Todd Letcher

Title

Associate Professor

Office Building

Crothers Engineering Hall

Office

212

Mailing Address

Crothers Engineering Hall 212
Mechanical Engineering-Box 2219
University Station
Brookings, SD 57007

Biography

Todd Letcher received his Ph.D. from the Ohio State University in mechanical engineering in 2012. Since then, he has served as a postdoctoral researcher with the SDSU METLAB, a lecturer, an assistant professor and now associate professor in the mechanical engineering department at SDSU. His research focuses on developing knowledge and technologies that allow 3D printing techniques to be used for end-use manufacturing. Dr. Letcher is also an associate director of the South Dakota Space Grant Consortium, which has developed into a new research area - space robotics. Dr. Letcher is also very interested in engineering entrepreneurship and is part of the NSF I-Corps Hub for the Great Plains Region.

Dr. Letcher currently teaches Engineering Design Methods, Mechanical Systems Design I and II. These classes allow students to design solutions to open ended problems and typically involved designing, building, and testing their solutions. Dr. Letcher also advises many senior design projects, independent study projects and several graduate students.

Social Media Links

Education

B.S. in mechanical engineering | South Dakota State University | 2005
M.S. in mechanical engineering | Ohio State University | 2008
Ph.D. in mechanical engineering | Ohio State University | 2012

Academic Interests

Additive manufacturing/3D printing
Off-earth robotics
Engineering entrepreneurship
Experimental mechanics
Materials characterization
Solid mechanics
Design optimization

Academic Responsibilities

ME 230 - Engineering Design Methods
ME 478/479 - Mechanical Systems Design I/II (Senior Design Capstone course sequence)
ME 490 - Design Seminar

Past Academic Responsibilities

ME 121 - Production and Manufacturing Processes
ME 212 - Mechanical Engineering Design Technologies
ME 240 - Introduction to Mechanical Design
ME 321 - Fundamentals of Machine Design
ME 376 - Measurements and Instrumentation Lab
ME 741 - Advanced Stress Analysis

Committees and Professional Memberships

Committees

Mechanical Engineering Department Laboratory Committee
College of Engineering Promotion and Tenure Committee

Professional Memberships

American Society of Mechanical Engineers (ASME)
American Society for Engineering Education (ASEE)

Awards and Honors

August 2023, NASA FLOATing DRAGON Finalist.
June 2023, 1st Place in Lunar Transport Vehicle at NASA RASC-AL.
December 2022, NASA's Break the Ice Lunar Challenge - Invited to Phase 2, Level 2, Space Trajectory (Team Leader).
September 2021, Clearest Water Award Winner, NASA's Moon to Mars Ice and Prospecting Challenge (Team Leader).
August 2021, Runner Up Award for NASA's Break the Ice Lunar Challenge Phase 1, Space Trajectory (Team Leader).
April 2020, Jerome J. Lohr College of Engineering Young Investigator of the Year.
March 2019, ASME IAM3D Challenge 2019 West 1st Place (Advisor).
April 2017, Jerome J. Lohr College of Engineering Advisor of the Year.
April 2014, Student’s Choice for Teacher of the Year in Mechanical Engineering at South Dakota State University.
May 2012, ASME IGTI Young Engineers Travel Award.

Grants

Letcher, T., Kavasseri, R., NSF I-Corps Hub: Great Plains Region, NSF I-Corps Hub Program.
Letcher, T., Messerli, M. “Investigating Green and Renewable Polymers to Combat Drought,” North Central Region Sun Grant.
Bruno, N., Kharel, Letcher, T. “Advanced Soft-Magnetic Materials for Electrified Propulsion” NASA EPSCoR.
McKillip, A., Cutler, K. Letcher, T., Silvernagel, C., “Living and Working in Space - Children’s Museum Traveling Exhibit Design”.
Letcher, T. “In-Situ Resource Utilization NASA Challenges” SD Space Grant Consortium".
Ciarcia, M., Letcher, T. “Design, Development, and Testing of an Advanced Multirotor for Human Transportation”.
Letcher, T. “South Dakota Space Grant Consortium 2020-2024”.
Letcher, T. “Dynamic Aluminum Embedment in Bolted Joints” August 21, 2020 to August 31, 2021. Private Industry - Matrix Engineering.
Letcher, T., Prasad, A. “Additively Manufactured GRCop Extended Investigation” NASA EPSCoR Rapid Response.
Letcher, T., Prasad, A. “Characterization of GRCop-42 Additively Manufactured Material” NASA EPSCoR Rapid Response.
Letcher, T. “Thermal Protection System Testing” NASA Marshall/University of Alabama Huntsville.
Letcher, T. “Development of Novel Feedstocks for In-Space Manufacturing Applications” NASA Exploration Systems and Habitation Academic Innovation Challenge 2019.
Letcher, T., Burckhard, S. “3D Printed Habitat Challenge Extension” SD Space Grant Consortium.
Letcher, T., Michna, G. “Advanced Materials for 3D printable heat exchangers” SD Space Grant Consortium.
Michna, G., Letcher, T. “Startup of South Dakota State University CubeSat Club” SD Space Grant Consortium.
Gent, S., Letcher, T. “Initial Engineering Analysis of KB Balance Trainer”.
Letcher, T. "Investigating Paint Embedment in Dynamic Bolted Connection - Phase 2".
Letcher, T. "Investigating Paint Embedment in Dynamic Bolted Connection - Phase 1".
Messerli, M., Letcher, T. “Constructing a Prototype for Automated Pancreatic Islet Sorting and Screening” SD Board of Regents Competitive Research Grant Program FY17.
Letcher, T., Michna, G. “3D printable heat exchangers to enhance student learning related to space science” SD Space Grant Consortium Project Innovation Grant.

Patents

McKillip, A., Letcher, T., Lucchesi, R., Silvernagel, C., Heller, B., Cutler, K. and Gottsleben, T. (2022). U.S. Patent Application No. 29/713,541
Miller, K. S., Letcher, T. M., Nearman, N. L., Munson, L. A. and Fuls, C. L. (2010). U.S. Patent No. 7,694,444. Washington, DC: U.S. Patent and Trademark Office

Areas of Research

Additive Manufacturing
3D Printer Hardware Development
3D Printer Material Development
3D Printed Material Characterization
Design for Additive Manufacturing

Publications

Landes, S., Letcher, T. "Mechanical strength of bamboo filled PLA composite material in fused filament fabrication." Journal of Composites Science 4.4 (2020): 159.
Amatya, I., Seo, J., Letcher, T., & Bierschbach, D. "Tensile-and shear-strength tests with adhesive connections in dynamic message signs." Journal of Materials in Civil Engineering 33.6 (2021): 04021131.
McTaggart, R., Rankouhi, B. & Letcher, T. “Effects of gamma irradiation on mechanical properties of 3D-printed carbon fiber–reinforced ABS.” Int J Adv Manuf Technol (2020). DOI: 10.1007/s00170-020-06243-4.
Amatya, Ibin, Seo, J., Letcher, T., Ahn, JH. "Peel and cleavage strength tests with adhesive connections in dynamic message signs." International Journal of Adhesion and Adhesives 103 (2020): 102715.
Coughlin, N., Drake, B., Fjerstad, M., Schuster, E., Waege, T., Weerakkody, A., & Letcher, T. (2019). Development and mechanical properties of basalt fiber-reinforced acrylonitrile butadiene styrene for in-space manufacturing applications. Journal of Composites Science, 3(3), 89.
West, C., McTaggart, R., Letcher, T., Raynie, D., & Roy, R. (2019). Effects of gamma irradiation upon the mechanical and chemical properties of 3D-printed samples of polylactic acid. Journal of Manufacturing Science and Engineering, 141(4).
Silvernagel, C., Letcher, T., McKillip, A., Nester, J., Cutler, K. “Work-in-Progress: The Transformative Cauldron, Development of the Optimal Space-in-Between” ASEE 2022 Annual Conference
Landes, S., Suresh, T., Prasad, A., Letcher, T., Gradl, P, Ellis, D. “Investigation of Additive Manufactured GRCop-42 Alloy Developed by Directed Energy Deposition Methods” ASME IMECE Conference 2020, IMECE2020-24400
Landes, S., Suresh, T., Prasad, A., Letcher, T., Gradl, P, Ellis, D. “Nanomechanical Characterization of Additive Manufactured GRCop-42 Alloy Developed by Directed Energy Deposition Methods” ASME IMECE Conference 2020, IMECE2020-23382
Smithee, I., Berg, S., Olson, W., Twedt, R., Runge, N., Letcher, T., Ciarcia, M. Design, Development, and Testing of an Autonomous Multirotor for Personal Transportation. 2020 USCToMM Symposium on Mechanical Systems and Robotics
Pereira, L., Letcher, T., Michna, G. The Effects of 3D Printing Parameters and Surface Roughness on Convective Heat Transfer Performance. Summer Heat Transfer Conference 2017, Bellevue, Washington, July 14-17, 2019.

Department(s)

Image for Department of Mechanical Engineering
Department of Mechanical Engineering
Image for Materials Evaluation and Testing Laboratory
Materials Evaluation and Testing Laboratory