Optimal, Model-Based Design of Soft Robotic Manipulators

2008 ◽  
Vol 130 (9) ◽  
Author(s):  
Deepak Trivedi ◽  
Dustin Dienno ◽  
Christopher D. Rahn
Keyword(s):  
Nonlinear Models ◽  
Load Capacity ◽  
Robotic Manipulators ◽  
Cluttered Environments ◽  
Rod Theory ◽  
Cosserat Rod ◽  
Manipulator Design ◽  
Air Muscle ◽  
Muscle Actuators ◽  
General Method

Soft robotic manipulators, unlike their rigid-linked counterparts, deform continuously along their lengths similar to elephant trunks and octopus arms. Their excellent dexterity enables them to navigate through unstructured and cluttered environments and to handle fragile objects using whole arm manipulation. This paper develops optimal designs for OctArm manipulators, i.e., multisection, trunklike soft arms. OctArm manipulator design involves the specification of air muscle actuators and the number, length, and configuration of sections that maximize dexterity and load capacity for a given maximum actuation pressure. A general method of optimal design for OctArm manipulators using nonlinear models of the actuators and arm mechanics is developed. The manipulator model is based on Cosserat rod theory, accounts for large curvatures, extensions, and shear strains, and is coupled to the nonlinear Mooney–Rivlin actuator model. Given a dexterity constraint for each section, a genetic algorithm-based optimizer maximizes the arm load capacity by varying the actuator and section dimensions. The method generates design rules that simplify the optimization process. These rules are then applied to the design of pneumatically and hydraulically actuated OctArm manipulators using 100psi and 1000psi maximum pressures, respectively.

Optimal, Model-Based Design of Soft Robotic Manipulators

2007 ◽  
Author(s):  
Deepak Trivedi ◽  
Dustin Dienno ◽  
Christopher D. Rahn
Keyword(s):  
Nonlinear Models ◽  
Load Capacity ◽  
Robotic Manipulators ◽  
Maximum Pressure ◽  
Cluttered Environments ◽  
Rod Theory ◽  
Cosserat Rod ◽  
Manipulator Design ◽  
Air Muscle ◽  
Muscle Actuators

Soft robotic manipulators, unlike their rigid-linked counterparts, deform continuously along their lengths similar to elephant trunks and octopus arms. Their excellent dexterity enables them to navigate through unstructured and cluttered environments and handle fragile objects using whole arm manipulation. Soft robotic manipulator design involves the specification of air muscle actuators and the number, length and configuration of sections that maximize dexterity and load capacity for a given maximum actuation pressure. This paper uses nonlinear models of the actuators and arm structure to optimally design soft robotic manipulators. The manipulator model is based on Cosserat rod theory, accounts for large curvatures, extensions, and shear strains, and is coupled to nonlinear Mooney-Rivlin actuator model. Given a dexterity constraint for each section, a genetic algorithm-based optimizer maximizes the arm load capacity by varying the actuator and section dimensions. The method generates design rules that simplify the optimization process. These rules are then applied to the design of pneumatically and hydraulically actuated soft robotic manipulators, using 100 psi and 1000 psi maximum pressure, respectively.

Optimization in the Design and Control of Robotic Manipulators: A Survey

1989 ◽  
Vol 42 (4) ◽  
pp. 117-128 ◽  
Author(s):  
S. S. Rao ◽  
P. K. Bhatti
Keyword(s):  
Optimal Control ◽  
Robot Manipulator ◽  
Research Effort ◽  
Industrial Robot ◽  
Load Capacity ◽  
Robotic Manipulators ◽  
Optimization Techniques ◽  
Highly Nonlinear ◽  
Manipulator Design ◽  
And Control

Robotics is a relatively new and evolving technology being applied to manufacturing automation and is fast replacing the special-purpose machines or hard automation as it is often called. Demands for higher productivity, better and uniform quality products, and better working environments are primary reasons for its development. An industrial robot is a multifunctional and computer-controlled mechanical manipulator exhibiting a complex and highly nonlinear behavior. Even though most current robots have anthropomorphic configurations, they have far inferior manipulating abilities compared to humans. A great deal of research effort is presently being directed toward improving their overall performance by using optimal mechanical structures and control strategies. The optimal design of robot manipulators can include kinematic performance characteristics such as workspace, accuracy, repeatability, and redundancy. The static load capacity as well as dynamic criteria such as generalized inertia ellipsoid, dynamic manipulability, and vibratory response have also been considered in the design stages. The optimal control problems typically involve trajectory planning, time-optimal control, energy-optimal control, and mixed-optimal control. The constraints in a robot manipulator design problem usually involve link stresses, actuator torques, elastic deformation of links, and collision avoidance. This paper presents a review of the literature on the issues of optimum design and control of robotic manipulators and also the various optimization techniques currently available for application to robotics.

scholarly journals A discrete mechanics approach to the Cosserat rod theory-Part 1: static equilibria

2010 ◽  
Vol 85 (1) ◽  
pp. 31-60 ◽  
Author(s):  
Pascal Jung ◽  
Sigrid Leyendecker ◽  
Joachim Linn ◽  
Michael Ortiz
Keyword(s):  
Discrete Mechanics ◽  
Rod Theory ◽  
Cosserat Rod

scholarly journals Integration of Nonlinear Models of Flexible Body Deformation in Multibody System Dynamics

2013 ◽  
Vol 9 (1) ◽  
Author(s):  
Martin Schulze ◽  
Stefan Dietz ◽  
Bernhard Burgermeister ◽  
Andrey Tuganov ◽  
Holger Lang ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Multibody System ◽  
Nonlinear Models ◽  
Equations Of Motion ◽  
Flexible Structures ◽  
General Purpose ◽  
Cosserat Rod ◽  
Rod Model ◽  
Flexible Deformation ◽  
Run Up

Current challenges in industrial multibody system simulation are often beyond the classical range of application of existing industrial simulation tools. The present paper describes an extension of a recursive order-n multibody system (MBS) formulation to nonlinear models of flexible deformation that are of particular interest in the dynamical simulation of wind turbines. The floating frame of reference representation of flexible bodies is generalized to nonlinear structural models by a straightforward transformation of the equations of motion (EoM). The approach is discussed in detail for the integration of a recently developed discrete Cosserat rod model representing beamlike flexible structures into a general purpose MBS software package. For an efficient static and dynamic simulation, the solvers of the MBS software are adapted to the resulting class of MBS models that are characterized by a large number of degrees of freedom, stiffness, and high frequency components. As a practical example, the run-up of a simplified three-bladed wind turbine is studied where the dynamic deformations of the three blades are calculated by the Cosserat rod model.

Design of a Soft Multi-Degree of Freedom Tool Positioner With Variable Stiffness Integrating Molded Air Muscles Actuation, Granular Jamming and Dielectric Elastomer Sensing

2015 ◽  
Author(s):  
Guillaume Bouliane-Blais ◽  
Jean-Sébastien Plante
Keyword(s):  
Variable Stiffness ◽  
Dielectric Elastomer ◽  
Degree Of Freedom ◽  
Soft Robotics ◽  
Initial Stiffness ◽  
Trade Off ◽  
Position Feedback ◽  
Constrained Environments ◽  
Air Muscle ◽  
Muscle Actuators

Soft technology is more and more present in robotics allowing safe interaction with humans, high dexterity in constrained environments, and safe manipulation of fragile or undefined objects. However, soft robotics is limited by a fundamental trade-off between available workspace and stiffness. Position feedback is also challenging as soft robots generally use deformable mechanisms instead of discrete joints. Here, the design of a soft four-degree-of-freedom tool positioner integrating a brake system and a soft sensor is proposed to address these issues. The design integrates molded air muscle actuators, granular jamming brakes, and Dielectric Elastomer Sensors (DES). The design is experimentally validated based on the requirements of a manipulator for liver cancer treatment, which is a representative application of soft robotics. The use of granular jamming mitigates the fundamental trade-off of soft robotics as it allows the manipulator to reach a large workspace (1500 cm3) while having the capacity to provide a high stiffness (up to19 times the initial stiffness). DES provides satisfactory position feedback, demonstrating a 0.69 mm accuracy that is lower than the 1 mm requirement. The proposed design using granular jamming and DES could greatly benefit human-safe and medical robotics.

KINKS AND BOUNCES FROM ZERO MODES

1991 ◽  
Vol 06 (30) ◽  
pp. 5467-5479 ◽  
Author(s):  
JAVIER CASAHORRAN ◽  
SOONKEON NAM
Keyword(s):  
Natural Number ◽  
Morse Potential ◽  
Nonlinear Models ◽  
Liouville Theory ◽  
Field Theories ◽  
Classical Solutions ◽  
Zero Modes ◽  
New Family ◽  
General Method

We describe a general method of obtaining nonlinear models possessing either topological or nontopological classical solutions. In particular, the program can be carried out when the so-called stability equations are derived from group-theoretical arguments. Using Schrödinger-like equations with Pöschl-Teller potential, which is related to SU(2), we obtain interesting field theories labeled by a natural number l. We also consider Rosen-Morse potential, which is related to SL (2, C), getting a new family of models. Previously known examples, such as sine-Gordon, Φ4 and Liouville theory, are obtained in this context.

Magnetically-doped polydimethylsiloxane for artificial muscle applications

2019 ◽  
Vol 13 (01) ◽  
pp. 1950089
Author(s):  
Erik Ventura ◽  
Cagri Oztan ◽  
Diego Palacios ◽  
Irene Isabel Vargas ◽  
Emrah Celik
Keyword(s):  
Additive Manufacturing ◽  
Mechanical Response ◽  
Load Capacity ◽  
Artificial Muscle ◽  
Artificial Muscles ◽  
Test Results ◽  
Method Of Production ◽  
Muscle Actuators ◽  
Doped Polymer

Artificial muscle actuators demonstrate great potential for improving the quality of life. Recently, polymer muscle actuators have attracted attention due to their inexpensive and highly versatile methods of fabrication along with decent mechanical properties that can mimic those of natural muscles. The aim of this research is to investigate the usability of a magnetite-doped polymer powder, polydimethylsiloxane (PDMS), for artificial muscle actuators through an inexpensive method of production. PDMS samples doped with different levels of magnetite were fabricated using molds that were produced by additive manufacturing. Subsequently, the samples were magnetically and mechanically characterized by investigation of strength, elastic modulus, failure strain and permittivity, which are vital to meet the load capacity. The test results demonstrated that the mechanical and magnetic properties could be tailored as a function of doping level. Matching the mechanical response of these artificial components to those of artificial muscles will reduce the residual stresses, enhance the artificial muscle life and allow wider use of these materials for biomedical applications. This research rendered fabrication of molds possible for various applications where geometric customization of the actuator is required to meet endure severe loads, thanks to the freeform nature of additive manufacturing.

scholarly journals Kinematic Analysis and Evaluation of Wheelchair Mounted Robotic Arms

2004 ◽  
Author(s):  
Edward J. McCaffrey ◽  
Redwan M. Alqasemi ◽  
Rajiv V. Dubey
Keyword(s):  
Kinematic Analysis ◽  
Daily Living ◽  
Analytical Procedure ◽  
Robotic Manipulators ◽  
Rehabilitation Robotics ◽  
Robotic Arms ◽  
Design Recommendations ◽  
Analysis And Evaluation ◽  
The Past ◽  
Manipulator Design

There has been significant progress in bringing commercially-viable wheelchair mounted robotic arms (WMRA) into the marketplace in the past 30 years. This paper focuses on kinematic analysis and evaluation of such robotic arms. It addresses the kinematics of the WMRA with respect to its ability to reach common positions while performing activities of daily living (ADL). A procedure is developed for the kinematic analysis and evaluation of a wheelchair mounted robotic arm. In addition to developing the analytical procedure, the manipulator is evaluated, and design recommendations and insights are obtained. Current commercially-available wheelchair mountable robotic manipulators have been designed specifically for use in rehabilitation robotics. In an effort to evaluate two commercial manipulators, the procedure for kinematic analysis is applied to each manipulator. Design recommendations with regard to each device are obtained. This method will benefit the researchers by providing a standardized procedure for kinematic analysis of WMRAs that is capable of evaluating independent designs.

Sign in / Sign up

Export Citation Format

Share Document