Three-Position Synthesis of Origami-Evolved, Spherically Constrained Spatial Revolute–Revolute Chains

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Kassim Abdul-Sater ◽  
Manuel M. Winkler ◽  
Franz Irlinger ◽  
Tim C. Lueth
Keyword(s):  
Building Blocks ◽  
Design Parameters ◽  
Specific Task ◽  
Spherical Design ◽  
Single Degree Of Freedom ◽  
End Effector ◽  
Single Degree ◽  
Folding Pattern ◽  
Position Synthesis ◽  
Space Requirements

This paper presents a finite position synthesis (f.p.s.) procedure of a spatial single-degree-of-freedom linkage that we call origami-evolved, spherically constrained spatial revolute–revolute (RR) chain here. This terminology is chosen because the linkage may be found from the mechanism equivalent of an origami folding pattern, namely, known as the Miura-ori folding. As shown in an earlier work, the linkage under consideration has naturally given slim shape and essentially represents two specifically coupled spherical four-bar linkages, whose links may be identified with spherical and spatial RR chains. This provides a way to apply the well-developed f.p.s. theory of these linkage building blocks in order to design the origami-evolved linkage for a specific task. The result is a spherically constrained spatial RR chain, whose end effector may reach three finitely separated task positions. Due to an underspecified spherical design problem, the procedure provides several free design parameters. These can be varied in order to match further given requirements of the task. This is shown in a design example with particularly challenging space requirements, which can be fulfilled due to the naturally given slim shape.

scholarly journals Design and integration of a drone based passive manipulator for capturing flying targets

Robotica ◽  
2021 ◽  
pp. 1-16
Author(s):  
B. V. Vidyadhara ◽  
Lima Agnel Tony ◽  
Mohitvishnu S. Gadde ◽  
Shuvrangshu Jana ◽  
V. P. Varun ◽  
...  
Keyword(s):  
The Body ◽  
Outdoor Environment ◽  
Moving Target ◽  
Minimal Energy ◽  
Energy Usage ◽  
Single Degree Of Freedom ◽  
End Effector ◽  
Single Degree ◽  
Measurement Uncertainties ◽  
Manipulator Design

SUMMARY In this paper, we present a novel passive single degree-of-freedom (DoF) manipulator design and its integration on an autonomous drone to capture a moving target. The end-effector is designed to be passive, to disengage the moving target from a flying UAV and capture it efficiently in the presence of disturbances, with minimal energy usage. It is also designed to handle target sway and the effect of downwash. The passive manipulator is integrated with the drone through a single DoF arm, and experiments are carried out in an outdoor environment. The rack-and-pinion mechanism incorporated for this manipulator ensures safety by extending the manipulator beyond the body of the drone to capture the target. The autonomous capturing experiments are conducted using a red ball hanging from a stationary drone and subsequently from a moving drone. The experiments show that the manipulator captures the target with a success rate of 70% even under environmental/measurement uncertainties and errors.

scholarly journals Miura-ori, Basics for Designing its Folding Machines

2019 ◽  
Vol 2 ◽  
pp. 1-5
Author(s):  
Koryo Miura
Keyword(s):  
Basic Concept ◽  
High Speed ◽  
Geometric Property ◽  
Unique Property ◽  
Degree Of Freedom ◽  
Design Parameters ◽  
Geometric Properties ◽  
Single Degree Of Freedom ◽  
Single Degree

<p><strong>Abstract.</strong> The unique property of the Miura-ori map is due to the geometric property of “the single degree of freedom”. With this, one can open a map with a single pull motion. However, due to this property, the high-speed folding machine is difficult to realized. In this presentation, author investigates the natural geometric properties of Miura-ori in detail and proposes a basic concept for designing its folding machine. Though, the result does not provide a draft of a folding machine, the basics for the design parameters is beneficial for future works.</p>

scholarly journals Using the Singularity Trace to Understand Linkage Motion Characteristics

2013 ◽  
Author(s):  
Lin Li ◽  
David H. Myszka ◽  
Andrew P. Murray ◽  
Charles W. Wampler
Keyword(s):  
Critical Points ◽  
Design Parameter ◽  
Closed Loop ◽  
Design Parameters ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Net Zero ◽  
Motion Characteristics ◽  
Number Of Branches ◽  
Activation Sequence

This paper provides examples of a method used to analyze the motion characteristics of single-degree-of-freedom, closed-loop linkages under study a designated input angle and one or two design parameters. The method involves the construction of a singularity trace, which is a plot that reveals changes in the number of geometric inversions, singularities, and changes in the number of branches as a design parameter is varied. This paper applies the method to Watt II, Stephenson III and double butterfly linkages. For the latter two linkages, instances where the input angle is able to rotate more than one revolution between singularities have been identified. This characteristic demonstrates a net-zero, singularity free, activation sequence that places the mechanism into a different geometric inversion. Additional observations from the examples are given. Instances are shown where the singularity trace for the Watt II linkage includes multiple coincident projections of the singularity curve. Cases are shown where subtle changes to two design parameters of a Stephenson III linkage drastically alters the motion. Additionally, isolated critical points are found to exist for the double butterfly, where the linkage becomes a structure and looses the freedom to move.

A Finite-Element-Based Method to Determine the Spatial Stiffness Properties of a Notch Hinge

1998 ◽  
Vol 123 (1) ◽  
pp. 141-147 ◽  
Author(s):  
Shilong Zhang ◽  
Ernest D. Fasse
Keyword(s):  
Finite Element ◽  
Finite Element Methods ◽  
Joint Stiffness ◽  
Degree Of Freedom ◽  
Design Parameters ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Stiffness Properties ◽  
Six Degree Of Freedom ◽  
Flexural Hinges

Notch hinges are flexural hinges used to make complex, precise mechanisms. They are typically modeled as single degree-of-freedom hinges with an associated joint stiffness. This is not adequate for all purposes. This paper computes the six degree-of-freedom stiffness properties of notch hinges using finite element methods. The results are parameterized in terms of meaningful design parameters.

scholarly journals Design of a Compact, Reconfigurable, Prosthetic Wrist

2012 ◽  
Vol 9 (1) ◽  
pp. 117-124 ◽  
Author(s):  
Arthur Zinck ◽  
Øyvind Stavdahl ◽  
Edmund Biden ◽  
Peter J. Kyberd
Keyword(s):  
Functional Performance ◽  
Degree Of Freedom ◽  
Spherical Design ◽  
Single Degree Of Freedom ◽  
Oblique Orientation ◽  
Single Degree ◽  
Axis Of Rotation

The design of a prosthetic wrist is the result of compromises between the function and the practicality of the device. Conventional prosthetic wrists use a single degree of freedom to produce pro/supination of the hand. It has not been demonstrated that this is the most functional alignment for a single axis. Previous work by the authors suggests that if the wrist must have only one rotatory axis then a more oblique orientation would be more functional. To test this idea, a compact wrist with a single axis and spherical design has been made that will allow any axis of rotation to be selected and the functional performance of the resulting arm be tested.

Design of a Cam-Actuated Robotic Leg

2014 ◽  
Author(s):  
Diane L. Peters ◽  
Steven Chen
Keyword(s):  
Optimization Problem ◽  
Angular Displacement ◽  
Design Parameters ◽  
Single Degree Of Freedom ◽  
Advantages And Disadvantages ◽  
Single Degree ◽  
Error Metric ◽  
Robotic Leg ◽  
Foot Position ◽  
Leg Design

This paper presents a concept for a single-degree-of-freedom robotic leg, where the lower and upper leg are each controlled by a cam. The two cams are mounted on a common shaft, and are rotating at the same speed. The relevant equations for the mechanism’s kinematics are first developed, to express the position of the foot in terms of the cam’s angular displacement and various design parameters such as link lengths. Next, the design problem is formulated as an optimization, where the objective is to minimize an error metric that compares the foot position to the desired trajectory of the foot. The constraints in the optimization problem include important parameters such as the pressure angle of the cams, as well as a set of constraints to ensure that the leg will fit on an appropriately sized legged robot. Finally, the results are discussed, with a focus on what the advantages and disadvantages of this leg design might be as compared to other types of robotic leg designs.

Four-Position Synthesis for Spatial Mechanisms With Two Independent Loops

1992 ◽  
Author(s):  
Chien H. Chiang ◽  
Wei Hua Chieng ◽  
David A. Hoeltzel
Keyword(s):  
Rigid Body ◽  
Mathematical Models ◽  
Analytical Methods ◽  
Degree Of Freedom ◽  
Single Degree Of Freedom ◽  
Practical Applications ◽  
Single Degree ◽  
Spatial Mechanisms ◽  
Position Synthesis ◽  
Independent Loops

Abstract Mathematical models that have been employed to synthesize spatial mechanisms for rigid body guidance have been found to be too complicated to implement in practical applications, especially for four-position guidance synthesis. This paper describes simple analytical methods for synthesizing single degree-of-freedom spatial mechanisms having two independent loops for four precision positions. In addition, prescribed timing has been simultaneously considered for several spatial mechanisms.

Computer Analysis of the Dynamic Contact Behavior and Tracking Characteristics of a Single-Degree-of-Freedom Slider Model for a Contact Recording Head

1995 ◽  
Vol 117 (1) ◽  
pp. 124-129 ◽  
Author(s):  
Kyosuke Ono ◽  
Hiroshi Yamamura ◽  
Takaaki Mizokoshi
Keyword(s):  
Contact Stiffness ◽  
Time History ◽  
Dynamic Contact ◽  
Disk Surface ◽  
Degree Of Freedom ◽  
Design Parameters ◽  
Single Degree Of Freedom ◽  
Contact Behavior ◽  
Single Degree ◽  
Contact Slider

This paper presents a new theoretical approach to the dynamic contact behavior and tracking characteristics of a contact slider that is one of the candidates of head design for future high density magnetic recording disk storages. A slider and its suspension are modeled as a single-degree-of-freedom vibration system. The disk surface is assumed to have a harmonic wavy roughness with linear contact stiffness and damping. From the computer simulation of the time history of the slider motion after dropping from the initial height of 10 nm, it is found that the contact vibration of the slider can attenuate and finally track on the wavy disk surface in a low waviness frequency range. As the waviness frequency increases, however, the slider cannot stay on the disk surface and comes to exhibit a variety of contact vibrations, such as sub- and super-harmonic resonance responses and finally comes to exhibit non-periodic vibration. It is also found that, among design parameters, the slider load to mass ratio and contact damping can greatly increase the surface waviness frequency and amplitude for which the stable tracking of a contact slider is possible.

Kinematic and Kinetostatic Synthesis of Planar Coupled Serial Chain Mechanisms

2002 ◽  
Vol 124 (2) ◽  
pp. 301-312 ◽  
Author(s):  
Venkat Krovi ◽  
G. K. Ananthasuresh ◽  
Vijay Kumar
Keyword(s):  
Degree Of Freedom ◽  
Dimensional Synthesis ◽  
Single Degree Of Freedom ◽  
End Effector ◽  
Solution Approach ◽  
Single Degree ◽  
Design Specifications ◽  
Serial Chain ◽  
Gear Trains ◽  
External Loads

Single Degree-of-freedom Coupled Serial Chain (SDCSC) mechanisms form a novel class of modular and compact mechanisms with a single degree-of-freedom, suitable for a number of manipulation tasks. Such SDCSC mechanisms take advantage of the hardware constraints between the articulations of a serial-chain linkage, created using gear-trains or belt/pulley drives, to guide the end-effector motions and forces. In this paper, we examine the dimensional synthesis of such SDCSC mechanisms to perform desired planar manipulation tasks, taking into account task specifications on both end-effector motions and forces. Our solution approach combines precision point synthesis with optimization to realize optimal mechanisms, which satisfy the design specifications exactly at the selected precision points and approximate them in the least-squares sense elsewhere along a specified trajectory. The designed mechanisms can guide a rigid body through several positions while supporting arbitrarily specified external loads. Furthermore, torsional springs are added at the joints to reduce the overall actuation requirements and to enhance the task performance. Examples from the kinematic and the kinetostatic synthesis of planar SDCSC mechanisms are presented to highlight the benefits.

scholarly journals Pre-Acting Control for Shock and Impact Isolation Systems

2005 ◽  
Vol 12 (1) ◽  
pp. 49-65 ◽  
Author(s):  
D.V. Balandin ◽  
N.N. Bolotnik ◽  
W.D. Pilkey
Keyword(s):  
Performance Index ◽  
Design Parameters ◽  
Control Force ◽  
Isolation System ◽  
Single Degree Of Freedom ◽  
Absolute Value ◽  
Single Degree ◽  
Shock Impact ◽  
Isolation Systems ◽  
Isolation Performance

Pre-acting control in shock/impact isolation systems is studied. With pre-acting control, the isolation system begins to respond to an impact before this impact has been applied to the base. The limiting performance of the isolator with pre-acting control is investigated for a single-degree-of-freedom system subject to an instantaneous impact. The isolation performance index is defined as the maximum of the absolute value of the displacement of the object to be isolated relative to the base, provided that the magnitude of the control force transmitted to the object does not exceed a prescribed value. It is shown that there is a substantial advantage in the use of pre-acting isolators over isolators without pre-action. Particular attention is given to a pre-acting isolator based on a passive elastic element (a spring) separating the object to be protected from the base. An example illustrates the calculation of the design parameters of such an isolator.

Sign in / Sign up

Export Citation Format

Share Document