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FOV splicing optical remote sensing instruments have a strict requirement for the focal length consistency of the lens. In conventional optical-mechanical structure design, each optical element is equally distributed with high accuracy and everyone must have a high machining and assembly accuracy. For optical remote sensors with a large number of optical elements, this design brings great difficulties to lens manufacture and alignment.

Taking the relay lens in an optical remote sensing instrument with the field of view splicing as an example, errors of the system are redistributed to optical elements. Two optical elements, which have the greatest influence on modulation transfer function (MTF) of the system are mounted with high accuracy centering and the other elements are fixed by gland ring with common machining accuracy. The reduction ratio consistency difference among lenses is compensated by adjusting the optical spacing between the two elements.

Based on optical system simulation analysis, the optimized structure can compensate for the difference of reduction ratio among lens by grinding the washer thickness in the range of ±0.37 mm. The test data for the image quality of the lens show that the MTF value declined 0.043 within ±0.4 mm of space change between two barrels. The results indicate that the reduction ratio can be corrected by adjusting the washer thickness and the image quality will not obviously decline.

This paper confirms that this work is original and has not been published elsewhere nor is it currently under consideration for publication elsewhere. In this paper, the optimum structural design of the reduction relay lens for the field of view stitching applications is reported. The method of adjusting washer thickness is applied to compensate for the reduction ratio consistency difference of lenses. The optimized structure also greatly reduces the difficulty of lenses manufacture, alignment and improves the efficiency of assembly.

The movie substitutes such as home cinema, video on demand (VOD), and plasma televisions leaded to a declining attendance of patrons to movie theatres, which urged the invention of IMAX theatre to call movie lovers back to cinemas. Many cinemas plan to renovate their regular digital theatre auditoriums into IMAX theatre auditoriums, but there lack of study for built environmental variations between regular and IMAX theatres. Through the combination of a questionnaire survey and a case study on a leading cinema company in Malaysia, the Tanjong Golden Village Cinemas (TGV), this paper aims to identify the structural and architectural differences between regular digital theatre auditorium and IMAX theatre auditorium in the perspectives of acoustic and visual experiences. The most significant factor influencing the satisfaction of visualization in IMAX is “immersive of picture” followed by “sharpness of colour” and “feels as part of the picture”. The most significant indicators for audio experience in IMAX is “direction of object”, which enable an audience to trace the direction and position of an object on the screen without looking at it. The built environmental variations between regular and IMAX theatres in terms of screen, camera and projection methods, seating, architectural layout, wall design, and sound system arrangement were thoroughly compared in the case study.

Sensor Review publishes the results of a major sensor survey.

The purpose of this paper is to describe how the authors designed a small satellite formation ground test bed in order to study the small satellite formation flying technologies, such as autonomous formation control and network communication. As one of the subsystems, the vision detection system is responsible for the pose (position and orientation) detection of the three small satellite simulators, each of which is composed of a wheeled mobile robot and an on‐board micro control unit. In this paper, the rapid vision locating of the three small satellite simulators in the wide field is discussed.

The scene size required by the test bed has exceeded the scope of one camera, thus how to obtain the complete scene becomes a difficulty. On the base of image mosaic, a vision system composed of two cameras is designed to capture the scene simultaneously. After the two overlapped images are rapidly stitched, the real‐time view of the big scene is attained. Second, the new color tag representing the pose of small satellite simulators is designed, which can be easily identified.

A real‐time multiple mobile robots visual locating system is introduced, in which the global search algorithm and track search algorithm are combined together to identify the real‐time pose of multiple mobile robots. The switching strategy between the two algorithms is given to ensure the accuracy and improve retrieval speed.

The paper shows how, without camera calibration, the pose of each small satellite simulator in the world coordinate system can be directly calculated by the coordinate transformation from the image coordinate system to the world coordinate system based on relative measurement. The accuracy and real‐time performance of the vision detection system have been validated by experiments on locating static tags and dynamic tracking three small satellite simulators.

THE Farnborough 1966 Show was at first glance much the same mixture as before, but the second glance was the more revealing. The participation in the flying display of European aircraft by no means swamped the air, even if the Italian verve took the acrobatic honours, but the theme of collaboration with other countries was to be found on practically every stand inside the exhibition tent. It was obvious that the smaller firms not directly involved in production agreements with other nations were very export conscious. The pacemaker of all this collaboration was of course the Concorde, only to be seen in model form, but rapidly taking shape at Toulouse and Filton, and many of the equipment manufacturers had Concorde hardware on display. Beagle announced the Pup, Britten‐Norman produced the production Islander, and Handley Page showed the Jetstream mock‐up. After many years of neglect, the industry is now taking an interest in the general aviation market. The P.1127 (R.A.F.) made its first appearance. The paradox of the P.1127 is that it is almost a part of Farnborough history, yet there is no other V/S.T.O.L. aircraft in the world that has but a fraction of the operating experience it has gained. Farnborough this year gave the impression of being more a serious trade show, and less a public spectacle. Sir Richard Smeeton, Director of the Society of British Aerospace Companies, reported that the exhibiting firms had received more serious business enquiries this year than ever before, and he forecast that 1968 would be a vintage year, which would see the appearance of the HS.801, the Concorde and Jaguar in the Farnborough skies. It is not possible to cover every exhibit shown at the Farnborough Show, but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

This paper aims to review the use of imaging technologies in robotics, with an emphasis on inspection applications and the control of autonomous robots.

Following a brief introduction, this paper first considers vision‐based robotic inspection systems and highlights a selection of recent applications. Second, it considers the use of vision in autonomous robot navigation and discusses some of the challenges and recent developments.

This shows that developments in machine vision have led to vision systems being used in a diversity of component‐level and in‐service robotic inspection tasks. It also illustrates that vision systems have a key role to play in the emerging generation of autonomous, mobile robots.

This paper provides a review of recent developments in vision‐based robotic inspection and autonomous, mobile robot navigation.

An examination of the advantages of fail safe design and present non‐destructive testing techniques, and the importance of facilitating inspection at the design stage. THE introduction to this paper justifies in depth the case for fail safe philosophies in aircraft structural design. The advantages include improved safety, weight savings, the full availability of the potential fatigue life of each individual aircraft in the fleet, protection against accidental damage in service and manufacturing errors, together with a good resale value.

Fire smoke detection in petrochemical plant can prevent fire and ensure production safety and life safety. The purpose of this paper is to solve the problem of missed detection and false detection in flame smoke detection under complex factory background.

This paper presents a flame smoke detection algorithm based on YOLOv5. The target regression loss function (CIoU) is used to improve the missed detection and false detection in target detection and improve the model detection performance. The improved activation function avoids gradient disappearance to maintain high real-time performance of the algorithm. Data enhancement technology is used to enhance the ability of the network to extract features and improve the accuracy of the model for small target detection.

Based on the actual situation of flame smoke, the loss function and activation function of YOLOv5 model are improved. Based on the improved YOLOv5 model, a flame smoke detection algorithm with generalization performance is established. The improved model is compared with SSD and YOLOv4-tiny. The accuracy of the improved YOLOv5 model can reach 99.5%, which achieves a more accurate detection effect on flame smoke. The improved network model is superior to the existing methods in running time and accuracy.

Aiming at the actual particularity of flame smoke detection, an improved flame smoke detection network model based on YOLOv5 is established. The purpose of optimizing the model is achieved by improving the loss function, and the activation function with stronger nonlinear ability is combined to avoid over-fitting of the network. This method is helpful to improve the problems of missed detection and false detection in flame smoke detection and can be further extended to pedestrian target detection and vehicle running recognition.