Control theory, once described as the “Physics of the 21st Century,” is pervading to almost all subjects of higher learning. However, it is a difficult topic for many students, especially when introduced at the undergraduate lower level. Providing hands-on experience is often a great aid for teaching difficult concepts, but for control theory forcing a hands-on component can distract from the learning if the students are unprepared. An effective control theory laboratory curriculum builds on the foundations of statics and dynamics, circuit theory, signal processing and programming course-work. However, undergraduate students have a limited educational experience and are typically lacking in one or more of those foundations. Coupled with the unfamiliarity of the common equipment found in teaching labs, students often find themselves overwhelmed and struggle with the setups, limiting their exposure to the topic of control theory. Some industry and education companies have introduced extensive control workstations to bring integrated control theory to a teaching laboratory; however these systems are expensive and specialized, limiting their reach and effectiveness. In this paper, a low-cost mechatronics control theory personal laboratory setup with a proposed curriculum is developed for undergraduate students that addresses their uncertain foundation and improves accessibility by introducing portability to maximize the learning outcomes.

The noise control of a compressor has always been a hot spot in the field of industrial application. In this paper, the air inlet structure of the sound insulation hood of an air compressor unit was studied and improved. Acoustic finite element numerical simulation analysis of the sound insulation hood model was carried out using the acoustic software LMS Virtual Lab Acoustics. The simulation results were compared with the experimental data to verify the correctness of the model, and the theoretical results showed a good agreement with the experiment data. The sound insulation performance of the sound insulation hood under different structures was also investigated in this paper. The results show that the main source of unit noise leakage is outward radiation through the air inlet. In addition, the noise at the air inlet of the unit and the overall noise were significantly reduced compared with the traditional sound insulation hood upon installing 120° and 90° diaphragm structures on the inner wall of the air inlet. The optimization results show that the noise reduction effect of the sound insulation hood with a 90° diaphragm structure was better than that with a 120° diaphragm structure.

Motivated by the growing technology of control and data processing as well as the increasingly complex designs of the new generation of gas turbine engines, a fully automatic control strategy that is capable of dealing with different aspects of operational and safety considerations is required to be implemented on gas turbine engines. An advanced practical control mode satisfaction method for the entire operating envelope of gas turbine engines is proposed in this paper to achieve the optimal transient performance for the engine. A constraint management strategy is developed to generate different controller settings for short-range fighters as well as long-range intercontinental aircraft engines at different operating conditions by utilizing a model predictive control approach. Then, the designed controller is tuned and modified with respect to different realistic considerations including the practicality, physical limitations, system dynamics, and computational efforts. The simulation results from a verified two-spool turbofan engine model and controller show that the proposed method is capable of maneuverability and/or fuel economy optimization indices while satisfying all the predefined constraints successfully. Based on the parameters, natural frequencies, and dynamic behavior of the system, a set of optimized weighting factors for different engine parameters is also proposed to achieve the optimal and safe operation for the engine at different flight conditions. The paper demonstrates the effects of the prediction length and control horizon; adding new constraints on the computational effort and the controller performance are also discussed in detail to confirm the effectiveness and practicality of the proposed approach in developing a fully automatic optimized real-time controller for gas turbine engines.

The design life of fiberglass pipe is 50 years. In order to ensure long service life of fiberglass pipe, long-term properties under service conditions is the most important performance. According to the polymer matrix composite material with viscoelastic properties, adopt equivalent principle and shift factors method combined with experiments to study the long term performance of fiberglass pipe, established a relatively simple for fiberglass pipes long-term performance prediction method. The experiments show that compliance of fiberglass pipe with all hoop winding increased by 148% after 50 years in 60% stress level.

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