Soft Planar Actuator using Pneumatic-Rubber Balls

2000 ◽  
Vol 12 (3) ◽  
pp. 254-260 ◽  
Author(s):  
Toshiro Noritsugu ◽  
◽  
Daijyu Kaneshiro ◽  
Takashi Inoue
Keyword(s):  
Elastic Deformation ◽  
Silicone Rubber ◽  
Control Method ◽  
Fundamental Principle ◽  
Compressed Air ◽  
Rubber Tube ◽  
Carrier System ◽  
Soft Actuator ◽  
System A ◽  
Soft Actuators

The manipulation of fragile and shapeless objects requires an actuator with enough flexibility and safety not to injure manipulated objects. To cope with such requirements, soft actuators have been developed, most of which utilize elastic deformation of a rubber tube or balloon caused by compressed air pressure. Such a pneumatic rubber actuator is expected to be effectively used as a flexible and friendly soft actuator in various fields. In this study, to realize a flexible pneumatic carrier system, a soft planar actuator using rubber balls has been developed assuming that the actuator directly contacts carried objects. This paper describes a fundamental principle of operation, a control method and experimental results. Additionally, a small sized soft planar actuator made of silicone rubber is described. The results show the effectiveness of the proposed actuator mechanism.

Development of Pneumatic Rotary Soft Actuator Made of Silicone Rubber

2001 ◽  
Vol 13 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Toshiro Noritsugu ◽  
◽  
Mitsuhiko Kubota ◽  
Sadaharu Yoshimatsu
Keyword(s):  
Silicone Rubber ◽  
Control Algorithm ◽  
Compressed Air ◽  
Robot Hand ◽  
Soft Robot ◽  
Human Beings ◽  
Partial Difference ◽  
Soft Actuator ◽  
Fundamental Properties ◽  
Rotary Type

A soft actuator with inherent flexibility has been required to built up a soft mechanical drive system such as a human beings collaboration robot and a welfare machine. In this study, a rotary type soft actuator made of silicone rubber driven with compressed air has been developed. This actuator can realize the desired rotary operation by using the fiber reinforcement and the partial difference of stiffness owing to the rubber thickness. In this paper, the structure and operational principle of the actuator is described, and the fundamental properties of actuator are experimentally investigated. The experimental results show that the actuator has the sufficiently large operational angle and the dynamic characteristics of a damping and elasticity component. Its application to a soft robot finger and a robot hand are discussed. Owing to the flexibility of actuator, this hand can grasp unshaped or flexible objects without any complicated control algorithm. The availability of this actuator is confirmed through some experiments.

scholarly journals Operator-Based Nonlinear Control for a Miniature Flexible Actuator Using the Funnel Control Method

Machines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 26
Author(s):  
Keisuke Ueno ◽  
Shuhei Kawamura ◽  
Mingcong Deng
Keyword(s):  
Nonlinear Control ◽  
Tracking Control ◽  
Control Method ◽  
Boundary Function ◽  
Soft Actuator ◽  
Design Scheme ◽  
Adaptive Law ◽  
Control Gain ◽  
Soft Actuators ◽  
Funnel Control

Recently, the studies of soft actuators have been getting increased attention among various fields. Soft actuators are very safe for fragile objects and have an affinity to humans because they are composed of flexible materials. A miniature flexible actuator is a kind of pneumatically driven soft actuator. It has a bellowed shape and asymmetrical structure. This shape can generate a curling motion in two ways under positive and negative pressures with only one air tube. In the previous article, a control system using adaptive λ-tracking control was proposed. This control gain can become too large as time tends to infinity because the adaptive law exhibits a non-decreasing gain. To solve this problem, the funnel control method is proposed. The adaptive gain of this method not only increases but also decreases; however, the design scheme of the boundary function which is needed to decide on adaptive gain is not proposed here. In this article, an operator-based nonlinear control system’s design and the design scheme of the boundary function using an observer are proposed. Then, the effectiveness of the proposed method is verified by a simulation and an experiment.

scholarly journals Research on performance of rigid-hoop-reinforced multi-DOF soft actuator

2021 ◽  
Vol 13 (6) ◽  
pp. 168781402110267
Author(s):  
Jin Sun ◽  
Daozhou Zhang ◽  
Yang Zhang ◽  
Xinglong Zhu ◽  
Juntong Xi ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Silicone Rubber ◽  
Spring Steel ◽  
High Load ◽  
The Body ◽  
Load Carrying Capacity ◽  
Bending Angle ◽  
Soft Actuator ◽  
Load Carrying ◽  
Soft Actuators

In order to improve the bearing capacity of soft actuators, this article presents the development of the rigid-hoop-reinforced (spring or steel hoop) multi-DOF soft actuator. The actuator is composed of a rotary module with spring reinforcement on the silicone rubber-based body and a bending module with steel hoop reinforcement on the body. Compared with fiber-reinforced actuators, the bearing capacities of rigid-hoop-reinforced actuators made of 65Mn spring steel are improved. The radial and the axial bearing capacity for the bending module and the rotary module is raised by 29.6%, 28.2%, 30.6%, 49.6% respectively; under the same pressure, the spring-reinforced interval increases the maximum rotary angle of the rotary module, the steel hoop-reinforced interval increases the maximum bending angle of the bending module; with the same reinforcement type, the bending module with reinforcement interval of 10 mm has good bending characteristics that the bending angle changes with the pressure gently; the lower the hardness of silicone rubber base body, the better the adaptability and flexibility of the actuator, and the higher the hardness, the greater the bearing capacity of the actuator. Due to the above advantages, the rigid-hoop-reinforced multi-DOF soft actuator can be applied to medical devices which need high load-carrying capacity.

DESIGN AND ANALYSIS OF BENDING MOTION IN SINGLE AND DUAL CHAMBER BELLOWS STRUCTURED SOFT ACTUATORS

2016 ◽  
Vol 78 (6-13) ◽  
Author(s):  
Tariq Rehman ◽  
A. A. M. Faudzi ◽  
Dyah Ekashanti Octorina Dewi ◽  
K. Suzumori ◽  
M. R. M. Razif ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Silicone Rubber ◽  
Soft Robotics ◽  
Dual Chamber ◽  
Element Analysis ◽  
Rubber Material ◽  
Single Chamber ◽  
Soft Actuator ◽  
Soft Actuators

As one of the most important characteristics of soft actuators, bending motion has been widely used in the field of soft robotics to perform different manipulation and tasks. In this study, we design silicone rubber material based soft actuators consisting of single and dual chambers, and a bellows structure. Several models of bellows soft actuators were designed, simulated and analyzed using finite element analysis (FEA) software MARC®, in order to understand the characteristics of bellows structured soft actuator with single and dual chambers and to optimize the performance of bending motion of bellows soft actuators. The results confirm that the bellows structured pneumatic soft actuator model 4 of single chamber and model 5 of dual chamber produces the best bending motion and bending angles.

Performance study of RTV-2 Silicone Rubber Material For Soft Actuator by Experimental and Numerical methods: The Effect of Inflation Pressure and Wall Thickness

2020 ◽  
Vol 17 (1) ◽  
pp. 7524-7532 ◽  
Author(s):  
Deepak D. ◽  
Nitesh Kumar ◽  
Shreyas P. Shetty ◽  
Saurabh Jain ◽  
Manoj Bhat
Keyword(s):  
Numerical Methods ◽  
Wall Thickness ◽  
Silicone Rubber ◽  
Inflation Pressure ◽  
Performance Study ◽  
Rubber Material ◽  
Soft Actuator ◽  
Alternative Materials ◽  
Load Carrying ◽  
Influential Parameters

The expensive nature of currently used materials in the soft robotic industry demands the consideration of alternative materials for fabrication. This work investigates the performance of RTV-2 grade silicone rubber for fabrication of a soft actuator. Initially, a cylindrical actuator is fabricated using this material and its performance is experimentally assessed for different pressures. Further, parametric variations of the effect of wall thickness and inflation pressure are studied by numerical methods. Results show that, both wall thickness and inflation pressure are influential parameters which affect the elongation behaviour of the actuator. Thin (1.5 mm) sectioned actuators produced 76.97% more elongation compared to thick sectioned, but the stress induced is 89.61 % higher. Whereas, the thick sectioned actuator (6 mm) showed a higher load transmitting capability. With change in wall thickness from 1.5 mm to 6 mm, the elongation is reduced by 76.97 %, 38.35 %, 21.05 % and 11.43 % at pressure 100 kPa, 75 kPa, 50 kPa and 25 kPa respectively. The induced stress is also found reduced by 89.61 %, 86.66 %, 84.46 % and 68.68 % at these pressures. The average load carrying capacity of the actuator is found to be directly proportional to its wall thickness and inflation pressure.

scholarly journals A Reliable, Label Free Quality Control Method for the Production of DNA Microarrays with Clinical Applications

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 340
Author(s):  
Elisa Chiodi ◽  
Francesco Damin ◽  
Laura Sola ◽  
Lucia Ferraro ◽  
Dario Brambilla ◽  
...  
Keyword(s):  
Quality Control ◽  
Dna Microarrays ◽  
Control Method ◽  
False Negative ◽  
Label Free ◽  
Negative Results ◽  
System A ◽  
Quality Control Method ◽  
False Negative Results ◽  
Imaging Sensor

The manufacture of a very high-quality microarray support is essential for the adoption of this assay format in clinical routine. In fact, poorly surface-bound probes can affect the diagnostic sensitivity or, in worst cases, lead to false negative results. Here we report on a reliable and easy quality control method for the evaluation of spotted probe properties in a microarray test, based on the Interferometric Reflectance Imaging Sensor (IRIS) system, a high-resolution label free technique able to evaluate the variation of the mass bound to a surface. In particular, we demonstrated that the IRIS analysis of microarray chips immediately after probe immobilization can detect the absence of probes, which recognizably causes a lack of signal when performing a test, with clinical relevance, using fluorescence detection. Moreover, the use of the IRIS technique allowed also to determine the optimal concentration of the probe, that has to be immobilized on the surface, to maximize the target recognition, thus the signal, but to avoid crowding effects. Finally, through this preliminary quality inspection it is possible to highlight differences in the immobilization chemistries. In particular, we have compared NHS ester versus click chemistry reactions using two different surface coatings, demonstrating that, in the diagnostic case used as an example (colorectal cancer) a higher probe density does not reflect a higher binding signal, probably because of a crowding effect.

Electrical Insulation Property of Silicone Rubber Tube in High Elevations

2012 ◽  
Vol 503-504 ◽  
pp. 1006-1009
Author(s):  
Guo Min Li ◽  
Chuan Li ◽  
Yun Shui Xu ◽  
Qing Hua Yan ◽  
Shao Quan Zhang ◽  
...  
Keyword(s):  
Silicone Rubber ◽  
High Potential ◽  
Electrical Insulation ◽  
Chain Molecule ◽  
Rubber Tube ◽  
Insulation Property ◽  
Power Frequency ◽  
Test Voltage ◽  
High Elevations ◽  
Potential Test

Silicone rubber is a polymer with the chain molecule structure of Si-O bond [1]. At the environment of 1970 m elevation, the power frequency withstand voltage and condensation experiments will be tested by using two silicone rubber tubes with length of 300mm and 330mm, which lasts one minute, under 85kV. In the high potential test, the silicone rubber tube does not appear the flashover when the surface of tubes weren’t polluted. However, the test voltage increases to 70kV and the surface of the silicone rubber tube will appear flashover, when the tubes are plated in the condensation conditions. The high potential experiments indicate that the electrical insulation property of silicone rubber tube is seriously debated in the humidity environment.

Multiple Inputs-Single Accumulated Output Mechanism for Soft Linear Actuators

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Kyeong Ho Cho ◽  
Ho Moon Kim ◽  
Youngeun Kim ◽  
Sang Yul Yang ◽  
Hyouk Ryeol Choi
Keyword(s):  
Artificial Muscle ◽  
Operating Mode ◽  
Robotic Arm ◽  
Soft Actuator ◽  
Wearable Robots ◽  
Working Principle ◽  
Linear Actuators ◽  
Soft Actuators ◽  
Muscle Actuators ◽  
Further Development

Soft linear actuators (SLAs) such as shape memory alloy (SMA) wires, pneumatic soft actuators, dielectric elastomer actuator, and twisted and coiled soft actuator (TCA) called artificial muscle actuators in general, have many advantages over the conventional actuators. SLAs can realize innovative robotic technologies like soft robots, wearable robots, and bionic arms in the future, but further development is still needed in real applications because most SLAs do not provide large displacement or force as needed. This paper presents a novel mechanism supplementing SLAs by accumulating the displacement of multiple SLAs. It adopts the principle of differential gears in reverse. Since the input units of the mechanism are extensible, more displacement can be accumulated by increasing the number of the input units as many as needed. The mechanism is basically used to accumulate displacements, but can be used to accumulate forces by changing its operating mode. This paper introduces the design and working principle of the mechanism and validates its operation experimentally. In addition, the mechanism is implemented on a robotic arm and its effectiveness is confirmed.

Examining the Coiling Motion of Soft Actuators Reinforced With Tilted Helix Fibers

2018 ◽  
Author(s):  
Ryan Geer ◽  
Suyi Li
Keyword(s):  
Longitudinal Axis ◽  
Robotic Manipulation ◽  
Proof Of Concept ◽  
Soft Actuator ◽  
Kevlar Fiber ◽  
New Family ◽  
End Caps ◽  
Soft Actuators ◽  
Unique Cell ◽  
Cell Wall Architecture

This study aims to examine the coiling and uncoiling motion of a soft pneumatic actuator reinforced with tilted helix fibers. Coiling motion can be quite useful for robotic manipulation and locomotion purposes. This research proposes and investigates a novel actuator that is inspired and derived from the unique cell wall architecture in the seed appendage of Stork’s Bill plant (Erodium Gruinum). These plant cells are reinforced by cellulose fibers distributed in a tilted helix pattern — helixes that are tilted at a certain angle with respect to the longitudinal axis of the cell. As a result, the seed appendage can coil and uncoil via a combination of twisting and bending. This paper discusses the design, fabrication, and testing of a soft actuator that can mimic this sophisticated motion. This actuator consists of Kevlar fiber thread wrapped around a silicon rubber body that has the shape of a tube. The tube will be capped at both ends so that it can be pressurized internally to induce motion. Once the design parameter has been chosen, the soft actuator are fabricated by 1) designing and 3D printing molds, 2) tube casting and fiber wrapping, and 3) creating the end caps for pressure sealing. Carefully executing these fabrication steps is essential because any errors could give undesired deformation. Several soft actuators prototypes are fabricated based on different design choices regarding the actuator radius, tube wall thickness, and the number of tilted helix fibers (aka. fiber coverage). Proof-of-concept tests show that these actuator prototypes can indeed exhibit a combined twisting and bending under internal pressurization: all are the necessary receipts to achieve the coiling and uncoiling motion. Result of this paper can pave the way for a new family of soft actuators capable of unprecedented and sophisticated actuation motions, which are particularly appealing for soft robot application.

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