Design of a Compliant Industrial Gripper Driven by a Bistable Shape Memory Alloy Actuator

2020 ◽  
Author(s):  
Dominik Scholtes ◽  
Stefan Seelecke ◽  
Gianluca Rizzello ◽  
Paul Motzki
Keyword(s):  
Shape Memory ◽  
High Energy ◽  
Industrial Applications ◽  
High Energy Density ◽  
Small Scale ◽  
Monitoring And Control ◽  
Actuation System ◽  
First Results ◽  
Functional Prototype ◽  
And Control

Abstract Within industrial manufacturing most processing steps are accompanied by transporting and positioning of workpieces. The active interfaces between handling system and workpiece are industrial grippers, which often are driven by pneumatics, especially in small scale areas. On the way to higher energy efficiency and digital factories, companies are looking for new actuation technologies with more sensor integration and better efficiencies. Commonly used actuators like solenoids and electric engines are in many cases too heavy and large for direct integration into the gripping system. Due to their high energy density shape memory alloys (SMA) are suited to overcome those drawbacks of conventional actuators. Additionally, they feature self-sensing abilities that lead to sensor-less monitoring and control of the actuation system. Another drawback of conventional grippers is their design, which is based on moving parts with linear guides and bearings. These parts are prone to wear, especially in abrasive environments. This can be overcome by a compliant gripper design that is based on flexure hinges and thus dispenses with joints, bearings and guides. In the presented work, the development process of a functional prototype for a compliant gripper driven by a bistable SMA actuation unit for industrial applications is outlined. The focus lies on the development of the SMA actuator, while the first design approach for the compliant gripper mechanism with solid state joints is proposed. The result is a working gripper-prototype which is mainly made of 3D-printed parts. First results of validation experiments are discussed.

scholarly journals A Review of Propulsion, Power, and Control Architectures for Insect-Scale Flapping-Wing Vehicles

2018 ◽  
Vol 70 (1) ◽  
Author(s):  
E. Farrell Helbling ◽  
Robert J. Wood
Keyword(s):  
Integrated Circuit ◽  
Micro Air Vehicles ◽  
High Energy ◽  
Flapping Wing ◽  
High Energy Density ◽  
Small Scale ◽  
Flying Insects ◽  
Power And Control ◽  
Recent Developments ◽  
And Control

Flying insects are able to navigate complex and highly dynamic environments, can rapidly change their flight speeds and directions, are robust to environmental disturbances, and are capable of long migratory flights. However, flying robots at similar scales have not yet demonstrated these characteristics autonomously. Recent advances in mesoscale manufacturing, novel actuation, control, and custom integrated circuit (IC) design have enabled the design of insect-scale flapping wing micro air vehicles (MAVs). However, there remain numerous constraints to component technologies—for example, scalable high-energy density power storage—that limit their functionality. This paper highlights the recent developments in the design of small-scale flapping wing MAVs, specifically discussing the various power and actuation technologies selected at various vehicle scales as well as the control architecture and avionics onboard the vehicle. We also outline the challenges associated with creating an integrated insect-scale flapping wing MAV.

Simulation of Mechanical Behavior of NiTi Shape Memory Alloys Under Complex Loading: Model Formulation and its Performance in Applications

2014 ◽  
Author(s):  
Petr Sedlák ◽  
Miroslav Frost ◽  
Alena Kruisová ◽  
Petr Šittner ◽  
Luděk Heller
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Complex Loading ◽  
Transformation Strain ◽  
High Energy ◽  
High Energy Density ◽  
Proportional Loading ◽  
Strain Anisotropy ◽  
Loading Mode ◽  
And Control

Actuators in the form of a helical spring made from shape memory alloy are attractive due to light weight, large recoverable deformation, high energy density and manufacturing simplicity. For their optimal design and control detailed information on evolution of phase and stress distribution within the material during operation is advantageous. In this work a constitutive model tailored for non-proportionally loaded shape memory alloys exhibiting R-phase transition, transformation strain anisotropy, tension-compression asymmetry is employed to reveal and interpret relation between macroscopic response of such an actuator and microscopic state within the shape memory material. Numerical simulations confirm good predictive capability of the model and demonstrate that because of naturally non-proportional loading mode, phase and stress distributions within cross-section of the wire may be rather complex and counterintuitive.

Design and Control of Chemomuscle: A Liquid-Propellant-Powered Muscle Actuation System

2011 ◽  
Vol 133 (2) ◽  
Author(s):  
Xiangrong Shen ◽  
Daniel Christ
Keyword(s):  
Liquid Fuel ◽  
Artificial Muscle ◽  
High Energy ◽  
Mobile Systems ◽  
High Energy Density ◽  
Effective Control ◽  
Future Application ◽  
Actuation System ◽  
Highly Nonlinear ◽  
And Control

This paper describes the design and control of a new chemomuscle actuation system for robotic systems, especially the mobile systems inspired by biological principles. Developed based on the pneumatic artificial muscle, a chemomuscle actuation system features a high power density, as well as similar characteristics to the biological muscles. Furthermore, by introducing monopropellant (a special type of liquid fuel) as the energy storage media, the chemomuscle system leverages the high energy density of liquid fuel and provides a compact form of high-pressure gas supply with a simple structure. The introduction of monopropellant addresses the limitation of pneumatic supply on mobile devices and thus is expected to facilitate the future application of artificial muscle on biorobotic systems. In this paper, the design of a chemomuscle actuation system is presented, as well as a robust controller design that provides effective control for this highly nonlinear system. To demonstrate the proposed chemomuscle actuation system, an experimental prototype is constructed, on which the proposed control algorithm provides good tracking performance.

scholarly journals Current Knowledge and Future Directions for Improving Subsoiling Quality and Reducing Energy Consumption in Conservation Fields

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 575
Author(s):  
Shangyi Lou ◽  
Jin He ◽  
Hongwen Li ◽  
Qingjie Wang ◽  
Caiyun Lu ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Cover Crops ◽  
Current Knowledge ◽  
High Energy ◽  
Field Application ◽  
Research Progress ◽  
Monitoring And Control ◽  
Future Directions ◽  
Tillage Depth ◽  
And Control

Subsoiling has been acknowledged worldwide to break compacted hardpan, improve soil permeability and water storage capacity, and promote topsoil deepening and root growth. However, there exist certain factors which limit the wide in-field application of subsoiling machines. Of these factors, the main two are poor subsoiling quality and high energy consumption, especially the undesired tillage depth obtained in the field with cover crops. Based on the analysis of global adoption and benefits of subsoiling technology, and application status of subsoiling machines, this article reviewed the research methods, technical characteristics, and developing trends in five key aspects, including subsoiling shovel design, anti-drag technologies, technologies of tillage depth detection and control, and research on soil mechanical interaction. Combined with the research progress and application requirements of subsoiling machines across the globe, current problems and technical difficulties were analyzed and summarized. Aiming to solve these problems, improve subsoiling quality, and reduce energy consumption, this article proposed future directions for the development of subsoiling machines, including optimizing the soil model in computer simulation, strengthening research on the subsoiling mechanism and comprehensive effect, developing new tillage depth monitoring and control systems, and improving wear-resisting properties of subsoiling shovels.

scholarly journals A Compact Review of Laser Welding Technologies for Amorphous Alloys

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1690
Author(s):  
Jian Qiao ◽  
Peng Yu ◽  
Yanxiong Wu ◽  
Taixi Chen ◽  
Yixin Du ◽  
...  
Keyword(s):  
Amorphous Alloy ◽  
Laser Welding ◽  
Amorphous Alloys ◽  
High Energy ◽  
Industrial Applications ◽  
High Energy Density ◽  
Current Status ◽  
Future Research ◽  
Technological Parameters ◽  
Fast Heating

Amorphous alloys have emerged as important materials for precision machinery, energy conversion, information processing, and aerospace components. This is due to their unique structure and excellent properties, including superior strength, high elasticity, and excellent corrosion resistance, which have attracted the attention of many researchers. However, the size of the amorphous alloy components remains limited, which affects industrial applications. Significant developments in connection with this technology are urgently needed. Laser welding represents an efficient welding method that uses a laser beam with high energy-density for heating. Laser welding has gradually become a research hotspot as a joining method for amorphous alloys due to its fast heating and cooling rates. In this compact review, the current status of research into amorphous-alloy laser welding technology is discussed, the influence of technological parameters and other welding conditions on welding quality is analyzed, and an outlook on future research and development is provided. This paper can serve as a useful reference for both fundamental research and engineering applications in this field.

High-Energy-Density Shape Memory Materials with Ultrahigh Strain for Reconfigurable Artificial Muscles

2021 ◽  
Author(s):  
Zheng Xu ◽  
Yujie Chen ◽  
Chi Chen ◽  
Zhen Chen ◽  
Yu Tong Guo ◽  
...  
Keyword(s):  
Energy Density ◽  
Shape Memory ◽  
High Energy ◽  
High Energy Density ◽  
Soft Robotics ◽  
Artificial Muscles ◽  
Flexible Devices ◽  
Shape Memory Materials ◽  
Ultrahigh Strain ◽  
Considerable Strain

Abstract Programmable and reconfigurable artificial muscles are highly promising and desirable for applications, including soft robotics, flexible devices, and biomedical devices. However, the combination of considerable strain and high energy...

Design Framework for Multi-Section Shape Memory Alloy Axial Actuators Considering Material and Geometric Uncertainties

2020 ◽  
Author(s):  
Weilin Guan ◽  
Edwin A. Peraza Hernandez
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
High Energy ◽  
High Energy Density ◽  
Design Framework ◽  
Efficient Design ◽  
Cross Sectional ◽  
Geometric Uncertainties ◽  
In Series ◽  
The Wire

Abstract Shape memory alloys are metallic materials with the capability of performing as high energy density actuators driven by temperature control. This paper presents a design framework for shape memory alloy (SMA) axial actuators composed of multiple wire sections connected in series. The various wire sections forming the actuators can have distinct cross-sectional areas and lengths, which can be modulated to adjust the overall thermomechanical response of the actuator. The design framework aims to find the optimal cross-sectional areas and lengths of the wire sections forming the axial actuator such that its displacement vs. temperature actuation path approximates a target path. Constraints on the length-to-diameter aspect ratio and stress of the wire sections are incorporated. A reduced-order numerical model for the multi-section SMA actuators that allows for efficient design evaluations is derived and implemented. An approach to incorporate uncertainty in the geometry and material parameters of the actuators within the design framework is implemented to allow for the determination of robust actuator designs. A representative application example of the design framework is provided illustrating the benefits of using multiple wire sections in axial actuators to modulate their overall response and approximate a target displacement vs. temperature actuation path.

scholarly journals A new active asymmetry monitoring and control technique applied to critical aircraft flap control system failures

2019 ◽  
Vol 304 ◽  
pp. 04011
Author(s):  
Dario Belmonte ◽  
Matteo Davide Lorenzo Dalla Vedova ◽  
Gaetano Quattrocchi
Keyword(s):  
Control System ◽  
Flight Control ◽  
Angular Position ◽  
Control Technique ◽  
Monitoring And Control ◽  
Active Monitoring ◽  
Actuation System ◽  
Left And Right ◽  
And Control ◽  
Current Monitoring

Asymmetry limitation requirements between left and right wing flap surfaces play an important role in the design of the implementation of the secondary flight control system of modern airplanes. In fact, especially in the case of sudden breaking of one of the torsion bars of the flap transmission line, the huge asymmetries that can rapidly develop could compromise the lateral-directional controllability of the whole aircraft (up to cause catastrophic occurrences). Therefore, in order to guarantee the aircraft safety (especially during take-off and landing flight phase in which the effects of asymmetries could generate uncontrollable aircraft attitudes), it is mandatory to timely detect and neutralize these asymmetries. The current monitoring techniques generally evaluate the differential angular position between left and right surfaces and, in most the events, limit the Flaps Control System (FCS) asymmetries, but in severe fault conditions (e.g. under very high aerodynamic loads), unacceptable asymmetries could be generated, compromising the controllability of the aircraft. To this purpose, in this paper the authors propose a new active monitoring and control technique capable of detecting the increasing angular error between the different flap surfaces and that, after stopping the whole actuation system, acts on the portion of the actuation line still connected to the PDU to minimize the FCS asymmetries.

scholarly journals Diffusion and radiation in magnetized collisionless plasmas with small-scale Whistler turbulence

2016 ◽  
Vol 82 (2) ◽  
Author(s):  
Brett D. Keenan ◽  
Mikhail V. Medvedev
Keyword(s):  
Numerical Study ◽  
High Energy ◽  
High Energy Density ◽  
Larmor Radius ◽  
Small Scale ◽  
Collisionless Plasmas ◽  
Correlation Scale ◽  
Scale Turbulence ◽  
Solar Plasmas ◽  
High Energy Density Plasmas

Magnetized high-energy-density plasmas can often have strong electromagnetic fluctuations whose correlation scale is smaller than the electron Larmor radius. Radiation from the electrons in such plasmas – which markedly differs from both synchrotron and cyclotron radiation – is tightly related to their energy and pitch-angle diffusion. In this paper, we present a comprehensive theoretical and numerical study of particle transport in cold, ‘small-scale’ Whistler-mode turbulence and its relation to the spectra of radiation simultaneously produced by these particles. We emphasize that this relation is a superb diagnostic tool of laboratory, astrophysical, interplanetary and solar plasmas with a mean magnetic field and strong small-scale turbulence.

Sign in / Sign up

Export Citation Format

Share Document