The capture of a target spacecraft by a chaser is an on-orbit docking operation that requires an accurate, reliable, and robust object recognition algorithm. Vision-based guided spacecraft relative motion during close-proximity maneuvers has been consecutively applied using dynamic modeling as a spacecraft on-orbit service system. This research constructs a vision-based pose estimation model that performs image processing via a deep convolutional neural network. The pose estimation model was constructed by repurposing a modified pretrained GoogLeNet model with the available Unreal Engine 4 rendered dataset of the Soyuz spacecraft. In the implementation, the convolutional neural network learns from the data samples to create correlations between the images and the spacecraft’s six degrees-of-freedom parameters. The experiment has compared an exponential-based loss function and a weighted Euclidean-based loss function. Using the weighted Euclidean-based loss function, the implemented pose estimation model achieved moderately high performance with a position accuracy of 92.53 percent and an error of 1.2 m. The in-attitude prediction accuracy can reach 87.93 percent, and the errors in the three Euler angles do not exceed 7.6 degrees. This research can contribute to spacecraft detection and tracking problems. Although the finished vision-based model is specific to the environment of synthetic dataset, the model could be trained further to address actual docking operations in the future.
In one, docking is defined as “when one incoming spacecraft rendezvous with another spacecraft and flies a controlled collision trajectory in such a manner to align and mesh the interface mechanisms”, and defined docking as an on-orbital service to connect two free-flying man-made space objects. The service should be supported by an accurate, reliable, and robust positioning and orientation (pose) estimation system. Therefore, pose estimation is an essential process in an on-orbit spacecraft docking operation. The position estimation can be obtained by the most well-known cooperative measurement, a Global Positioning System (GPS), while the spacecraft attitude can be measured by an installed Inertial Measurement Unit (IMU). However, these methods are not applicable to non-cooperative targets. Many studies and missions have been performed by focusing on mutually cooperative satellites. However, the demand for non-cooperative satellites may increase in the future. Therefore, determining the attitude of non-cooperative spacecrafts is a challenging technological research problem that can improve spacecraft docking operations. One traditional method, which is based on spacecraft control principles, is to estimate the position and attitude of a spacecraft using the equations of motion, which are a function of time. However, the prediction using a spacecraft equation of motion needs support from the sensor fusion to achieve the highest accuracy of the state estimation algorithm. For non-cooperative spacecraft, a vision-based pose estimator is currently developing for space application with a faster and more powerful computational resource.
คณะอุตสาหกรรมอาหาร
This study aims to investigate the co-fermentation process between lactic acid bacteria (LAB) and Saccharomyces cerevisiae in the production of sour beer, with a focus on its impact on product quality, including pH, organic acid content, sugar content, and sensory characteristics. In this experiment, selected LAB strains and S. cerevisiae were utilized under controlled fermentation conditions. The microbial ratio was optimized to enhance growth and the production of key compounds. The findings indicate that co-fermentation significantly reduces pH compared to fermentation with yeast alone. Furthermore, an increase in lactic acid was observed due to sugar consumption by LAB, contributing to the distinctive flavor profile of sour beer.
วิทยาลัยนวัตกรรมการผลิตขั้นสูง
The offline evaluation system for Thai-language large language models (LLMs) is designed to enable experts to efficiently test and assess various LLMs without relying on external services. This enhances the flexibility in selecting LLMs that best suit organizational needs or expert systems (ES). The system operates on personal computers, ensuring data security by eliminating concerns about external data storage. Additionally, it supports model testing and development using Retrieval-Augmented Generation (RAG), allowing access to domain-specific knowledge for accurate, energy-efficient processing. This ensures that the models can perform optimally and effectively meet the demands of organizations and expert systems.
คณะอุตสาหกรรมอาหาร
This research aims to develop plant-based Thai traditional sausage(Sai oua) using young jackfruit as the main raw material. To be an alternative to replace meat by studying the development of formula, changes in physical and physical chemistry during the preservation of the product, young jackfruit has dominant properties of meat-like fibres and can absorb the smell and taste of spices well. The results of the study found that young jackfruit that have been boiled at 100 degrees Celsius for 30 minutes have the fibre closest to cooked chicken. In addition, the study of changes during storage at different temperatures found that the colour and Water Activity (Aw) have changed slightly. While the pH value (pH) decreased and the value of Thiobarbituric Acid Reactive Substances (T-BARS) increased. In terms of texture, it was found that the toughness increased and the elasticity decreased. Compared to the control formula, this study suggests that young jackfruit is a suitable raw material for the production of fillings from plants.