Synthesis of a Rear Wheel Suspension Mechanism With Pure Rectilinear Motion

2009 ◽  
Vol 131 (10) ◽  
Author(s):  
Jing-Shan Zhao ◽  
Fulei Chu ◽  
Zhi-Jing Feng ◽  
Sheng Zhao
Keyword(s):  
Rigid Body ◽  
Screw Theory ◽  
Kinematic Chain ◽  
Rear Wheel ◽  
Rectilinear Motion ◽  
Rear Suspension ◽  
Kinematic Chains ◽  
Redundant Constraint ◽  
Straight Line ◽  
Suspension Structure

This paper focuses on the synthesis of an independent suspension that can guide the wheel to track a straight line when moving up (jounce) and down (rebound). With displacement subgroups, it first synthesizes a rigid body guidance mechanism and verifies the result through screw theory. To simplify and optimize the loads of each kinematic chain of the knuckle, it investigates the static equations and ultimately synthesizes a symmetric redundant-constraint suspension structure, which could not only eliminate the shambling shocks induced by the jumping of wheels but also decrease the abrasion of tires. Theoretically, only one pair of noncoplanar kinematic chains is necessary to realize straight line guidance. However, a second pair of noncoplanar kinematic chains is particularly utilized to improve the load status of the links. Because of the redundant constraints induced by the suspension structures, the whole weight can be significantly reduced compared with the initial one. ADAMS simulations with a set of real parameters indicate that the rear suspension mechanism proposed in this paper can guide the wheel to follow a rectilinear locus during jounce and rebound. Therefore, this kind of independent suspension can improve the ride and handling properties of advanced vehicles.

A Survey of One Class of 7-Jointed Serially Connected Robots: Type-Synthesis to Obtain Controllably Dexterous Workspace

1989 ◽  
Vol 111 (2) ◽  
pp. 163-175 ◽  
Author(s):  
J. K. Davidson
Keyword(s):  
Screw Theory ◽  
Kinematic Chain ◽  
Synthesis Process ◽  
Geometric Description ◽  
Type Synthesis ◽  
End Effector ◽  
Identification Process ◽  
Kinematic Chains ◽  
Five Axes

A type-synthesis process, which is based on screw theory and geometry, is developed to identify certain robots, each of which can provide controllably dexterous workspace of a tool-point. The identification process is confined to only those robots which control the motion of the end-effector with seven series-connected joints, the axes for the outermost three of which are concurrent. Forty six types of robots are so identified, and, for each, the results are (i) a suitable kinematic chain for the arm and (ii) suitable angle-dimensions for the links of the arm, where the angle-choices are limited to the values 0, ± π/2, and π. A geometric description of the dominant function for control is included. The same kinematic chains are surveyed for all possible parallel and right-angle arrangements of adjacent axes in the four links of the arm. Again utilizing screw theory, 160 robots are identified which do not posses full-cycle axis-dependence among some or all of the first five axes.

Identification of Isomorphism in Kinematic Chains Using Hamming Method

2014 ◽  
Vol 592-594 ◽  
pp. 2723-2727
Author(s):  
Indu Saini ◽  
Vijay Pal Singh
Keyword(s):  
Reliable Method ◽  
Kinematic Chain ◽  
Difficult Problem ◽  
Satisfactory Solution ◽  
Sewing Machine ◽  
Kinematic Chains ◽  
Straight Line ◽  
And Inversion ◽  
Isomorphism Identification

Isomorphism identification is a difficult problem in kinematic chains. There is number of method given by many researchers to detect the isomorphism and inversion of kinematic chain but each has its own shortcomings. Purpose of this paper is to give an efficient and reliable method. An attempt has been made to provide satisfactory solution to detection of isomorphism by using hamming method. The method is implemented on sewing machine, break drum; straight line motion mechanisms have six links kinematic chain.

Type Synthesis of 3-DOF Translational Parallel Manipulators Based on Screw Theory

2004 ◽  
Vol 126 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Xianwen Kong ◽  
Cle´ment M. Gosselin
Keyword(s):  
Screw Theory ◽  
General Procedure ◽  
Linear Equations ◽  
Kinematic Chain ◽  
Parallel Manipulators ◽  
Type Synthesis ◽  
Displacement Analysis ◽  
Kinematic Chains ◽  
Small Joint ◽  
Actuated Joints

A method is proposed for the type synthesis of 3-DOF (degree-of-freedom) translational parallel manipulators (TPMs) based on screw theory. The wrench systems of a translational parallel kinematic chain (TPKC) and its legs are first analyzed. A general procedure is then proposed for the type synthesis of TPMs. The type synthesis of legs for TPKCs, the type synthesis of TPKCs as well as the selection of actuated joints of TPMs are dealt with in sequence. An approach to derive the full-cycle mobility conditions for legs for TPKCs is proposed based on screw theory and the displacement analysis of serial kinematic chains undergoing small joint motions. In addition to the TPKCs proposed in the literature, TPKCs with inactive joints are synthesized. The phenomenon of dependent joint groups in a TPKC is revealed systematically. The validity condition of actuated joints of TPMs is also proposed. Finally, linear TPMs, which are TPMs whose forward displacement analysis can be performed by solving a set of linear equations, are also revealed.

Paradoxes in Rigid-Body Kinematics of Structures

1998 ◽  
Vol 65 (1) ◽  
pp. 218-222
Author(s):  
L. Mentrasti
Keyword(s):  
Rigid Body ◽  
Kinematic Analysis ◽  
Sufficient Conditions ◽  
Rigid Bodies ◽  
Rigid Body Motion ◽  
Body Motion ◽  
Kinematic Chains ◽  
Straight Line ◽  
Two Bodies

The paper discusses two paradoxes appearing in the kinematic analysis of interconnected rigid bodies: there are structures that formally satisfy the classical First and Second Theorem on kinematic chains, but do not have any motion. This can arise when some centers of instantaneous rotation (CIR) relevant to two bodies coincide with each other (first kind paradox) or when the CIRs relevant to three bodies lie on a straight line (second kind paradox). In these cases two sets of new theorems on the CIRs can be applied, pointing out sufficient conditions for the nonexistence of a rigid-body motion. The question is clarified by applying the presented theory to several examples.

Mobility Analysis of Parallel Mechanisms Based on Screw Theory and the Concept of Equivalent Serial Kinematic Chain

2005 ◽  
Author(s):  
Xianwen Kong ◽  
Cle´ment M. Gosselin
Keyword(s):  
Systematic Approach ◽  
Screw Theory ◽  
Kinematic Chain ◽  
Second Step ◽  
Parallel Mechanisms ◽  
Mobility Analysis ◽  
Single Loop ◽  
Kinematic Chains ◽  
Serial Chain ◽  
Parallel Kinematic

This paper presents a systematic approach for the mobility analysis of parallel mechanisms. The method is based on screw theory and the concept of equivalent serial chain. An equivalent serial kinematic chain of a k-legged PKC (parallel kinematic chain) is defined as a serial kinematic chain which has the same twist system and the wrench system as the k-legged PKC. Using the proposed approach, the mobility analysis of a PKC is performed in two steps. The first step is the instantaneous mobility analysis, and the second step is the full-cycle mobility inspection. The first step is dealt with based on screw theory. The second step is performed with the aid of the concept of equivalent serial chain and the types of multi-DOF overconstrained single-loop kinematic chains. The proposed approach is illustrated with several examples.

Complementarity Relationships and Critical Configurations in Rigid-Body Collisions of Planar Kinematic Chains With Smooth External Contacts

2020 ◽  
Vol 87 (12) ◽  
Author(s):  
Yildirim Hurmuzlu
Keyword(s):  
Rigid Body ◽  
Special Class ◽  
Solution Method ◽  
External Surface ◽  
Kinematic Chain ◽  
Impulse Wave ◽  
Kinematic Chains ◽  
Complementarity Conditions ◽  
Critical Configurations

Abstract In this article, we consider a special class of collision problems that are frequently encountered in the field of robotics. Such problems can be described as a kinematic chain with one of its ends striking an external surface, while the remaining ends resting on other surfaces. This type of problem involves complementarity relationships between the normal velocities and impulses at the contacting ends. We present a solution method that takes into account the complementarity conditions at the contacting ends. In addition, we study the critical configurations of particle and rigid-body chains where the impulse wave generated by impact gets blocked before it reaches a contacting end.

Synthesis of Rectilinear Motion Generating Spatial Mechanism With Application to Automotive Suspension

2008 ◽  
Vol 130 (6) ◽  
Author(s):  
Jing-Shan Zhao ◽  
Fulei Chu ◽  
Zhi-Jing Feng
Keyword(s):  
Synthesis Method ◽  
Rectilinear Motion ◽  
End Effector ◽  
Kinematic Chains ◽  
Spatial Mechanism ◽  
Straight Line ◽  
Automotive Suspension ◽  
Generic Process ◽  
Wheel Track

This paper proposes a synthesis method for rectilinear motion generating spatial mechanism with application to automotive suspension. First, it presents a generic process to synthesize the kinematic chains of a mechanism with the prescribed mobility, and then it deduces the construction criteria of feasible kinematic chains for such a mechanism. The most outstanding advantages of the rectilinear motion generating spatial mechanism used as the independent automotive suspension are that the orientation and position parameters such as kingpin, caster, camber, axis distance, and wheel track are always maintained constant during jounce and rebound. These ideal characteristics are guaranteed by the particular rigid guidance mechanism whose end effector only has one translation along an exact straight line.

scholarly journals Virtual and Physical Prototyping of Reconfigurable Parallel Mechanisms with Single Actuation

2021 ◽  
Vol 11 (15) ◽  
pp. 7158
Author(s):  
Alexey Fomin ◽  
Daniil Petelin ◽  
Anton Antonov ◽  
Victor Glazunov ◽  
Marco Ceccarelli
Keyword(s):  
Computer Aided Design ◽  
Screw Theory ◽  
Complex Geometry ◽  
Kinematic Chain ◽  
Parallel Mechanisms ◽  
Mobility Analysis ◽  
Kinematic Chains ◽  
Physical Prototype ◽  
Detailed Computer ◽  
Aided Design

The paper presents novel models of reconfigurable parallel mechanisms (RPMs) with a single active degree-of-freedom (1-DOF). The mechanisms contain three to six identical kinematic chains, which provide three (for the tripod) to zero (for the hexapod) uncontrollable DOFs. Screw theory is applied to carry out mobility analysis and proves the existence of controllable and uncontrollable DOFs of these mechanisms. Each kinematic chain in the synthesized mechanisms consists of planar and spatial parts. Such a design provides them with reconfiguration capabilities even when the driving link is fixed. This allows reproduction of diverse output trajectories without using additional actuators. In this paper, the model of a mechanism with six kinematic chains (hexapod) has been virtually and physically prototyped. The designing and assembling algorithms are developed using the detailed computer-aided design (CAD) model, which was further used to carry out kinetostatic analysis considering complex geometry of mechanism elements and friction among all contacting surfaces of joints. The developed virtual prototype and its calculation data have been further applied to fabricate mechanism elements and assemble an actuated full-scale physical prototype for future testing.

A Class of Symmetrical 3T, 3T-1R, and 3R Mechanisms With Parallel Linear Motion Elements

2018 ◽  
Vol 10 (5) ◽  
Author(s):  
Yi Yang ◽  
Wuxiang Zhang ◽  
Huayan Pu ◽  
Yan Peng
Keyword(s):  
Rotational Motion ◽  
Screw Theory ◽  
Translational Motion ◽  
Kinematic Chain ◽  
Linear Motion ◽  
Kinematic Chains ◽  
Lower Mobility ◽  
Kinematic Performance ◽  
Linear Actuators ◽  
First Time

A kind of kinematic chain with parallel linear motion elements (PLMEs) is proposed and studied in this paper. Based on screw theory, the kinematic screw equations of these linkages are established. The two special categories of PLMEs, with pure translational motion and with pure rotational motion respectively, are identified. The mobilities and the singularities of these kinematic chains are also investigated. By the utilization of these PLMEs, three types of the compound limbs are invented and analyzed. Through assembling these compound limbs in different ways, a class of lower mobility symmetrical 3T, 3T-1R, and 3R mechanisms is synthesized and presented for the first time. The simplified kinematic equations for this class of mechanisms driven by the linear actuators are derived. And the workspaces, singularities, and kinematic performance are addressed. Finally, three typical prototypes with regard to 3T, 3T-1R, and 3R mechanisms are manufactured and experimented to validate the mobility and motion feasibility of these mechanisms.

Sir Robert Stawell Ball and methodologies of modern screw theory

2002 ◽  
Vol 216 (1) ◽  
pp. 1-11 ◽  
Author(s):  
H Lipkin ◽  
J Duffy
Keyword(s):  
Computational Geometry ◽  
Rigid Body ◽  
Lie Algebra ◽  
Screw Theory ◽  
Mechanical Design ◽  
Ball Screw ◽  
Dual Numbers ◽  
Body Dynamics ◽  
Rigid Body Mechanics ◽  
Multi Body

The theory of screws was largely developed by Sir Robert Stawell Ball over 100 years ago to investigate general problems in rigid body mechanics. Nowadays, screw theory is applied in many different but related forms including dual numbers, Plilcker coordinates and Lie algebra. An overview of these methodologies is presented along with a perspective on Ball. Screw theory has re-emerged after a hiatus to become an important tool in robot mechanics, mechanical design, computational geometry and multi-body dynamics.

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