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Professor Ketema's research broadly focuses in the area of dynamics. He has studied the dynamics of active materials such as shape memory alloys, especially regarding their use for the purpose of vibration damping and control. Professor Ketema has also done research in optimal trajectory generation for unmanned aerial vehicles, dynamics and stability of formations, orbital mechanics, and the mechanics of human walking. In particular, current research topics include optimal transfers between relative orbits of space vehicles, and the use of kinetic models of human gait for step-size determination for use in pedestrian navigation systems and related applications. 

Education

Ph.D., Royal Institute of Technology, Stockholm, Sweden, 1992

Licentiate of Engineering: Royal Institute of Technology, Stockholm, Sweden, 1989

Masters of Science: Royal Institute of Technology, Stockholm, Sweden, 1987

Professional Background

Director of Undergraduate Studies, Aerospace Engineering and Mechanics, University of Minnesota, 2020-present

Contract Associate Professor, Aerospace Engineering & Mechanics, University of Minnesota, 2003-present

Director of Undergraduate Studies, 2003-2004

Contract Assistant Professor, Aerospace Engineering & Mechanics, University of Minnesota, 1993-2003

Teaching Assistant, Royal Institute of Technology, Stockholm, Sweden, 1986-1993

Research Engineer, Royal Institute of Technology, Stockholm, Sweden, 1993

Scientific & Professional Societies

Teaching Subjects

• AEM 2011 -- Statics
• AEM 3031 -- Deformable Body Mechanics
• AEM 4301 -- Orbital Mechanics
• AEM 5401 -- Intermediate Dynamics
• AEM 8495 -- Selected Topics in Dynamical Systems and Controls

Currently Teaching Courses

• AEM 4601 -- Instrumentation Laboratory
• AEM 8411 -- Advanced Dynamics |

Honors and Awards

2019: AIAA Associate Fellow

2010: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota 

2008: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

2007: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

2005: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

2002: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

1999: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

1997: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

1996: Outstanding Instructor Award, Institute of Technology Student Board, University of Minnesota

Selected Publications

“Y. Ketema, 2021, A Mass-optimized Gravity Tractor for Asteroid Deflection, arXiv, Vol. 136, pp. 64-79, 2021 (Submitted to Journal of Guidance, Control, and Dynamics)

Y. Ketema, 2017, Asteroid Deflection Using a Spacecraft in Restricted Keplerian Motion, Acta Astronautica, Vol. 136, p. 64-79, (Journal Article) 

Y. Ketema, D. Gebre-Egziabher, M. Schwartz, R. Kirker, and C. Matthews, 2014, Use of Gait Kinematics in Sensor Based Gait Monitoring: A Feasibility Study, Journal of Applied Mechanics, Vol. 81, Issue 4, (Journal Article)

Y. Ketema and Y.J. Zhao, 2010, Controllability and Reachability for Micro-Aerial-Vehicle Trajectory Planning in Winds, Journal of Guidance, Control, and Dynamics,, 33, 3, (Journal Article) 

Y. Ketema and Y.J. Zhao, 2010, Micro Air Vehicle Trajectory Planning in Winds, Journal of Aircraft, 47, 4, (Journal Article) 

Ketema Y., 2009, Optimal Satellite Transfers Using Relative Motion Dynamics, Journal of Guidance Control and Dynamics, 32, 5, 1508-1518, (Journal Article) 

Ketema, Y. (2022). Mass-Optimized Gravity Tractor for Asteroid Deflection. Journal of Guidance, Control, and Dynamics, 45(12), 2318-2331. (Journal Article) 

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