MAVHUNDU, C. Konstelace výukových mikrosatelitů formátu CubeSat [online]. Brno: Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií. 2025.
The aim of this thesis is to develop a simplified educational CubeSat constellation with UHF-band communication using the AX.25 protocol. The student took a modular approach in solving the thesis, emphasising the use of commercial off-the-shelf (COTS) components and striving for compatibility with existing educational satellites in the department STEM laboratory. The effort invested in the mechanical design and the inclusion of finite element analysis (FEA) for structural and thermal evaluation are appreciated. This demonstrates a good understanding of the basic mechanical considerations involved in developing small satellites. However, the thesis itself does not fulfil all the requirements set out in the assignment. Most critically, the communication subsystem centred on the AX.25 protocol over UHF was not successfully implemented. No working communication link has been demonstrated, and the current firmware only just covers the basics of setup and testing, with key functionality still missing. This is a significant issue as it was one of the work's main goals. While the text includes extensive theoretical background, much of it is too general and repeated across sections, lacking technical depth. The actual constellation is not well described and would benefit from a more detailed design description. While the hardware and software sections document progress, they do not analyse or justify design decisions in sufficient detail. Furthermore, the thesis suffers from occasional formatting inconsistencies, wrong image enumeration and numerous typographical errors, as well as a lack of proper citation formatting (e.g. cit. [19]). The text is difficult to read, and the author often uses long descriptions instead of tables, pictures, or diagrams. The language level of the thesis is average and the text has been submitted for a final check at the very last moment. Regular consultations were conducted throughout the semester. The student was always properly prepared and showed a proactive approach in the prototyping and integration phases of the structural and hardware subsystems. I also appreciated the student's participation in the EEICT student conference, presenting a paper on this topic. However, the planning of the work schedule could have been much better, particularly with regard to the software development. In conclusion, while the student demonstrated motivation and creativity, making valuable progress in mechanical and structural aspects, the lack of a communication system is a significant shortcoming. As it stands, the thesis does not fully demonstrate the expected outcome and cannot be used for educational purposes on the constellation topic without further development. I recommend that the student addresses these shortcomings, especially with regard to the format of the citations, and resubmits the thesis for defence at a later date.
The thesis aims to design a simplified CubeSat constellation for educational use, including working communication over UHF using AX.25 protocol, based on selected COTS components. The document includes a broad theoretical introduction, but much of the content is general and repeated, with limited factual value. The text often lacks clarity, partly due to long descriptions of obvious facts and low-level details that could be better presented in tables or diagrams. This weakens the technical focus and makes the thesis harder to read. The actual constellation design is missing. The work moves directly from general satellite information to a set of selected modules, without analysis of system architecture, or reasons for the chosen setup. The hardware design is very close to an earlier project [36], and almost all parts are pre-assembled commercial modules. While that may be acceptable for a student project, it reduces the originality and complexity of the work. Most importantly, the required radio communication using FSK and AX.25 was not implemented. This is, in my view, the main issue: the key part of the assignment - building and demonstrating a working communication link - is missing. There is no proof of functioning RFM communication, and the firmware included is only a basic structure, suitable for early testing but far from complete. Some subsystems are also not working, such as current sensing. Without implementation and demonstration of communication, the core task remains unfinished. I recommend that the student prepares a basic demonstration of working communication as part of the thesis defense.
eVSKP id 168270