Scanning Probe Microscopy
Probe Based Lithography
Probe based lithography involves creating nanometer sized features from photoresist and metal on conducting and semiconducting substrates. Near field optical, electrical and thermal fields are employed in combination with evaporation, etching and electroplating to provide high-speed alternatives for mask-less nanofabrication.
Nanopositioning
A nanopositioner is a electromechanical device for moving objects in three dimensions with atomic, or sub-atomic resolution. Nanopositioners are employed in applications such as imaging, fabrication and optics. This field encompasses mechanical design, sensor design, and control theory. More details.
Electroactive Optics
Piezoelectric actuators can be combined with mirrors, lenses and objectives to actively control the path and properties of an optical field or laser beam. High speed electro-optics are required for precision lasers, maskless lithography, and microscopy.
Precision Sensors
This project aims to study the fundamental limitations of capacitive, optical and magnetic position sensors. New techniques are under development to provide sub-atomic resolution over extremely wide bandwidth.
Biomedical Devices
An endoscopic pill robot is being developed for noninvasive imaging and intervention. The robot can be swallowed and includes power transmission, 6-Dimensional localization, and locomotion.
Piezo Actuators and Amplifiers

Piezo bender actuator with integrated 200V power electronics
Piezo Robotics
Due to their compact size and high efficiency, piezoelectric actuators are ideal for micro-actuation in bio-inspired robotics. This project is developing actuators and mechanics for a piezoelectric dragon-fly robot.
Yong, Y. K.; Eielsen, A. A.; Fleming, A. J.
Thermal Protection of Piezoelectric Actuators Using Complex Electrical Power Measurements and Simplified Thermal Models Journal Article
In: IEEE/ASME Transactions on Mechatronics (Early Access), 2023.
@article{Yong2023,
title = {Thermal Protection of Piezoelectric Actuators Using Complex Electrical Power Measurements and Simplified Thermal Models},
author = {Y. K. Yong and A. A. Eielsen and A. J. Fleming},
doi = {10.1109/TMECH.2023.3277437},
year = {2023},
date = {2023-06-05},
urldate = {2023-06-05},
journal = {IEEE/ASME Transactions on Mechatronics (Early Access)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Xavier, M. S.; Harrison, S.; Howard, D.; Yong, Y. K.; Fleming, A. J.
Modeling of soft fluidic actuators using fluid-structure interaction simulations with underwater applications Journal Article
In: International Journal of Mechanical Sciences, 2023.
@article{Xavier2023,
title = {Modeling of soft fluidic actuators using fluid-structure interaction simulations with underwater applications},
author = {M. S. Xavier and S. Harrison and D. Howard and Y. K. Yong and A. J. Fleming},
url = {https://www.precisionmechatronicslab.com/wp-content/uploads/2023/06/FSI.pdf},
doi = {https://doi.org/10.1016/j.ijmecsci.2023.108437},
year = {2023},
date = {2023-05-15},
urldate = {2023-05-15},
journal = {International Journal of Mechanical Sciences},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

McCourt, L. R.; Routley, B. S.; Ruppert, M. G.; Keast, V. J.; Sathish, C. I.; Borah, R.; Goreham, R. V.; Fleming, A. J.
In: ACS Applied Nano Materials, vol. 5, iss. 7, pp. 9024-9033, 2022, ISSN: 2574-0970.
@article{nokey,
title = {Single-Walled Carbon Nanotubes as One-Dimensional Scattering Surfaces for Measuring Point Spread Functions and Performance of Tip-Enhanced Raman Spectroscopy Probes},
author = {L. R. McCourt and B. S. Routley and M. G. Ruppert and V. J. Keast and C. I. Sathish and R. Borah and R. V. Goreham and A. J. Fleming},
url = {https://www.precisionmechatronicslab.com/wp-content/uploads/2023/02/J22i.pdf},
doi = {10.1021/acsanm.2c01274},
issn = {2574-0970},
year = {2022},
date = {2022-06-21},
urldate = {2022-06-21},
journal = {ACS Applied Nano Materials},
volume = {5},
issue = {7},
pages = {9024-9033},
abstract = {This Article describes a method for the characterization of the imaging performance of tip-enhanced Raman spectroscopy probes. The proposed method identifies single-walled carbon nanotubes that are suitable as one-dimensional Raman scattering objects by using atomic force microscope maps and exciting the radial breathing mode using 785 nm illumination. High-resolution cross sections of the nanotubes are collected, and the point spread functions are calculated along with the optical contrast and spot diameter. The method is used to characterize several probes, which results in a set of imaging recommendations and a summary of limitations for each probe. Elemental analysis and boundary element simulations are used to explain the formation of multiple peaks in the point spread functions as a consequence of random grain formation on the probe surface.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Ragazzon, M. R. P.; Messineo, S.; Gravdahl, J. T.; Harcombe, D. M.; Ruppert, M. G.
The Generalized Lyapunov Demodulator: High-Bandwidth, Low-Noise Amplitude and Phase Estimation Journal Article
In: IEEE Open Journal of Control Systems, 2022.
@article{Ragazzon2022,
title = {The Generalized Lyapunov Demodulator: High-Bandwidth, Low-Noise Amplitude and Phase Estimation},
author = {M. R. P. Ragazzon and S. Messineo and J. T. Gravdahl and D. M. Harcombe and M. G. Ruppert},
doi = {10.1109/OJCSYS.2022.3181111},
year = {2022},
date = {2022-06-08},
urldate = {2022-06-08},
journal = {IEEE Open Journal of Control Systems},
abstract = {Effective demodulation of amplitude and phase is a requirement in a wide array of applications. Recent efforts have increased the demodulation performance, in particular, the Lyapunov demodulator allows bandwidths up to the carrier frequency of the signal. However, being inherently restricted to first-order filtering of the input signal, it is highly sensitive to frequency components outside its passband region. This makes it unsuitable for certain applications such as multifrequency atomic force microscopy (AFM). In this article, the structure of the Lyapunov demodulator is transformed to an equivalent form and generalized by exploiting the internal model principle. The resulting generalized Lyapunov demodulator structure allows for arbitrary filtering order and is easy to implement, requiring only a bandpass filter, a single integrator, and two nonlinear transformations. The generalized Lyapunov demodulator is implemented experimentally on a field-programmable gate array (FPGA). Then it is used for imaging in an AFM and benchmarked against the standard Lyapunov demodulator and the widely used lock-in amplifier. The lock-in amplifier achieves great noise attenuation capabilities and off-mode rejection at low bandwidths, whereas the standard Lyapunov demodulator is shown to be effective at high bandwidths. We demonstrate that the proposed demodulator combines the best from the two state-of-the-art demodulators, demonstrating high bandwidths, large off-mode rejection, and excellent noise attenuation simultaneously.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Xavier, M. S.; Tawk, C. D.; Zolfagharian, A.; Pinskier, J.; Howard, D.; Young, T.; Lai, J.; Harrison, S.; Yong, Y. K.; Bodaghi, M.; Fleming, A. J.
Soft Pneumatic Actuators: A Review of Design, Fabrication, Modeling, Sensing, Control and Applications Journal Article
In: IEEE Access, vol. 10, pp. 59442-59485, 2022, ISSN: 2169-3536.
@article{J22h,
title = {Soft Pneumatic Actuators: A Review of Design, Fabrication, Modeling, Sensing, Control and Applications},
author = {M. S. Xavier and C. D. Tawk and A. Zolfagharian and J. Pinskier and D. Howard and T. Young and J. Lai and S. Harrison and Y. K. Yong and M. Bodaghi and A. J. Fleming},
url = {https://www.precisionmechatronicslab.com/wp-content/uploads/2023/02/J22h-1.pdf},
doi = {10.1109/ACCESS.2022.3179589},
issn = {2169-3536},
year = {2022},
date = {2022-06-02},
urldate = {2022-06-02},
journal = {IEEE Access},
volume = {10},
pages = {59442-59485},
abstract = {Soft robotics is a rapidly evolving field where robots are fabricated using highly deformable materials and usually follow a bioinspired design. Their high dexterity and safety makes them ideal for applications such as gripping, locomotion, and biomedical devices, where the environment is highly dynamic and sensitive to physical interaction. Pneumatic actuation remains the dominant technology in soft robotics due to its low cost and mass, fast response time, and easy implementation. Given the significant number of publications in soft robotics over recent years, newcomers and even established researchers may have difficulty assessing the state of the art. To address this issue, this article summarizes the development of soft pneumatic actuators and robots up until the date of publication. The scope of this article includes the design, modeling, fabrication, actuation, characterization, sensing, control, and applications of soft robotic devices. In addition to a historical overview, there is a special emphasis on recent advances such as novel designs, differential simulators, analytical and numerical modeling methods, topology optimization, data-driven modeling and control methods, hardware control boards, and nonlinear estimation and control techniques. Finally, the capabilities and limitations of soft pneumatic actuators and robots are discussed and directions for future research are identified.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
