High precision automated alignment procedure for two-mirror telescopes

Hampson, Karen M.; Gooding, David; Cole, R. J.; Booth, Martin J.

doi:10.1364/ao.58.007388

Cited by 13 publications

(10 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…7 This method of sequential DoF alignment cannot fully account for coupling between DoF, which may necessitate requiring multiple iterations of the entire sequence to correct residual errors. 8 The SHWFS was investigated as a potential wavefront sensing instrument as it has many additional capabilities required for in-orbit alignment. In the Deformable Mirror Demonstration Mission, a SHWFS passed space condition environmental testing, survived launch, and is in operation.…”

Section: Shack-hartmann Wavefront Sensormentioning

confidence: 99%

“…In a multi-input optical system, a set of functions which relate the Zernike coefficients a(t) to the positioning of the optical components C(t) can be found; 6,8 these are the so-called optical influence functions. The optical influence function for each DoF is found by observing the change in a(t) when an aligned system, at C(t) = [0 5×1 ], has a single DoF increasingly misaligned.…”

Section: State Observer Developmentmentioning

confidence: 99%

See 1 more Smart Citation

Zernike based wavefront alignment in a deployable optic control test bed

Zhang,

Trinh,

Sauer

et al. 2023

Optical Modeling and Performance Predictions XIII

View full text Add to dashboard Cite

An automated optical alignment method is necessary for the efficient operation of deployable optic-equipped earth observation micro-satellites. Implementation of a linear output feedback controller for the alignment of an active optic is investigated on the Control Test Bed (CTB). The output feedback controller calculates the required positional adjustments of the optic using a multi-variable output measurement. The CTB is a refractive optical system by which the wavefront of an incoming collimated beam is modified by control inputs that adjust the position of a lens. The position of this lens can be translated in the x, y, and z axes (despace and defocus) and rotated about the x and y axes (tip and tilt). In the CTB, a Shack-Hartmann wavefront sensor (SHWFS) measures the output as Zernike coefficients. This setup is intended to emulate the necessary adjustments in a simple deployable optic. We describe the process of developing the output feedback controller that can align the CTB as well as discuss the implications of the scheme to a space-based deployable optic telescope. The aberrations induced by misalignment of the active lens were characterized experimentally by disturbing the system along each degree of freedom about the optically aligned point. The experimental results derive a state observer that can sufficiently estimate the misalignment of the lens from a set of relevant Zernike coefficients. Iterative correction of the estimated misalignment in a closed-loop allowed consistent convergence of the CTB to a nearly flat wavefront.

show abstract

Section: Shack-hartmann Wavefront Sensormentioning

confidence: 99%

Section: State Observer Developmentmentioning

confidence: 99%

Zernike based wavefront alignment in a deployable optic control test bed

Zhang,

Trinh,

Sauer

et al. 2023

Optical Modeling and Performance Predictions XIII

View full text Add to dashboard Cite

show abstract

“…This prediction can aid in the implementation of assembly/computer-aided precision alignment, iterative alignment control, and/or the streamlining of manual assembly procedures. Consequently, the realization of a multi remote sensing satellite constellation for simultaneous Earth observations within a single launch window can be accomplished with reduced effort 8, 9 .…”

Section: Introductionmentioning

confidence: 99%

Optimizing design decision-making for remote sensing instrument specification via tolerance sensitivity analysis of Ritchey–Chrétien telescope

Lin

2023

UV/Optical/IR Space Telescopes and Instruments: Innovative Technologies and Concepts XI

View full text Add to dashboard Cite

The objective of this study was to assess the tolerance sensitivity of various aperture sizes in the Ritchey-Chrétien telescope employed in remote sensing instruments. A comparative analysis was performed to identify the optimal system specification considering different aperture sizes and marginal tolerances. The results were then utilized in the Formosat-8 satellite program to determine the most suitable aperture size for fabricating the mirror components and establish the tolerances budget for the system alignment of the Formosat-8 satellite remote sensing instrument.

show abstract

“…Most research has focused on the angular rotation speed. Angular speed measurement is urgently required in control applications and turbo machines [21][22][23][24][25][26][27][28][29][30]. In this letter, we proposed a pitch and yaw angular speed measurement based on line scan vision.…”

Section: Introductionmentioning

confidence: 99%

Pitch and yaw angular speed measurement using Kalman data fusion

Wang

2022

IEICE Electron. Express

View full text Add to dashboard Cite

Pitch and yaw angular speed measurements are vitally important parameters for monitoring the condition of precision machines. In this letter, we propose a dynamic pitch and yaw angular speed measurement system based on line scan vision. The characteristic line scan image can be considered a discrete time sequence, and each column of pixels represents a different time. A double light-spot centroid and double Gaussian fitting algorithm are developed to obtain the centroid coordinates. Kalman data fusion is employed to enhance the accuracy of the obtained measurement results. The experimental results prove that the proposed method is effective and highly accuracy.

show abstract

High precision automated alignment procedure for two-mirror telescopes

Cited by 13 publications

References 19 publications

Zernike based wavefront alignment in a deployable optic control test bed

Zernike based wavefront alignment in a deployable optic control test bed

Optimizing design decision-making for remote sensing instrument specification via tolerance sensitivity analysis of Ritchey–Chrétien telescope

Pitch and yaw angular speed measurement using Kalman data fusion

Contact Info

Product

Resources

About