Large Stroke Comb-Drive Actuators Using Reinforced, Clamped, Paired Double Parallelogram (C-DP-DP) Flexure

2012 ◽  
Author(s):  
Mohammad Olfatnia ◽  
Siddharth Sood ◽  
Shorya Awtar
Keyword(s):  
Large Range ◽  
Actuation Voltage ◽  
Design Procedure ◽  
Experimental Measurements ◽  
Beam Length ◽  
Comb Drive ◽  
Motion Direction ◽  
Micro Fabrication ◽  
Flexure Mechanism ◽  
The Individual

This paper reports in-plane electrostatic comb-drive actuators with stroke as large as 245 μm, achieved by employing a novel Clamped Paired Double Parallelogram (C-DP-DP) flexure mechanism. For a given flexure beam length (L1), comb gap (G), and actuation voltage (V), this is currently the largest comb-drive actuator stroke reported in the literature. The C-DP-DP flexure mechanism design offers high bearing direction stiffness (Kx) while maintaining low motion direction stiffness (Ky), over a large range of motion direction displacement. The resulting high (Kx /Ky) ratio mitigates the on-set of sideways snap-in instability, thereby offering significantly greater actuation stroke compared to existing designs. Further improvement is achieved by reinforcing the individual beams in this flexure mechanism. While the traditional Paired Double Parallelogram (DP-DP) flexure design with G = 3 μm, L1 = 1 mm results in a 50 μm stroke before snap-in, the reinforced C-DP-DP design with G = 3μm achieves a stroke of 141 μm. The same C-DP-DP flexure design provides a 215 μm stroke with G = 4 μm, and a 245 μm stroke with G = 6 μm. The presented work includes closed-form stiffness values for the reinforced C-DP-DP flexure, a design procedure for selecting dimensions of the overall comb-drive actuator, micro-fabrication of some representative actuators, and experimental measurements demonstrating the large stroke.

MEMS Based XY Stage With Large Displacement

2013 ◽  
Author(s):  
Mohammad Olfatnia ◽  
Leqing Cui ◽  
Pankaj Chopra ◽  
Shorya Awtar
Keyword(s):  
Degrees Of Freedom ◽  
Large Range ◽  
Comb Drive ◽  
Motion Direction ◽  
Stage Design ◽  
Single Degree Of Freedom ◽  
Stiffness Analysis ◽  
Single Degree ◽  
Motion Stage ◽  
Finite Elements Simulation

This paper presents a micro XY stage that employs electrostatic comb-drive actuators and achieves a bi-directional displacement range greater than 225 μm per motion axis. The proposed XY stage design comprises four rigid stages (ground, motion stage, and two intermediate stages) interconnected via flexure modules. The motion stage, which has two translational degrees of freedom, is connected to two independent single degree of freedom intermediate stages via respective parallelogram (P) transmission flexures. The intermediate stages are connected to the ground via respective Clamped paired Double Parallelogram (C-DP-DP) guidance flexures. The C-DP-DP flexure, unlike conventional flexures such as the paired Double Parallelogram flexure (DP-DP), provides high bearing direction stiffness (Kb) while maintaining low motion direction stiffness (Km) over a large range of motion direction displacement. This helps delay the onset of sideways instability in the comb-drive actuators that are integrated with the intermediate stages, thereby offering significantly greater actuation stroke compared to existing designs. The presented work includes closed-form stiffness analysis of the proposed micro XY stage, finite elements simulation, and experimental measurements of its static and dynamic behavior.

Experimental Characterization of a Large-Range Parallel Kinematic XYZ Flexure Mechanism

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Shorya Awtar ◽  
Jason Quint ◽  
John Ustick
Keyword(s):  
Degrees Of Freedom ◽  
Large Range ◽  
Experimental Setup ◽  
Modular Construction ◽  
Finite Elements Analysis ◽  
Motion Direction ◽  
Flexure Mechanism ◽  
Parallel Kinematic ◽  
Cross Axis ◽  
Exact Constraint

Abstract Previously, we reported the conceptual design of a novel parallel-kinematic flexure mechanism that provides large and decoupled motions in the X, Y, and Z directions, along with good actuator isolation, and small parasitic error motions (Awtar, S., Ustick, J., and Sen, S., 2012, “An XYZ Parallel-Kinematic Flexure Mechanism With Geometrically Decoupled Degrees of Freedom,” ASME J. Mech. Rob., 5(1), p. 015001). This paper presents the detailed design and fabrication of a high-precision experimental setup to characterize and validate the motion attributes of this proposed flexure design via comprehensive measurements. The unique aspects of this experimental setup include a novel modular construction and exact-constraint assembly of the flexure mechanism from 12 identical parallelogram flexure modules. The flexure mechanism along with the sensing and actuation setup in the experiment is designed to enable large range (10 mm) in each direction. Experimental measurements and finite-elements analysis demonstrate <3% variation in motion direction stiffness, 20.4% lost motion, <11.6% cross-axis error, <3.3% actuator isolation, and <9.5 mrad motion stage rotation over the entire 10 mm × 10 mm × 10 mm range of motion.

Design of a Large Range XY Nanopositioning System

2010 ◽  
Author(s):  
Shorya Awtar ◽  
Gaurav Parmar
Keyword(s):  
Physical System ◽  
Large Range ◽  
Test Results ◽  
Flexure Mechanism ◽  
Motion Range ◽  
Parallel Kinematic ◽  
Large Motion ◽  
The Individual ◽  
High Degree ◽  
Motion Quality

Achieving large motion range (> 1 mm) along with nanometric motion quality (< 10 nm), simultaneously, has been a key challenge in nanopositioning systems. Practical limitations associated with the individual physical components (flexure bearing, actuators, and sensors) and their integration, particularly in the case of multi-axis systems, have restricted the range of current nanopositioning systems to about 100 μm. This paper presents a novel physical system layout, with a parallel-kinematic XY flexure mechanism at its heart, that provides a high degree of decoupling between the two motion axes by avoiding geometric over-constraints, provides actuator isolation that allows the use of large-stroke single-axis actuators, and enables a complementary end-point sensing scheme that employs commonly available sensors. These attributes help achieve an unprecedented 10 mm × 10 mm motion range in the proposed nanopositioning system. Having overcome the physical system design challenges, a dynamic model of proposed nanopositioning system is created and verified via system identification methods. In particular, dynamic non-linearities associated with the large displacements of the flexure mechanism and resulting controls challenges are identified. The physical system is fabricated, assembled, and tested to validate its simultaneous large range and nanometric motion capabilities. Preliminary closed-loop test results, which highlight the potential of this new design configuration, are presented.

Design of a Large Range XY Nanopositioning System

2013 ◽  
Vol 5 (2) ◽  
Author(s):  
Shorya Awtar ◽  
Gaurav Parmar
Keyword(s):  
Physical System ◽  
Large Range ◽  
Test Results ◽  
Flexure Mechanism ◽  
Motion Range ◽  
Parallel Kinematic ◽  
Large Motion ◽  
The Individual ◽  
High Degree ◽  
Motion Quality

Achieving large motion range (>1 mm) along with nanometric motion quality (<10 nm) simultaneously has been a key challenge in nanopositioning systems. Practical limitations associated with the individual physical components (bearing, actuators, and sensors) and their integration, particularly in the case of multi-axis systems, have restricted the range of currently available nanopositioning systems to approximately 100 μm per axis. This paper presents a novel physical system layout, comprising a bearing, actuators, and sensors, that enables large range XY nanopositioning. The bearing is based on a parallel-kinematic XY flexure mechanism that provides a high degree of geometric decoupling between the two motion axes by avoiding geometric over-constraint, provides actuator isolation that allows the use of large-stroke single-axis actuators, and enables a complementary end-point sensing scheme using commonly available sensors. These attributes help achieve 10 mm × 10 mm motion range in the proposed nanopositioning system. Having overcome the physical system design challenges, a dynamic model of the proposed nanopositioning system is created and verified via system identification. In particular, dynamic nonlinearities associated with the large displacements of the flexure mechanism and resulting controls challenges are identified. The physical system is fabricated, assembled, and tested to validate its simultaneous large range and nanometric motion capabilities. Preliminary closed-loop test results, which highlight the potential as well as pending challenges associated with this new design configuration, are presented.

An XYZ Parallel Kinematic Flexure Mechanism With Geometrically Decoupled Degrees of Freedom

2011 ◽  
Author(s):  
Shorya Awtar ◽  
John Ustick ◽  
Shiladitya Sen
Keyword(s):  
Degrees Of Freedom ◽  
Element Analysis ◽  
Motion Direction ◽  
Form Analysis ◽  
Flexure Mechanism ◽  
Non Linear ◽  
Decoupled Motion ◽  
Motion Range ◽  
Parallel Kinematic ◽  
Cross Axis

We present the constraint-based design of a novel parallel kinematic flexure mechanism that provides highly decoupled motions along the three translational directions (X, Y, and Z) and high stiffness along the three rotational directions (θx, θy, and θz). The geometric decoupling ensures large motion range along each translational direction and enables integration with large-stroke ground-mounted linear actuators or generators, depending on the application. The proposed design, which is based on a systematic arrangement of multiple rigid stages and parallelogram flexure modules, is analyzed via non-linear finite element analysis. A proof-of-concept prototype of the flexure mechanism is fabricated to validate its large range and decoupled motion capability. The analyses as well as the hardware demonstrate an XYZ motion range of 10 mm × 10 mm × 10 mm. Over this motion range, the non-linear FEA predicts a cross-axis error of less than 3%, parasitic rotations less than 2 mrad, less than 4% lost motion, actuator isolation less than 1.5%, and no perceptible motion direction stiffness variation. Ongoing work includes non-linear closed-form analysis and experimental measurement of these error motion and stiffness characteristics.

An XYZ Parallel-Kinematic Flexure Mechanism With Geometrically Decoupled Degrees of Freedom

2012 ◽  
Vol 5 (1) ◽  
Author(s):  
Shorya Awtar ◽  
John Ustick ◽  
Shiladitya Sen
Keyword(s):  
Degrees Of Freedom ◽  
Finite Elements Analysis ◽  
Motion Direction ◽  
Flexure Mechanism ◽  
Nonlinear Finite Elements ◽  
Decoupled Motion ◽  
Motion Range ◽  
Stiffness Variation ◽  
Parallel Kinematic ◽  
Cross Axis

A novel parallel-kinematic flexure mechanism that provides highly decoupled motions along the three translational directions (X, Y, and Z) and high stiffness along the three rotational directions (θx, θy, and θz) is presented. Geometric decoupling ensures large motion range along each translational direction and enables integration with large-stroke ground-mounted linear actuators or generators, depending on the application. The proposed design, which is based on a systematic arrangement of multiple rigid stages and parallelogram flexure modules, is analyzed via nonlinear finite elements analysis (FEA). A proof-of-concept prototype is fabricated to validate the predicted large range and decoupled motion capabilities. The analysis and the hardware prototype demonstrate an XYZ motion range of 10 mm × 10 mm × 10 mm. Over this motion range, the nonlinear FEA predicts cross-axis errors of less than 7.8%, parasitic rotations less than 10.8 mrad, less than 14.4% lost motion, actuator isolation better than 1.5%, and no perceptible motion direction stiffness variation.

Designing a Compact Wireless Network Based Device-Free Passive Localisation System for Indoor Environments

2018 ◽  
pp. 1424-1439
Author(s):  
Philip Vance ◽  
Girijesh Prasad ◽  
Jim Harkin ◽  
Kevin Curran
Keyword(s):  
Assisted Living ◽  
Ambient Assisted Living ◽  
Design Procedure ◽  
The Elderly ◽  
Healthcare Services ◽  
Indoor Environments ◽  
Signal Processing Technique ◽  
Minimum Number ◽  
The Individual ◽  
Device Free

Determining the location of individuals within indoor locations can be useful in various scenarios including security, gaming and ambient assisted living for the elderly. Healthcare services globally are seeking to allow people to stay in their familiar home environments longer due to the multitude of benefits associated with living in non-clinical environments and technologies to determine an individual's movements are key to ensuring that home emergencies are detected through lack of movement can be responded to promptly. This paper proposes a device-free localisation (DFL) system which would enable the individual to proceed with normal daily activities without the concern of having to wear a traceable device. The principle behind this is that the human body absorbs/reflects the radio signal being transmitted from a transmitter to one or more receiving stations. The proposed system design procedure facilitates the use of a minimum number of wireless nodes with the help of a principle component analysis (PCA) based intelligent signal processing technique. Results demonstrate that human detection and tracking are possible to within 1m resolution with a minimal hardware infrastructure.

scholarly journals Design of a Novel Modular Axial-Flux Double Rotor Switched Reluctance Drive

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1161 ◽  
Author(s):  
Pere Andrada ◽  
Balduí Blanqué ◽  
Eusebi Martínez ◽  
José Ignacio Perat ◽  
José Antonio Sánchez ◽  
...  
Keyword(s):  
Design Procedure ◽  
Experimental Measurements ◽  
Axial Flux ◽  
Element Analysis ◽  
Switched Reluctance ◽  
Flux Reversal ◽  
Switched Reluctance Machines ◽  
Output Torque ◽  
Rotor Poles ◽  
New Distribution

Nowadays, there is a renewed interest in switched reluctance machines and especially in axial-flux switched reluctance machines (AFSRM). This paper presents a comprehensive design procedure for modular AFSRM with an inner stator and two exterior rotors that have a new distribution of the stator and rotor poles, resulting in short magnetic paths with no flux reversal. After a description of the proposed machine, the output torque equation is derived from a simplified non-linear energy conversion loop and guidelines for its design are given. Once the preliminary sizing has been carried out the different modules of the AFSRM, the magnetically active parts made with SMC, are reshaped or refined using 3D printing and 3D electromagnetic finite element analysis until they reach their definitive shape and dimensions. Finally, an AFSRM has been built following the proposed design procedure and has been validated by experimental measurements.

Young’s Modulus of Nanohoneycomb Structures According to the Porosity

2007 ◽  
Vol 334-335 ◽  
pp. 761-764
Author(s):  
D.H. Choi ◽  
C.W. Lee ◽  
P.S. Lee ◽  
J.H. Lee ◽  
W. Hwang ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Young’S Modulus ◽  
Large Range ◽  
Young's Modulus ◽  
Vertical Direction ◽  
Moment Of Inertia ◽  
Beam Length ◽  
Bending Tests ◽  
Force Microscopy ◽  
Atomic Force

Young’s modulus of nanohoneycomb structures in the vertical direction relative to the pore (generally along the beam length) is measured according to the porosity from bending tests in atomic force microscopy (AFM). The pore diameters of the nanohoneycomb structures are from about 30 to 60 nm. To determine the Young’s modulus of the nanohoneycomb structures, the area moment of inertia of the nanohoneycomb structure is determined according to the arrangement of the pores. The area moment of inertia of the nanohoneycomb structure is found to be affected by the porosity of the nanohoneycomb structures. The Young’s modulus of the nanohoneycomb structures decreases as a function of the porosity in a large range.

scholarly journals Design of lubrication system, design of motor bed, selecting of propeller for aircraft piston engine

2021 ◽  
Author(s):  
Michal Suk ◽  
◽  
Jozef Čerňan
Keyword(s):  
System Design ◽  
Design Procedure ◽  
Aircraft Engine ◽  
Scientific Article ◽  
Lubrication System ◽  
Piston Engine ◽  
Safety Requirements ◽  
Technical Requirements ◽  
Different Types ◽  
The Individual

I will briefly address the three orientations of my paper in this scientific article. I will not go into details in the article. In the first part I will briefly describe the design procedure of a piston engine lubrication system, the requirements that a lubrication system should meet with respect to different types of piston engines and their focus, elements of the lubrication system and the properties of oils as lubricating fluids.In the next part I will describe the types and constructions of aircraft engine beds, technical requirements for aircraft engine beds and individual loads that the aircraft engine bed must withstand. In the last part I will focus on aircraft propellers. I will explain the basic principle of the propeller, the individual rules for selecting a propeller for a piston engine, safety requirements for an aircraft propeller and the dividing of basic types of aircraft propellers for aircraft piston engines.

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