Kinematics and Force Optimization for Efficient Self-Reconfiguration of Chain-Type Modular Robots

2005 ◽  
Author(s):  
Carl A. Nelson ◽  
Raymond J. Cipra
Keyword(s):  
Mechanical Energy ◽  
Primary Objective ◽  
Modular Robots ◽  
Kinematic Modeling ◽  
Unified Framework ◽  
Kinematic Constraint ◽  
Modeling And Analysis ◽  
Force Optimization ◽  
Reconfiguration Planning ◽  
Chain Type

The problem of self-reconfiguration planning for chain-type unit-modular robots is a complex one, with many issues yet to be successfully addressed. This paper describes an approach to several sub-problems associated with self-reconfiguration, namely kinematic modeling and analysis, including kinematic constraint satisfaction, and load analysis and redistribution. These issues are addressed in a unified framework whose primary objective is minimization of the time and mechanical energy expended during reconfiguration. Computer simulation efforts are described and results presented.

On Optimal Planning for DNA Nanomechanical Robots

2014 ◽  
Vol 983 ◽  
pp. 67-70
Author(s):  
Vladimir Popov
Keyword(s):  
Neural Networks ◽  
Modular Robots ◽  
Planning Problem ◽  
Optimal Planning ◽  
Intelligent Algorithm ◽  
Virtual Force ◽  
Optimal Reconfiguration ◽  
Genetic Sequences ◽  
Reconfiguration Planning ◽  
Chain Type

In this paper, we consider the optimal reconfiguration planning problem of finding the least number of reconfiguration steps to transform between two configurations for chain-type modular robots. We propose an intelligent algorithm for solution of the problem. In particular, we use the set of parameterized k-covers problem and the approximate period problem to detect periodic regularities in genetic sequences of DNA nanomechanical robots. We try to use similar reconfiguration actions for similar parts of genetic sequences. We consider an artificial physics optimization algorithm. We use Runge Kutta neural networks for the prediction of virtual force law.

Iterative Fixture Layout and Clamping Force Optimization Using the Genetic Algorithm

2001 ◽  
Vol 124 (1) ◽  
pp. 119-125 ◽  
Author(s):  
Krishnakumar Kulankara ◽  
Srinath Satyanarayana ◽  
Shreyes N. Melkote
Keyword(s):  
Genetic Algorithm ◽  
Nonlinear Programming ◽  
Primary Objective ◽  
Fixture Design ◽  
Clamping Force ◽  
Optimal Solutions ◽  
Fixture Layout ◽  
Force Optimization ◽  
Nonlinear Programming Methods ◽  
Objective Being

Fixture design is a critical step in machining. An important aspect of fixture design is the optimization of the fixture, the primary objective being the minimization of workpiece deflection by suitably varying the layout of fixture elements and the clamping forces. Previous methods for fixture design optimization have treated fixture layout and clamping force optimization independently and/or used nonlinear programming methods that yield sub-optimal solutions. This paper deals with application of the genetic algorithm (GA) for fixture layout and clamping force optimization for a compliant workpiece. An iterative algorithm that minimizes the workpiece elastic deformation for the entire cutting process by alternatively varying the fixture layout and clamping force is proposed. It is shown via an example of milling fixture design that this algorithm yields a design that is superior to the result obtained from either fixture layout or clamping force optimization alone.

Kinematic analysis of deployable parallel mechanisms

2019 ◽  
Vol 234 (1) ◽  
pp. 263-272 ◽  
Author(s):  
Shuofei Yang ◽  
Yangmin Li
Keyword(s):  
Kinematic Analysis ◽  
Theoretical Foundation ◽  
Parallel Mechanisms ◽  
Solar Panels ◽  
Kinematic Modeling ◽  
Modeling And Analysis ◽  
Velocity Modeling ◽  
Parallel Structures ◽  
Simulation And Experiment ◽  
Instantaneous Screw

Inspired by the existing closed-loop deployable mechanisms and parallel mechanisms, a new kind of mechanisms, named deployable parallel mechanisms, is introduced in this paper, and the kinematic analysis is presented. As the combination of deployable mechanisms and parallel mechanisms, deployable parallel mechanisms have advantages of both the two kinds of mechanisms. They can be easily constructed by origami and folded from spatial structures into paper slices. Due to the parallel structures, they can be designed to have higher stiffness and larger volume compressibility than the existing deployable mechanisms. Thus, deployable parallel mechanisms have tremendous potential to be applied in the design of spatial solar panels, elastic reconfigurable robotic modules, etc. With reference to the kinematic analysis of parallel mechanisms, a finite and instantaneous screw method for kinematics of deployable parallel mechanisms is proposed, which is a generic method that is suitable for displacement and velocity modeling and analysis of any deployable parallel mechanism. A typical mechanism with symmetrical structure is taken as an example to show the validity of the proposed method, and simulation and experiment are carried out to verify the obtained results of kinematics. This paper puts forth the basic concepts of deployable parallel mechanisms and lays a theoretical foundation for their kinematic modeling and analysis.

Comprehensive Hydromechanical Specific Energy Calculation for Drilling Efficiency

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Kshitij Mohan ◽  
Faraaz Adil ◽  
Robello Samuel
Keyword(s):  
Specific Energy ◽  
Drilling Fluid ◽  
Mechanical Energy ◽  
Energy Calculation ◽  
Energy Term ◽  
Modeling And Analysis ◽  
Mechanical Specific Energy ◽  
Available Energy ◽  
Jet Impact ◽  
Drilling Conditions

Over the last few years, different types of bits have been introduced to meet the challenges of steerable as well as rotary steerable systems; and it is imperative that bits be utilized optimally in these systems. As challenges increase with increasing depths, it becomes even more important for one to efficiently utilize the available energy (Robello, S., 2013, “Modeling and Analysis of Drillstring Vibration in Riserless Environment,” ASME J. Energy Res. Technol., 135(1), p. 013101). A new correlation identifying inefficient drilling conditions is presented in this paper. Mechanical specific energy (MSE) has been used to improve drilling rates, with mixed results. Hydro MSE (HMSE), which is introduced here, encompasses hydraulic as well as mechanical energy. HMSE quantifies the amount of energy required to drill a unit volume of rock and remove it from underneath the bit. HMSE includes axial, torsional, and hydraulic energy and is different from MSE because it includes a hydraulic term. The initial MSE correlation (Teale, R., 1965, “The Concept of Specific Energy in Rock Drilling,” Int. J. Rock Mech. Min. Sci., 2, pp. 57–73.) was modified to accommodate the new hydraulic term. This paper attempts to better model downhole drilling by introducing the hydraulic energy term in the MSE correlation by defining it as HMSE. While the majority of the drilling occurs because of the bit, it is a well-known fact that some drilling occurs due to the “jet impact impingement” caused by the drilling fluid as well. Experimental and field data presented in this paper show that HMSE can identify inefficient drilling conditions. The new hydraulic term included in the specific energy correlation is the key to correctly match the amount of energy required to drill and overcome the strength and stresses of formation being drilled. Also, this new term illustrates how much hydraulic energy is needed to drill faster when the mechanical energy (axial and torsional) is increased. The results also show the importance of including the bit hydraulic energy term into any specific energy analysis for drilling optimization. Field results reveal specific patterns for inefficient drilling conditions and also reveal a good correlation between calculated HMSE and the expected requirements for rock removal under existent conditions of stress at the bit face (Mohan, K., and Robello Samuel, F. A., 2009, “Tracking Drilling Efficiency Using Hydro-Mechanical Specific Energy,” SPE/IADC Drilling Conference and Exhibition, March 17–19, Amsterdam, The Netherlands, No. SPE 119421).

scholarly journals Development, Kinematic Modeling and Analysis of 3 (DoF) Pneumatic Gantry Robot

2020 ◽  
Vol 5 (6) ◽  
pp. 646-650
Author(s):  
Awad Eisa G. Mohamed ◽  
Abuobeida Mohammed Elhassan
Keyword(s):  
Controller Design ◽  
Low Cost ◽  
Weight Ratio ◽  
Friction Model ◽  
Pneumatic Cylinder ◽  
Kinematic Modeling ◽  
Low Friction ◽  
Modeling And Analysis ◽  
Gantry Robot ◽  
Pneumatic Cylinders

Low friction pneumatic cylinders are now being considered in applications for which only electric motors or hydraulics were previously considered suitable. One potential application of low friction pneumatics is robotic for metallurgical operations where the high power to weight ratio and low cost could be exploited. As part of an ongoing project to develop a pneumatic robot, this paper presents the kinematic analysis of pneumatic cylinder characteristics that simplifies controller design. Using mathematical modeling and simulation, non-linearity of modern pneumatic systems have been investigated. The derived models give an excellent representation of the system, despite the inclusion of a simplified friction model.

Kinematic Modeling and Analysis of a Novel Bio-Inspired and Cable-Driven Hybrid Shoulder Mechanism

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
A. S. Niyetkaliyev ◽  
E. Sariyildiz ◽  
G. Alici
Keyword(s):  
Degrees Of Freedom ◽  
Kinematic Model ◽  
Three Dimensional ◽  
Parallel Manipulators ◽  
Kinematic Modeling ◽  
Interaction Forces ◽  
Modeling And Analysis ◽  
Shoulder Joints ◽  
Hybrid Mechanism ◽  
Simulation Results

Abstract The robotic shoulder rehabilitation exoskeletons that do not take into consideration all shoulder degrees-of-freedom (DOFs) lead to undesirable interaction forces and cause discomfort to the patient due to the joint axes misalignments between the exoskeleton and shoulder joints. In order to contribute to the solution of this human–robot compatibility issue, we present the kinematic modeling and analysis of a novel bio-inspired 5-DOFs hybrid human–robot mechanism (HRM). The human limbs are regarded as the inner passive restrained links in the proposed hybrid constrained anthropomorphic mechanism. The proposed hybrid mechanism combines serial and parallel manipulators with rigid and cable links enabling a match between human and exoskeleton joint axes. It is designed to cover the whole range of motion of the human shoulder with the workspace free of singularities. The numerical and simulation results from the computer-aided drawing model of the mechanism are presented to demonstrate the validity of the kinematic model, and the kinematic and singularity merits of the proposed mechanism. A three-dimensional printed prototype of the hybrid mechanism was fabricated to further validate the kinematic model and its overall advantages.

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