Dynamic Trajectory Planning and Geometric Analysis of a Two-Degree-of-Freedom Translational Cable-Suspended Planar Parallel Robot Using a Parallelogram Cable Loop

2019 ◽  
Vol 11 (2) ◽  
Author(s):  
Jordan M. Longval ◽  
Clément Gosselin
Keyword(s):  
Trajectory Planning ◽  
Geometric Analysis ◽  
Parallel Robot ◽  
Design Parameters ◽  
Sensitivity Index ◽  
General Elliptic ◽  
Planning Approach ◽  
Kinematic Sensitivity ◽  
Two Degree Of Freedom ◽  
Dynamic Trajectory

This paper presents a trajectory planning approach and an analysis of the geometric design parameters for a planar cable-suspended translational parallel robot based on a parallelogram cable loop. The cable robot produces purely translational movements in a planar workspace. Furthermore, this special architecture only requires two actuators, which make it fully actuated. From the dynamic model of the robot, general algebraic inequalities are obtained that ensure that the cables remain taut. A general elliptic trajectory is then defined and substituted into the algebraic inequalities to obtain conditions on the geometrical design parameters that ensure that the cables are always in tension. In addition, a special trajectory-specific oscillation frequency emerges and enables the end effector to dynamically move beyond the boundaries of the static workspace, thus expanding the workspace of the mechanism. Finally, a kinematic sensitivity index is studied in order to determine if the parallelogram structure has any influence on the rotational sensitivity of the mechanism.

Dynamic Trajectory Planning and Geometric Design of a Two-DOF Translational Cable-Suspended Planar Parallel Robot Using a Parallelogram Cable Loop

2018 ◽  
Author(s):  
Jordan M. Longval ◽  
Clément Gosselin
Keyword(s):  
Trajectory Planning ◽  
Parallel Robot ◽  
Geometric Design ◽  
Rotational Stability ◽  
Design Parameters ◽  
Sensitivity Index ◽  
General Elliptic ◽  
Planning Approach ◽  
Kinematic Sensitivity ◽  
Dynamic Trajectory

This paper presents a trajectory planning approach and an analysis of the geometric design parameters for a planar cable-suspended translational parallel robot based on a parallelogram cable loop. The cable robot produces purely translational movements in a planar workspace. Furthermore, this special architecture only requires two actuators which makes it fully actuated. From the dynamic model of the robot, general algebraic inequalities are obtained that ensure that the cables remain taut. A general elliptic trajectory is then defined and substituted into the algebraic inequalities to obtain conditions on the geometrical design parameters that ensure that the cables are always in tension. In addition, a special trajectory-specific oscillation frequency emerges and enables the end-effector to dynamically move beyond the boundaries of the static workspace, thus expanding the workspace of the mechanism. Finally, a kinematic sensitivity index is studied in order to assess the influence of the parallelogram structure on the rotational stability of the mechanism.

GEOMETRIC ANALYSIS OF THE KINEMATIC SENSITIVITY OF PLANAR PARALLEL MECHANISMS

2011 ◽  
Vol 35 (4) ◽  
pp. 477-490 ◽  
Author(s):  
Mohammad Hossein Saadatzi ◽  
Mehdi Tale Masouleh ◽  
Hamid D. Taghirad ◽  
Clément Gosselin ◽  
Philippe Cardou
Keyword(s):  
Physical Meaning ◽  
Performance Index ◽  
Geometric Analysis ◽  
Geometric Approach ◽  
Sensitivity Index ◽  
Parallel Mechanisms ◽  
Dimensional Synthesis ◽  
Kinematic Sensitivity

The kinematic sensitivity is a unit-consistent measure that has been recently proposed as a mechanism performance index to compare robot architectures. This paper presents a robust geometric approach for computing this index for the case of planar parallel mechanisms. The physical meaning of the kinematic sensitivity is investigated through different combinations of the Euclidean and infinity norms and by means of several illustrative examples. Finally, this paper opens some avenues to the dimensional synthesis of parallel mechanisms by exploring the meaning of the global kinematic sensitivity index.

Optimal Synthesis of a Planar Reactionless Three-Degree-of-Freedom Parallel Mechanism

2010 ◽  
Author(s):  
Jean-Francois Collard ◽  
Cle´ment Gosselin
Keyword(s):  
Power Consumption ◽  
Interesting Property ◽  
Degree Of Freedom ◽  
Design Parameters ◽  
Sensitivity Index ◽  
Optimization Approach ◽  
Counter Rotation ◽  
Kinematic Sensitivity ◽  
Global Moment ◽  
Three Degree Of Freedom

A reactionless mechanism is one in which no reaction forces nor moments are transmitted to the base for any arbitrary motion. This interesting property often requires to increase the total mass and the moments of inertia, leading to reduced dynamical performances. Therefore, this paper presents an optimization approach to synthesize and improve the dynamical performance of a reactionless three-degree-of-freedom planar mechanism. The three legs of this original mechanism are composed of reactionless four-bar mechanisms dynamically balanced with only one counter-rotation at the base. The optimization variables are the geometric and inertial parameters, while the goal is to minimize the global moment of inertia of each leg. This will reduce the power consumption of the three actuators and increase the agility. To meet physical and realistic requirements, the optimization problem is also constrained with bounds on the parameters, with the reachability of a given workspace and with a given range on a kinematic sensitivity index. Since different initial guesses of the optimization lead to similar objective results, it is proposed to search for several local solutions (morphologies) in the design space. The final choice among these solutions is made using additional design criteria based on the sensitivity in terms of dynamic balancing and power consumption with respect to the design parameters.

Optimal Synthesis of a Planar Reactionless Three-Degree-of-Freedom Parallel Mechanism

2011 ◽  
Vol 3 (4) ◽  
Author(s):  
Jean-François Collard ◽  
Clément Gosselin
Keyword(s):  
Power Consumption ◽  
Interesting Property ◽  
Degree Of Freedom ◽  
Design Parameters ◽  
Sensitivity Index ◽  
Optimization Approach ◽  
Counter Rotation ◽  
Kinematic Sensitivity ◽  
Global Moment ◽  
Three Degree Of Freedom

A reactionless mechanism is one in which no reaction forces nor moments are transmitted to the base for any arbitrary motion. This interesting property often requires to increase the total mass and the moments of inertia, leading to reduced dynamical performances. Therefore, this paper presents an optimization approach to synthesize and improve the dynamical performance of a reactionless three-degree-of-freedom planar mechanism. The three legs of this original mechanism are composed of reactionless four-bar mechanisms dynamically balanced with only one counter-rotation at the base. The optimization variables are the geometric and inertial parameters, whereas the goal is to minimize the global moment of inertia of each leg. This will reduce the power consumption of the three actuators and increase the agility. To meet physical and realistic requirements, the optimization problem is also constrained with bounds on the parameters, with the reachability of a given workspace and with a given range on a kinematic sensitivity index. Since different initial guesses of the optimization process lead to similar objective results, it is proposed to search for several local solutions (morphologies). A methodology is therefore developed to explore the design space and group the results after refinement. The final choice among the obtained solutions is made using additional design criteria based on the sensitivity in terms of dynamic balancing and power consumption with respect to the design parameters.

scholarly journals Social spider optimization algorithm for tuning parameters in PD-like Interval Type-2 Fuzzy Logic Controller applied to a parallel robot

2021 ◽  
Vol 54 (3-4) ◽  
pp. 303-323
Author(s):  
Amjad J Humaidi ◽  
Huda T Najem ◽  
Ayad Q Al-Dujaili ◽  
Daniel A Pereira ◽  
Ibraheem Kasim Ibraheem ◽  
...  
Keyword(s):  
Fuzzy Logic ◽  
Trajectory Tracking ◽  
Fuzzy Logic Controller ◽  
Optimization Technique ◽  
Parallel Robot ◽  
Design Parameters ◽  
Social Spider ◽  
Social Spider Optimization ◽  
Interval Type

This paper presents control design based on an Interval Type-2 Fuzzy Logic (IT2FL) for the trajectory tracking of 3-RRR (3-Revolute-Revolute-Revolute) planar parallel robot. The design of Type-1 Fuzzy Logic Controller (T1FLC) is also considered for the purpose of comparison with the IT2FLC in terms of robustness and trajectory tracking characteristics. The scaling factors in the output and input of T1FL and IT2FL controllers play a vital role in improving the performance of the closed-loop system. However, using trial-and-error procedure for tuning these design parameters is exhaustive and hence an optimization technique is applied to achieve their optimal values and to reach an improved performance. In this study, Social Spider Optimization (SSO) algorithm is proposed as a useful tool to tune the parameters of proportional-derivative (PD) versions of both IT2FLC and T1FLC. Two scenarios, based on two square desired trajectories (with and without disturbance), have been tested to evaluate the tracking performance and robustness characteristics of proposed controllers. The effectiveness of controllers have been verified via numerical simulations based on MATLAB/SIMULINK programming software, which showed the superior of IT2FLC in terms of robustness and tracking errors.

Dynamic trajectory planning for unmanned ship under multi-object environment

2021 ◽  
Author(s):  
Mengxia Li ◽  
Junmin Mou ◽  
Yixiong He ◽  
Xiaohan Zhang ◽  
Qinqiong Xie ◽  
...  
Keyword(s):  
Trajectory Planning ◽  
Unmanned Ship ◽  
Dynamic Trajectory
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