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.
คณะสถาปัตยกรรม ศิลปะและการออกแบบ
The thesis artwork titled “The Red Mist” presents a narrative adapted from a short story of the same name by Assistant Professor Chatnarong Wisutkul in 2003. The story is set in a future world where people's greed and selfishness have led to a war, forcing them to rely on "breathing machines" to survive in the "red toxic mist." Phakin, a 15-year-old boy, embarks on a journey with a group of refugees. As they pass through abandoned cities, they encounter a boy without a breathing machine who has recently lost his father. Phakin decides to help him, despite objections from others. The boy tries to end his life by shutting off his breathing machine, and when Phakin intervenes to save him, he collapses from inhaling the toxic air. Witnessing Phakin's selfless act, the others are moved and join forces to save both of them. Phakin demonstrates that in difficult times, humans must cooperate and help each other rather than being divided and selfish.
คณะวิศวกรรมศาสตร์
This project aims to introduce an Automated Vertical Metal Sheet Storage System. The project is aimed at teaching how to make an Automation Vertical Metal Sheet Storage System with the integration of microcontroller devices. The project is divided into two main sections, which are the structure and control systems of the Automation Vertical Metal Sheet Storage System that will be designed and drawn through a computer program and constructed using major aluminum structures upon completion of their actual sizes outlined in the programs. Also, a Microcontroller control system using GX Works 2 program from Mitsubishi PLC has been designed for this purpose where it controls up and down movements as well as sideways movement of the pallet. It also has a weighing capability along with touch screen display for displaying information about the steel plates and controlling the Automation Vertical Metal Sheet Storage System with safety light curtain that protect users safety. These tests have shown that the machine operates normally. There are few mistakes whose rates fall within those expected by humans.
คณะเทคโนโลยีสารสนเทศ
Currently, the issue of developmental writing disabilities in children is a matter of great importance for school-age children. Diagnosing whether a child has developmental writing disabilities relies on writing skill assessments, which are administered to those seeking diagnosis and evaluated by medical professionals or experts. However, there are still limitations in the diagnostic process, which depends heavily on expert physicians, leading to a high demand for human resources. To address this, we have developed a method for scoring writing skill assessments using image processing technology, based on existing scoring criteria. Currently, three criteria are used for scoring: writing position, article format, and copying speed. We have also created a web application to make the system more accessible and easier to use.