Bionic Compound Eye Research Articles

Fabrication of liquid-filled zoom compound eyes with a tunable focal length

The conventional bionic compound eye system encounters challenges associated with a complex zoom structure, susceptibility to wear, and elevated costs. In this paper, a preparation method of liquid-filled zoom compound eyes is proposed. A polydimethylsiloxane (PDMS) film is integrated with a microfluidic chamber composed of polymethyl methacrylate (PMMA). The microlens array (MLA, hexagonal array, diameter 800 µm, center distance 850 µm) on the PDMS film is prepared by a wettability-guided dipping method. The sub-eye focal length on zoom compound eyes (ZCEs) is 1.42 mm. By controlling the volume of deionized (DI) water injected into the chamber from 2.41 to 2.71cm3, the focal length of the main lens is adjusted from infinity to 55.51 mm, and the FOV is adjusted from 32° to 58°. This large aperture ZCE combines the advantages of monocular and compound eyes. This method has great potential for advanced micro-optical devices with a wide field of view and tunable imaging capabilities.

Research on key technology of cooled infrared bionic compound eye camera based on small lens array

Traditional 2D imaging technologies are limited by the need for a large field of view and their sensitivity to small target motion. Inspired by the characteristics of insect compound eye structure, we propose an infrared bionic compound eye camera based on a small lens array. The camera is composed of 61 small lens arrays mounted on a curved spherical shell and a relay optical system. The imaging device is a high-performance cooled mid-wave infrared detector. This is an innovative design for an infrared biomimetic compound eye camera system that provides a wide field of view and all-day detection capability. Aimed to meet the specified requirements. The optical system achieves a 100% cold-membrane match between the infrared optical system and the cooled detector, and the relay optical system optimizes the large-field aberration by introducing a higher-order aspheric surface and modifying the geometric surface of the lenses. Our entire system enables an observation field angle of 108∘×108∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$108^\\circ \ imes 108^\\circ$$\\end{document}. The experiments showed that the image quality of the system is high, each ommatidium was effective within the imaging range of the compound eye camera, resulting in an improved signal-to-noise ratio in various scenes.

Bio-inspired foveal super-resolution method for multi-focal-length images based on local gradient constraints

Most existing super-resolution (SR) imaging systems, inspired by the bionic compound eye, utilize image registration and reconstruction algorithms to overcome the angular resolution limitations of individual imaging systems. This article introduces a multi-aperture multi-focal-length imaging system and a multi-focal-length image super-resolution algorithm, mimicking the foveal imaging of the human eye. Experimental results demonstrate that with the proposed imaging system and an SR imaging algorithm inspired by the human visual system, the proposed method can enhance the spatial resolution of the foveal region by up to 4 × compared to the original acquired image. These findings validate the effectiveness of the proposed imaging system and computational imaging algorithm in enhancing image texture and spatial resolution.

Femtosecond Laser Microfabrication of Artificial Compound Eyes

Over millions of years of evolution, arthropods have intricately developed and fine-tuned their highly sophisticated compound eye visual systems, serving as a valuable source of inspiration for human emulation and tracking. Femtosecond laser processing technology has attracted attention for its excellent precision, programmable design capabilities, and advanced three-dimensional processing characteristics, especially in the production of artificial bionic compound eye structures, showing unparalleled advantages. This comprehensive review initiates with a succinct introduction to the operational principles of biological compound eyes, providing essential context for the design of biomimetic counterparts. It subsequently offers a concise overview of crucial manufacturing methods for biomimetic compound eye structures. In addition, the application of femtosecond laser technology in the production of biomimetic compound eyes is also briefly introduced. The review concludes by highlighting the current challenges and presenting a forward-looking perspective on the future of this evolving field.

Velocity measurement technology of curved bionic compound eye

Velocity measurement technology of curved bionic compound eye

Bionic Compound Eye Based on a Flexible Fresnel Lens Array

Bionic Compound Eye Based on a Flexible Fresnel Lens Array

Double-Glued Multi-Focal Bionic Compound Eye Camera.

Compound eye cameras are a vital component of bionics. Compound eye lenses are currently used in light field cameras, monitoring imaging, medical endoscopes, and other fields. However, the resolution of the compound eye lens is still low at the moment, which has an impact on the application scene. Photolithography and negative pressure molding were used to create a double-glued multi-focal bionic compound eye camera in this study. The compound eye camera has 83 microlenses, with ommatidium diameters ranging from 400 μm to 660 μm, and a 92.3 degree field-of-view angle. The double-gluing structure significantly improves the optical performance of the compound eye lens, and the spatial resolution of the ommatidium is 57.00 lp mm-1. Additionally, the measurement of speed is investigated. This double-glue compound eye camera has numerous potential applications in the military, machine vision, and other fields.

Optimal vector matching fusion method for bionic compound eye polarization compass and inertial sensor integration

The compound eyes of insects can extract the heading by sensing multi-directional polarization information. Inspired by this, the integration with bionic eye polarization compass and low-precision MEMS inertial sensors yields a new choice for autonomous navigation in a GPS-denied environment. However, the occlusion environments, such as jungles and buildings, seriously affects the attitude estimation accuracy by destroying the polarization information. Considering the above problem, this paper proposes a reliable attitude estimation method based on vector matching measurement models for integration with bionic compound eye polarization compass and low-cost MEMS inertial sensors, including the polarization vector, solar vector, and gravity vector. To realize the matching and fusion among these vector models, the vector optimization selection algorithm is designed according to the number of visible polarization sensors in the occlusion environment. Particularly, the vector optimization selection factor is designed according to the error between the measured and theoretical polarization vectors. Furthermore, when using the solar vector estimation model, the degree of the polarization is applied to improve the calculation accuracy of the solar vector. The gravity vector measurement model is employed to enhance the autonomy of the integration. Finally, the effectiveness of the proposed method is verified by simulated and outdoor experiments under tree obscuration.

The Application of Artificial Compound Eye in Precision Guided Munitions for Urban Combat

As an ideal visual perception system with miniaturization, multi-aperture, wide field of view, low aberration, infinite depth of field, high efficiency and real-time, bionic compound eye has obvious intelligent characteristics, which provides a new idea for the future intelligent development of precision guided weapons, and has also been highly concerned by the US military. Under the leadership of the military, the United States has carried out a series of studies and achieved a series of results. The strategic position of urban combat in the future is analyzed. The requirements of the U.S. Air Force for the next generation of precision-guided munitions, and also the strategic significance of developing urban combat weapons and equipment is described. The advantages and characteristics of artificial compound eye are briefly described. Mainly discussed a series of WFOV artificial compound eye seeker being studied and developed by the U.S. Air Force for urban warfare, as well as the research and development process. Finally, the development suggestion of the WFOV artificial compound eye seeker is given.

Wide field of view and full Stokes polarization imaging using metasurfaces inspired by the stomatopod eye

Abstract Wide field of view and polarization imaging capabilities are crucial for implementation of advanced imaging devices. However, there are still great challenges in the integration of such optical systems. Here, we report a bionic compound eye metasurface that can realize full Stokes polarization imaging in a wide field of view. The bionic compound eye metasurface consists of a bifocal metalens array in which every three bifocal metalenses form a subeye. The phase of the bifocal metalens is composed of gradient phase and hyperbolic phase. Numerical simulations show that the bifocal metalens can not only improve the focusing efficiency in the oblique light but also correct the aberration caused by the oblique incident light. And the field of view of the bionic compound eye metasurface can reach 120° × 120°. We fabricated a bionic compound eye metasurface which consists of three subeyes. Experiments show that the bionic compound eye metasurface can perform near diffraction-limited polarization focusing and imaging in a large field of view. The design method is generic and can be used to design metasurfaces with different materials and wavelengths. It has great potential in the field of robot polarization vision and polarization detection.

Polarization Orientation Method Based on Remote Sensing Image in Cloudy Weather

Autonomous navigation technology is a core technology for intelligent operation, allowing the vehicles to perform tasks without relying on external information, which effectively improves the concealability and reliability. In this paper, based on the previous research on the bionic compound eye, a multi-channel camera array with different polarization degrees was used to construct the atmospheric polarization state measurement platform. A polarization trough threshold segmentation algorithm was applied to study the distribution characteristics and characterization methods of polarization states in atmospheric remote sensing images. In the extracted polarization feature map, the tilting suggestion box was obtained based on the multi-direction window extraction network (similarity-based region proposal networks, SRPN) and the rotation of the suggestion box (Rotation Region of interests, RRoIs). Fast Region Convolutional Neural Networks (RCNN) was used to screen the suggestion boxes, and the Non-maximum suppression (NMS) method was used to select the angle, corresponding to the label of the suggestion box with the highest score, as the solar meridian azimuth in the vehicle coordinate system. The azimuth angle of the solar meridian in the atmospheric coordinate system can be calculated by the astronomical formula. Finally, the final heading angle can be obtained according to the conversion relationship between the coordinate systems. By fitting the measured data based on the least Square method, the slope K value is −1.062, RMSE (Root Mean Square Error) is 6.984, and the determination coefficient R-Square is 0.9968. Experimental results prove the effectiveness of the proposed algorithm, and this study can construct an autonomous navigation algorithm with high concealment and precision, providing a new research idea for the research of autonomous navigation technology.

Development of neural‐network‐based stereo bionic compound eyes with fiber bundles

SummaryThe compound eye system has many unique advantages, enabling organisms to quickly and accurately obtain the three‐dimensional spatial information of the target. Therefore, its bionic applications have great potential in object localization, dynamic tracking, and 3D reconstruction. However, the current bionic compound eye systems still have great difficulties in target detection. Most of the bionic compound eye systems only verify the possibility of three‐dimensional (3D) detection, and there is no suitable calibration and detection scheme. In this article, a fiber‐optic stereo bionic compound eye is designed, and a simple and rapid calibration method suitable for this system is selected by comparing two effective optical information. Further, the system quantitatively analyzes the detection performance of the target to achieve precise positioning and dynamic trajectory tracking. In the static detection experiment, the average detection errors of the 3D position at the horizontal angle, the elevation angle and the depth are 0.33°, 0.32° and 1.84 mm, respectively. In the dynamic trajectory tracking experiment, the circle radius errors in the X‐Z plane and Y‐Z plane are 0.04 and 2.20 mm, respectively. The proposed system provides a new perspective to understand the nature of the compound eye.

Fabrication of a bionic compound eye on a curved surface by using a self-assembly technique.

Microlens arrays on curved surfaces are regarded as critical elements of bionic compound eyes (BCEs), which exhibit the comparative advantages of a wide field of view and tracking fast-moving objects. However, the fabrication of a curved microlens array is still challenging. Along these lines, in this work, a straightforward, rapid, and low-cost technique for the fabrication of curved microlens arrays is reported by using the self-assembly technique. A reactive ion etching process treated the surface of the curved polydimethylsiloxane (PDMS) substrate to generate a hydrophobic-hydrophilic pattern. Then, the curved microlens array can be realized by dewetting a liquid glue onto the substrate using the dip-coating method and followed by crosslinking. The proposed BCE structure consists of 2400 microlenses (400 - µm diameter and 440 - µm center distance) arranged in a hexagonal configuration on a curved PDMS surface (34 - mm diameter and 40.4 - mm curvature radius). A field-of-view of 50° was demonstrated, which has potential applications in various fields including imaging sensors, medical diagnostics, machine vision systems, and photodetectors.

Three-Dimensional Reconstruction Method for Bionic Compound-Eye System Based on MVSNet Network

In practical scenarios, when shooting conditions are limited, high efficiency of image shooting and success rate of 3D reconstruction are required. To achieve the application of bionic compound eyes in small portable devices for 3D reconstruction, auto-navigation, and obstacle avoidance, a deep learning method of 3D reconstruction using a bionic compound-eye system with partial-overlap fields was studied. We used the system to capture images of the target scene, then restored the camera parameter matrix by solving the PnP problem. Considering the unique characteristics of the system, we designed a neural network based on the MVSNet network structure, named CES-MVSNet. We fed the captured image and camera parameters to the trained deep neural network, which can generate 3D reconstruction results with good integrity and precision. We used the traditional multi-view geometric method and neural networks for 3D reconstruction, and the difference between the effects of the two methods was analyzed. The efficiency and reliability of using the bionic compound-eye system for 3D reconstruction are proved.

Recognition and Detection of Wide Field Bionic Compound Eye Target Based on Cloud Service Network.

In this paper, a multidisciplinary cross-fusion of bionics, robotics, computer vision, and cloud service networks was used as a research platform to study wide-field bionic compound eye target recognition and detection from multiple perspectives. The current research status of wide-field bionic compound-eye target recognition and detection was analyzed, and improvement directions were proposed. The surface microlens array arrangement was designed, and the spaced surface bionic compound eye design principle cloud service network model was established for the adopted spaced-type circumferential hierarchical microlens array arrangement. In order to realize the target localization of the compound eye system, the content of each step of the localization scheme was discussed in detail. The distribution of virtual spherical targets was designed by using the subdivision of the positive icosahedron to ensure the uniformity of the targets. The spot image was pre-processed to achieve spot segmentation. The energy symmetry-based spot center localization algorithm was explored and its localization effect was verified. A suitable spatial interpolation method was selected to establish the mapping relationship between target angle and spot coordinates. An experimental platform of wide-field bionic compound eye target recognition and detection system was acquired. A super-resolution reconstruction algorithm combining pixel rearrangement and an improved iterative inverse projection method was used for image processing. The model was trained and evaluated in terms of detection accuracy, leakage rate, time overhead, and other evaluation indexes, and the test results showed that the cloud service network-based wide-field bionic compound eye target recognition and detection performs well in terms of detection accuracy and leakage rate. Compared with the traditional algorithm, the correct rate of the algorithm was increased by 21.72%. Through the research of this paper, the wide-field bionic compound eye target recognition and detection and cloud service network were organically provide more technical support for the design of wide-field bionic compound eye target recognition and detection system.

Research and development of Wide-Field-of-View bionic compound eye photoelectric imaging detection technology

Research and development of Wide-Field-of-View bionic compound eye photoelectric imaging detection technology

3D Printed Embedded Metamaterials

AbstractThe manufacturing of 3D and conformal metamaterials remains a major challenge. The projection micro‐stereolithography 3D printing technology combined with the liquid metal filling method is employed here to fabricate the metamaterials, which are characterized with embedded features that can effectively protect the metal resonance layer from external influence, and integrated molding of macro–micro structures and function‐structure. To demonstrate the robustness and flexibility of the proposed method, three types of metamaterials are fabricated: 3D orthogonal split‐ring resonator metamaterial, bionic compound eye conformal metamaterial, and a five‐layer broadband conformal metamaterial in the form of hemispherical moth‐eye, which are costly, tedious, and time consuming in conventional fabrication methods. And the layout of the filling channel is optimized and the polydimethylsiloxane coating post‐treatment process is applied to smooth the surface roughness caused by the staircase effect of 3D printing to improve the transmission performance of metamaterial devices. The transmission properties are measured using terahertz time‐domain spectroscopy system and the experimental results show that the method proposed in this paper makes metamaterial manufacture no longer limited to complex structures, which effectively expands the application range of metamaterials.

Design and simulation of bionic compound eye with electrowetting liquid lens

To solve the problem that the bionic compound eye system can't zoom adaptively, a zoomable bionic compound eye system based on electrowetting-on-dielectric liquid lens cambered array is proposed. The influence of the system structure on the imaging performance is analyzed, and the adaptive zoom capability of the system and the moving range of the corresponding image plane are calculated. The results show that the field of view angle increases with the increase of the curvature of the base. Compared with the non-uniform lens array, the uniform lens array can significantly reduce the defocus aberration of the system. Reducing the size of the lens unit can also decrease the defocus aberration of the edge lens. When the object distance or receiver position is changed, the defocus aberration of the system will be reduced by adjusting the focal length of the lens unit. The movable range of the system receiver is 1.9 mm~15 mm.

Analysis and Optimization of Computer Trajectory Based on Compound Eye Vision System

With the rapid development of science and technology, people have higher and higher requirements for target detection technology, which requires us to solve the disadvantages of traditional cameras, such as the difficulty of panoramic photography and continuous tracking motion. However, compound eye insects have a visual system composed of fewer neurons, which can achieve rapid detection and capture of objects of interest. Therefore, based on the principle of compound eye vision, a bionic compound eye panoramic detection system is designed in this paper, which can realize panoramic real-time detection through multiple sub eye cameras. Through the compound eye vision system, we can accurately locate the pan tilt controller, which can provide a comprehensive panoramic motion image. Through the principle of automatic windowing, we can acquire the image of moving area by multi-layer window. Then, through the relevant image processing methods, such as binarization, median filtering, spatial filtering, moving object detection, edge detection and other methods, we can get a relatively clear moving object contour and trajectory analysis, which can achieve full field of view, high sensitivity detection and tracking.

Bionic Compound Eye-Inspired High Spatial and Sensitive Tactile Sensor

Haptics plays an important role in grasping and manipulating objects for human hands and artificial robotic hands. The density of tactile receptors at the tips of the fingers is very high, reaching 140 units/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . However, the density of the existing tactile sensors is very low. To increase the density of the 3-D tactile sensor, a novel high-density arrayed and curved 3-D tactile sensor based on bionic compound eye with the density up to 42 units/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> is proposed in this article. The tactile sensor can detect both normal force and shear force since it is isotropic. The force measurement setup has been successfully built with a sensitivity of 0.000280 mN/Gray for normal force and 0.0262 N/ μm for shear force. The sensor will provide a technical basis for force measurement of surgical robots and manipulators.