Fangzhou Xia

@article{2024IEEETNNLS,

title = {SymPO:One-Pass Fault Prediction For Non-Stationary Dynamics},

author = {Yip Fun Yeung and Fangzhou Xia* and Mikio Furokawa and Takayuki Hirano and Kamal Youcef-Toumi},

year  = {2024},

date = {2024-01-01},

urldate = {2024-01-01},

journal = {IEEE Transactions on Neural Network and Learning Systems (under review)},

keywords = {Automation, Intelligence, Mechatronics, Method, Modeling & Simulation, Signal Processing, Theory},

pubstate = {forthcoming},

tppubtype = {article}

}

@article{2023IEEESensors,

title = {A Doppler Radar with a Sweeping Lock-in Demodulator for Machine Vibration Sensing},

author = {Lois Wampler^ and Fangzhou Xia^* and Yip Fun Yeung and Takayuki Hirano and Ali Alshehri and Mikio Furokawa and Kamal Youcef-Toumi},

doi = {10.1109/JSEN.2023.3325820},

year  = {2023},

date = {2023-10-31},

urldate = {2023-10-31},

journal = {IEEE Sensors Journal},

abstract = {Data-driven predictive maintenance of modern machinery has the potential to increase equipment lifespan and decrease manufacturing costs. Vibration analysis can effectively diagnose potential problems in machines. A Doppler radar can be used as a sensor that provides non-contact, inexpensive real-time machine vibration data collection without necessitating line-down time. Implementation with Software Defined Radio (SDR) allow easy adjustment of excitation signals based on application needs. Conventional Fast Fourier Transformation based vibration analysis requires large amounts of data to achieve high spectral resolution needed for fault detection, which can be inefficient and computationally too expensive. In this work, we propose to use a sweeping lock-in amplifier to achieve high frequency resolution with small amounts of data by processing windowed sections of Doppler-shifted radio signals. This algorithm can reliably measure the Doppler shift frequency corresponding to the travelling speed of a moving object and identify the frequency of oscillating target with small amplitude, with the latter widely present in machine vibration. The distinguishing condition of the two cases is mathematically derived. The proposed algorithm is studied in simulation with triangular displacement waveform for simplicity of analysis and sinusoidal waveform for generic applications. For experimental verification, speaker vibration at a known frequency is analyzed to achieve an accuracy of 0.025 Hz within the known vibration frequency. This method is robust to the presence of noise frequencies and capable of detecting multiple frequencies.},

keywords = {Automation, Experimentation, Instrumentation, Mechatronics, Modeling & Simulation, Sensor, Signal Processing, Theory},

pubstate = {published},

tppubtype = {article}

}

@article{2021Mechatronics,

title = {A Modular Low-cost Atomic Force Microscope for Precision Mechatronics Education},

author = {Fangzhou Xia* and James Edwin Quigley and Xiaotong Zhang and Chen Yang and Yi Wang and Kamal Youcef-Toumi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0957415821000441},

issn = {0957-4158},

year  = {2021},

date = {2021-01-01},

urldate = {2021-01-01},

journal = {Mechatronics},

volume = {76},

pages = {102550},

publisher = {Elsevier},

abstract = {Precision mechatronics and nanotechnology communities can both benefit from a course centered around an Atomic Force Microscope (AFM). Developing an AFM can provide precision mechatronics engineers with a valuable multidisciplinary hands-on training experience. In return, such expertise can be applied to the design and implementation of new precision instruments, which helps nanotechnology researchers make new scientific discoveries. However, existing AFMs are not suitable for mechatronics education due to their different original design intentions. Therefore, we address this challenge by developing an AFM intended for precision mechatronics education.



This paper presents the design and implementation of an educational AFM and its corresponding precision mechatronics class. The modular educational AFM is low-cost (<4,000$) and easy to operate. The cost reduction is enabled by new subsystem development of a buzzer-actuated scanner and demodulation electronics designed to interface with a myRIO data acquisition system. Moreover, the use of an active cantilever probe with piezoresistive sensing and thermomechanical actuation significantly reduced experiment setup overhead with improved operational safety. In the end, the developed AFM capabilities are demonstrated with imaging results. The paper also showcases the course design centered around selected subsystems. The new AFM design allows scientific-method-based learning, maximizes utilization of existing resources, and offers potential subsystem upgrades for high-end research applications. The presented instrument and course can help connect members of both the AFM and the mechatronics communities to further develop advanced techniques for new applications.},

keywords = {Atomic Force Microscopy, Design, Education, Experimentation, Instrumentation, Mechatronics, Nanorobotics, Signal Processing},

pubstate = {published},

tppubtype = {article}

}