A dual reflector system with a reconformable subreflector

Viskum, H.-H.; Sørensen, Stig B.; Pontoppidan, K.

doi:10.1109/aps.1998.702069

Cited by 4 publications

(3 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the past few decades a number of investigations were performed to create a mechanically reconfigurable reflector. [3][4][5][6][7][8][9][10][11][12][13][14][15] In the pioneering works of Prof. P.J.B. Clarricoats, 4-7 the reshaping of a rim supported metal tricot mesh surface was investigated.…”

Section: Introductionmentioning

confidence: 99%

Design of a Morphing Skin Using Flexible Fiber Composites for Space-Reconfigurable Reflectors

Datashvili

Baier

Wei

et al. 2013

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

View full text Add to dashboard Cite

A number of aerospace structural applications with intended shape variation require different kinds of morphing skins for fulfillment of diverse requirements. An example of such a morphing skin application is a space-reconfigurable reflector antenna of a telecommunication satellite. Reconfigurable reflectors can replace the typical configuration of several shaped reflectors and satellites with a single reflector and, thereby, enhance coverage performance to several needed areas of the Earth during a single lifetime in orbit. Thus, their application promises huge cost savings. Design of the reflector morphing skin, being a focus of the paper, is a challenging task because besides the ability to morph they have to satisfy mechanical and radio frequency stringent requirements. Material selection, tailoring of the material properties based on numerical and experimental studies, improving radio frequency characteristics and deriving the potential concept of the mechanically reconfigurable reflector are addressed in the paper. Reshaping performance is discussed based on comparison of target and achieved shapes. Final achieved shapes are acquired with an established optimization procedure coupling RF and structural behaviors. Nomenclature  ABD = Stiffness matrix of a laminate, A in plane, D bending and B coupling parts  = Vector of strains  = Vector of curvatures = Tensile modulus G = Shear modulus = Poisson ratio = Laminate thickness = Ratio of banding stiffness to shear stiffness

show abstract

Section: Introductionmentioning

confidence: 99%

Design of a Morphing Skin Using Flexible Fiber Composites for Space-Reconfigurable Reflectors

Datashvili

Baier

Wei

et al. 2013

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

View full text Add to dashboard Cite

show abstract

“…There are a wide variety of design methods that have been developed for active antenna structures. For example, a two-axis gimbal system can be used to enable steering of the antenna structure (Viskum et al, 1998), or an adaptive array, which uses a variety of electrical components, can be used to modify the operating characteristics of the antenna (Washington and Silverberg, l995). However, both of these options are often cost prohibitive.…”

Section: Introductionmentioning

confidence: 99%

Modeling and Control of a Singly Curved Active Aperture Antenna Using Curved Piezoceramic Actuators

Granger

Washington

Kwak

2000

Journal of Intelligent Material Systems and Structures

View full text Add to dashboard Cite

There is an increasing need for aperture antenna devices that incorporate multifunctional capability. One popular solution to this problem is the use of an “active aperture antenna” that is able to vary the direction and shape of its radiation pattern by using actuators to alter the shape of the reflector. This study focuses on the use of a pre-curved piezoceramic actuator, referred to as a THUNDER actuator, to change the shape of a prototype reflector. These actuators offer greater force, deflection and higher strength than traditional PZT actuators, while maintaining cost effectiveness. In this study the design of a prototype antenna structure that can accommodate deflection experiments and far-field radiation pattern tests is presented. The theoretical relationship between the dish deflection and the input voltage is established in two stages. In the first stage, the deflection at the end of the actuator is determined using a combination of Hamilton’s principle and laminated composite curved beam theory. The piezoelectric properties of the actuator are also considered during this stage. In the second stage, the deflection at the tip of the dish is calculated using geometric relationships, with the assumption that the remaining portion of the dish moves as a rigid body. The resulting deflection equations yield results that closely match the experimental quasi-static deflection results for a given input voltage, despite the presence of hysteresis. A dynamic model for a THUNDER actuator is developed based on experimental frequency response measurements. Positive Positioned Feedback (PPF) control is implemented on the system, in order to reduce position overshoot and oscillations in the transient response of the structure. The controller yields an improvement in the transient response in both simulation and experiments. Finally, the controlled system is utilized to transmit radiation in the far field.

show abstract

“…Such systems are of interest also for special applications, such as compact range antennas [1], feeding structures for very large radio telescopes [2,3], reconfigurable reflectors [4,5]. During the years, a large number of dual reflector synthesis techniques have been introduced in order to design reflector geometries and feeding structures allowing to satisfy "at the best" the far-field pattern requirements.…”

Section: Introductionmentioning

confidence: 99%

An Effective Power Synthesis Technique for Shaped, Double-Reflector Multifeed Antennas

Bucci¹,

Capozzoli²,

D'Elia³

2003

PIER

View full text Add to dashboard Cite

Abstract-A new synthesis algorithm for shaped, double-reflector antennas with complex array feed is presented.The approach presented here aims to improve the efficiency of synthesis techniques without missing the required accuracy. The algorithm is based on a convenient splitting of the original problem into two phases, each one involving a sub-problem significantly simpler than the original one.A double reflector synthesis problem involving only Fourier Transform (FT) operators is of concern during the first phase. The subreflector surface and a first estimate of the main reflector geometry are obtained in this step. A single reflector synthesis problem is considered during the second phase wherein the final main reflector surface and the excitation coefficients of the primary feed array are obtained. While in the first phase only approximate relationships between the unknowns and the secondary radiated field are exploited, in the second phase accurate radiation operators are involved. Despite this accuracy, the second phase is still numerically effective since it involves a single reflector synthesis problem and exploits, as "good" starting point, the main reflector estimate obtained during the first phase.The effectiveness of the approach is due to the fact that the necessity of dealing simultaneously with two reflector surfaces, the key of the synthesis difficulties, is afforded only during the first phase where efficient computational tools are allowed.A numerical example shows the effectiveness of the proposed approach.

show abstract

A dual reflector system with a reconformable subreflector

Cited by 4 publications

References 1 publication

Design of a Morphing Skin Using Flexible Fiber Composites for Space-Reconfigurable Reflectors

Design of a Morphing Skin Using Flexible Fiber Composites for Space-Reconfigurable Reflectors

Modeling and Control of a Singly Curved Active Aperture Antenna Using Curved Piezoceramic Actuators

An Effective Power Synthesis Technique for Shaped, Double-Reflector Multifeed Antennas

Contact Info

Product

Resources

About