The motions of three bodies like Sun-Asteroid-Jupiter system or triple star system are formalized as hierarchical three body problem. When the third body orbits around the rest in a highly inclined elliptic orbit, the system undergoes the oscillation, called the Kozai oscillation, where the eccentricity may increase with decrease of the inclination of the orbital plane. This type of orbits often ends in disruption of the system, that is, the outermost body is thrown away. Inspections of such orbits show that they undergo many state transitions, each of which visually seems to form an invariant curve of the Kozai oscillation. However, the transition process has not been well understood. For this reason, we try to map these trajectories into a secular perturbation model with data assimilation technique. Via such mapping, we will demonstrate to extract the state transitions (between libration and circulation as well as between different levels of the circulation.

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There is a growing demand for automation by robots in the home replacement meal industry due to labor shortages in food factories and from the perspective of the SDGs[1]. In this research, we are developing autonomous work robots that can perform home replacement meal tasks and developing the technology for industrial food automation using Artificial Intelligence (AI) to improve productivity, security, and safety. In this paper, we perform weight estimation of the served object to identify the amount of spaghetti grasped by the robot. We created our dataset of spaghetti used for weight estimation. Spaghetti of varying weight is in different types of containers, placed at random positions in the robot workspace. The proposed model is shown to estimate the weight of spaghetti with an error of at most 10%.

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Inspired by ants and fishes in nature, the multi-agent system plays a huge role in production and manufacturing in modern society. This paper takes UGV as the object and designs a multi-UGV test platform. The platform composes of UGVs, ultra-wideband, and Bluetooth Mesh. At the same time, the UGV can achieve different control objectives by changing the code of main controller. The formation control protocol of UGVs is designed and its stability is analyzed. The effectiveness of the protocol is verified by numerical simulation. Finally, the designed control protocol is applied to the designed hardware simulation platform to verify the effectiveness of the simulation platform.

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This paper systematically summarizes the current research status and development of obstacle avoidance algorithms. The characteristics of the unmanned vehicle obstacle avoidance algorithms are classified into traditional and intelligent algorithms. Based on the above classification, the representative research results in recent years are introduced, focusing on the advantages and disadvantages of various types of obstacle avoidance algorithms. The future development trend of the unmanned vehicle obstacle avoidance algorithm is also prospected in order to provide some ideas for the subsequent research.

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I proposed a discrete mathematical SEPIR model for seasonal influenza. In this study, by examining affection by pre-infectious students in real data, I found that the first patients were discovered four days after the consecutive holidays, namely the incubation period passing at our academy. I show that students are likely to super-spread seasonal influenza by the day the first patients are discovered. Then, it is effective to strengthen for seasonal influenza measures within the community especially four days after the consecutive holidays.

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This study examines the key success factors of ERP introduction in Taiwan’s manufacturing industry as a reference for enterprises to reduce the high and unforeseeable financial and time costs of ERP introduction. In the second phase, a questionnaire study was conducted using the Analytic Hierarchy Process to extract the relative weights of the distance between primary and secondary dimensions, and 5 primary dimensions were derived, including Management/Organization”, “Introduction Process”, “Technical Support”, “Documentation”, and “Personnel”, as well as 15 secondary dimensions.

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In recent years, autonomous platforms have been developed to reduce the cost of various activities in the field of marine engineering, such as ocean observation platforms, autopilot vessels for maintenance of offshore wind farms, and the installation of submarine drilling rigs. Catamaran-type USVs are one of the useful platforms in these activities. The authors have been developing an experimental testbed of USV platform to conduct basic studies on control algorithms through sea experiments. The USV must be capable of following a given trajectory and accomplishing its mission in the face of wind, currents, and other unknown disturbances while avoiding other vessels and obstacles at sea. This paper presents our testbed design and LQR based control algorithm to implement the basic ability of trajectory tracking, which is intended to be used to collect data for designing AI based control algorithm in the near future.

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Human experts have assured social infrastructure inspections, and recently an automated inspection is expected as an integrated system of the flight vehicle with software algorithms of the image processing. For the submillimeter-width concrete-crack detection, we have introduced Morphological Component Analysis (MCA) to be able to find those positions. Conventional image processing methods work well for thick-width crack detections, while the thin-width crack detection is highly difficult. We successfully demonstrated a concrete crack detection from images through proximity cameras in a specialized multi-copter and MCA-based crack position estimations and the linear regression-based sub-pixel width estimation were integrated together. It will open a new door to engineering in the actual field work, which can be widely applicable for social infrastructure inspections in general.

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One of the major concerns in rural area is the struggle to get clean drinking water. This is because they are not supplied with clean water and thus must source for water from rivers, rainwater, and wells which are often contaminated and unsafe for drinking. The objective of this study is to design and fabricate a functional prototype of a pedal powered water purifier, and to ensure that purified water is safe for consumption based on chemical water analysis. A structural analysis via Finite Element Analysis (FEA) simulation is performed on the prototype. Then, the quality of the purified water is compared to the Drinking Water Guidelines (DWG) provided by the World Health Organization (WHO). The system utilizes the distillation method to produce clean drinking water. The charging efficiency of the generator has reached 48.74% at 60rpm cadence. The outcome from FEA results showed that the structure of the supporting frame can withstand up to three times the normal load. In addition, based on the chemical analysis of purified water, it has been proven that it meets the standards set by WHO and is safe for consumption.

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Fatigue damage is the main form of spring failure, the spring fatigue test is a mandatory test item before the spring is put into use. Especially for springs in key parts such as automobile suspension springs, train damping springs and engine valves, they can only be put into use after passing strict tests. Since there are many different types of spring structures with different stresses, the fatigue detection and evaluation methods are also different. This paper designs the compression spring fatigue tester from several aspects, including composition structure, working principle, and technical points. This spring tester can test the maximum number of cycles of a spring for a given failure condition by applying a cyclic variable load to the spring.

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