented when screw theory and exponential product formula are applied. The paper gives examples to obtain the geometry models of roller gear cam, barrel indexing cam and parallel indexing cam. Our work suggests that this method can avoid the burdensome work on building coordinate systems, transformation matrixes and understanding on the mechanism. Moreover, this method can be used to innovate and design new types of indexing mechanism.

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Kinematic Analysis of a Novel Manual Medical Instrument for Minimally Invasive Surgery

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.308-310.1969 ◽

2011 ◽

Vol 308-310 ◽

pp. 1969-1974 ◽

Cited By ~ 2

Author(s):

Xiao Fei Wang ◽

Jian Min Li ◽

Guo Kai Zhang

Keyword(s):

Minimally Invasive Surgery ◽

Minimally Invasive ◽

Invasive Surgery ◽

Kinematic Analysis ◽

Screw Theory ◽

Medical Instrument ◽

Low Friction ◽

Calculation Results ◽

High Flexibility ◽

Basic Configuration

This paper presents a novel compact manual instrument for minimally invasive surgery (MIS). The instrument possesses several good features, such as large workspace, high flexibility, low friction and comfortable operability. The structure of the instrument is a basic configuration of some manual instruments. Besides basic operations, it can be applied to accomplish some more difficult processes, e.g. suturing and knotting. Based on screw theory and product-of-exponentials (POE) formula, the degree of freedom (DoF) and kinematics of the instrument are analyzed in the paper. The calculation results are verified by the simulation.

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Kinematics and mobility analysis of carton folds in packing manipulation based on the mechanism equivalent

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/095440602760400931 ◽

2002 ◽

Vol 216 (10) ◽

pp. 959-970 ◽

Cited By ~ 43

Author(s):

J S Dai ◽

J Rees Jones

Keyword(s):

Graph Theory ◽

Closed Form ◽

Kinematic Analysis ◽

Degrees Of Freedom ◽

Screw Theory ◽

Mobility Analysis ◽

Mathematical Basis ◽

Packaging Process ◽

Kinematic Geometry ◽

Position And Orientation

The process of erecting and closing a carton in packing manipulation is seen as a succession of folds in position and orientation from one distinct configuration to another. Permitted manipulations and changes in shape are governed by the geometry of crease lines, dimensions and profiles of the panels. The possibility for panels to fold into successive distinct configurations is determined by the kinematic geometry. This paper presents a mathematical basis which determines the mobility of distinct configurations of a carton to include the degrees of freedom dominating the manipulation and the overconstraint configurations in an erected and closed form, and proposes the kinematic analysis of a carton during packing manipulation. Use is made of the concept of line vectors and screw theory associated with graph theory. The analysis helps to explain some configurations which show how a carton can fold and opens up the way of describing manipulation in the packaging process.

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Kinematic Analysis and Simulation of the Tri-Prism Deployable Structure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.799-800.1183 ◽

2015 ◽

Vol 799-800 ◽

pp. 1183-1187

Author(s):

Huai Dong Zhou ◽

Peng Zhen ◽

Wu Sheng Chou

Keyword(s):

Kinematic Analysis ◽

Screw Theory ◽

Mechanical Design ◽

Complex Mechanism ◽

Drive Mode ◽

Kinematic Equation ◽

Deployable Structure ◽

In Series ◽

The Relationship ◽

Theoretical Results

The Tri-prism deployable structure is a complex mechanism which consists of six deployable structure units in series. All deployable structure units have the similar movements; the screw theory is used to establish the kinematic equation of each unit and the entire tri-prism deployable structure. Meanwhile, the motion stability, drive mode and mechanical design of the tri-prism deployable structure have been comprehensively researched. Finally, extensive simulations in ADAMS have been conducted to obtain the relationship between the motions of ends and inputs, which are further compared with theoretical results.

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Design and Kinematic Analysis of a 3RRlS Metamorphic Parallel Mechanism for Large-Scale Reconfigurable Space Multifingered Hand

Journal of Mechanisms and Robotics ◽

10.1115/1.4040356 ◽

2018 ◽

Vol 10 (4) ◽

Cited By ~ 13

Author(s):

Chong Zhao ◽

Hongwei Guo ◽

Rongqiang Liu ◽

Zongquan Deng ◽

Bing Li

Keyword(s):

Shape Memory Alloy ◽

Kinematic Analysis ◽

Parallel Mechanism ◽

Large Scale ◽

Screw Theory ◽

Kinematic Equation ◽

Aerospace Application ◽

Parasitic Motion ◽

Geometric Conditions ◽

In Series

Capturing noncooperative targets in space has great prospects for aerospace application. In this work, the knuckle unit of a large-scale reconfigurable space multifingered hand (LSRSMFH) for multitask requirements is studied. A plurality of knuckle units is connected in series to form a finger of the LSRSMFH. First, the lockable spherical (lS) joint, a new metamorphic joint that can function as a Hooke (lS1) or spherical (lS2) joint and is driven by shape memory alloy (SMA) material, is proposed. Based on the lS joint, this paper presents a new metamorphic parallel mechanism (MPM) (i.e., 3RRlS MPM), which has four configurations, namely, 3RRlS1, 3RRlS2, 2RRlS1-RRlS2, and 2RRlS2-RRlS1 configuration. The degree-of-freedom (DOF), overconstraint, and parasitic motion of the 3RRlS MPM are analyzed using screw theory, of which the DOF can be changed from 1 to 3. The 3RRlS1 configuration has a virtual constraint, and the 3RRlS2 configuration has parasitic motions. The results indicate that the mechanism motion screws can qualitatively represent the mechanism parasitic motions, and it is verified by deriving the kinematic equation of the 3RRlS MPM based on its spatial geometric conditions, the workspace of the 3RRlS MPM is further solved. The kinematic analysis indicates that the 3RRlS MPM can realize the folding, capturing, and reconfiguring conditions of the LSRSMFH.

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Kinematics and Friction in Grasping by Robotic Hands

Journal of Mechanisms Transmissions and Automation in Design ◽

10.1115/1.3258809 ◽

1987 ◽

Vol 109 (3) ◽

pp. 398-404 ◽

Cited By ~ 15

Author(s):

E. N. Ohwovoriole

Keyword(s):

Rigid Body ◽

Kinematic Analysis ◽

Screw Theory ◽

Robotic Hands ◽

Kinematic Theory ◽

Novel Method ◽

Total Freedom ◽

The Stability

Using the extended screw theory, grasping is analyzed in terms of the complete and partial constraint of a rigid body. The underlying kinematic theory is first reviewed and illustrated. The extended screw theory is then used to determine the disturbing and nondisturbing external wrenches, and resulting disturbances for a grasped object. This is a new application of the concept of total freedom based on the idea of component motions and the wrenches that can cause them. Determining the disturbing and nondisturbing wrenches is tantamount to determining the stability of the grasp in regard to total freedom. Finally, a novel method of incorporating friction in the kinematic analysis of grasping using screw theory is also developed using the concepts of apparent normals and apparent motions.

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