We are developing a set of wearable direct-read PM mass sensors for measuring respirable (PM4.0) and aveolar (PM1.0) mass fraction of dust in underground coal mines. The project test the limits of the development of a PM direct-read mass sensor that can operate at a large dynamic range, and that is intrinsically safe. The technology that is developed in this project has many application PM mass sensors in general, due to variable environmental conditions in the underground coal mine. The developed sensor designs will be MSHA certifiable to be used in underground coal mines.

Sponsor:

• National Institute for Occupational Safety and Health (NIOSH), Center for Disease Control and Prevention (CDC)

The project aims to develop a personal wearable Particulate Matter (PM) sensor platform. Among recent results, we have developed a limited number of prototype evaluation kits. The unique fabrication methods developed as part of this project allows us to produce a direct-read mass PM sensor with superior footprint and cost, ideal suited for wearable devices.

Sponsor:

• Kanomax Inc.

Selected Publications:

• Fahimi D., O. Mahdavipour, T. Cados, T. Kirchstetter, P. Solomon, R. M. White, L. Gundel, and I. Paprotny, “MEMS Air-Microfluidic Lab-on-a-chip Sensor for Personal Monitoring of Airborne Particulate Matter (PM2.5).”, in the Technical Digest of the Hilton Head Workshop 2016: A Solid-State Sensors, Actuators and Microsystems Workshop, June 2016.
• Dorsa Fahimi, Omid Mahdavipour, Paul A. Solomon, Lara Gundel, Richard White, Igor Paprotny. “PM Badge: A Wearable, Low-Power, Cellular-Enabled, Direct-Read Mass MEMS PM2.5 Sensor.” in Proc. of the 35th Annual Conference for the American Association of Aerosol Research (AAAR 2016), Portland, OR.

We are researching untethered aerial (flying) microrobots. We envision these devices to soar akin to controllable (steerable) specs of dust floating through the air. The applications include, among others, surveillance, distributed remote imaging, microassembly, and chemical analysis. We have demonstrated untethered microscale flight of 300 µm x 300 µm sized stress-engineered microfliers. We are currently exploring stability and control as well as biomimetic propulsion for microscale flying robots.

Sponsor:

• National Science Foundation

Selected Publications:

• S. A. Hussain, A. Klitzke, R. Majumdar, and I. Paprotny, “Analysis and Experimental Results of Untethered Flight of Stereolithographically Printed MEMS Microfliers.”, in the Technical Digest of the Hilton Head Workshop 2016: A Solid-State Sensors, Actuators and Microsystems Workshop, June 2016
• S. Ward, V. Foroutan, R. Majumdar, O. Mahdavipour, S. A. Hussain, and I. Paprotny, “Towards Microscale Flight: Fabrication, Stability Analysis, and Initial Flight Experiments for 300 micrometer × 300 micrometer Sized Untethered Microfliers,” IEEE Transactions on Nanobioscience, 14(3), 2015: 323 – 331.

Sensors for Automated Control of Coal Dust (SACCD) are devices that will form an integrated wireless network that automatically measures the total incombustible content of the deposited dust stack (approximately ratio of inert rock dust to coal dust) and indicates when this ratio is below or above the explosibility threshold, i.e., insufficient rock dust is present in the mixture. The data will be continuously relayed to the mine operator.

Sponsor:

• National Institute for Occupational Safety and Health

Selected Publications:

• Omid Mahdavipour, John Sabino, Timothy Mueller-Sim, Michael R. Shahan, Clara E. Seaman, Paul A. Solomon, Paul Wright, Richard White, Lara Gundel, Larry D. Patts, Igor Paprotny. “Opto-Dielectrometric Sensors for Automated Control of Total Incombustible Content in Underground Coal Mines.” in Proc. of the 35th Annual Conference for the American Association of Aerosol Research (AAAR 2016), Portland, OR.
• Mahdavipour, O., T. Mueller-Sim, D. Fahimi, S. Croshere, V. Zegna, J. Sabino, P. Pillatsch, J. Merukh, P. A. Solomon, P. Wright, R. M. White, L. Gundel, and I. Paprotny. “Distributed Sensors for Automated Control of Total Incombustible Content (TIC) of Dust Deposited in Underground Coal Mines” in the Proceedings of the 14th Annual IEEE Conference on Sensors (IEEE SENSORS 2015), November 1-4 2015, Busan, South Korea.

Increasingly more attention is being directed at developing pervasive methods of detecting and monitoring emissions from natural gas infrastructures and production sites. Existing methane detection methods are expensive, require high power to operate, have low selectivity, or can be saturated (poisoned) by other gasses. In recent years, functionalized carbon nanotube (CNT) based sensors have emerged as a highly sensitive alternative to electrochemical gas sensors. This project is to develop a low-cost/low-power, highly sensitive, and highly selective CNT based methane sensor that can be used in leak detection of natural gas infrastructures. In addition, similar chemistry of certain VOC gases has been utilized to detect VOC.

Sponsors:

• U.S. Department of Energy
• Kanomax

Selected Publications:

• M. T. Humayun, R. Divan, Y. Liu, L. Gundel, P. A. Solomon,and I. Paprotny “Novel chemoresistive CH₄ sensor with 10 ppm sensitivity based on multi-walled carbon nanotubes (MWCNTs) functionalized with SnO₂ nanocrystals,” submitted to Journal of Vacuum Science and Technology A (JVST A), 34, 01A131, 2016, DOI:http://dx.doi.org/10.1116/1.4936384.
• Sainato, M., M. T. Humayun, L. Gundel, P. Solomon, L. Stan, R. Divan, I. Paprotny, “Parts Per Million CH₄ Chemoresistor Sensors Based on Multi Wall Carbon Nanotubes/Metal-oxide Nanoparticles.” in the Proceedings of the 15th Annual IEEE Conference on Sensors (IEEE SENSORS 2016), October 30 – November 2nd 2016, Orlando, FL.

This is ongoing work within AMFG to understand the phenomenon and develop new models and instruments to model how particles flow within air-microfluidic circuits. The goal is to develop analytical and Finite Element Method (FEM) models and interrogation methods for particles flow at very low flow rates in microfabricated channels, understand the charging phenomena. The methods developed in this work will lead to better tools for air-microfluidic circuits.

Selected Publication:

• Mahdavipour, O. , B. Gould, D. Fahimi, D. Liederman, S. Ward, D. S. Nguyen, D. Woolsey, P. A. Solomon, R. M. White, L. A. Gundel, and I. Paprotny “How Small Can We Go: Exploring the Limitations and Scaling laws of Air-Microfluidic Particulate Matter Sensors.” In Proc. 33rd Conference for the American Association for Aerosol Research (AAAR 2014), October 20-24, Orlando, FL