Ph.D. Mechanical Engineering, University of Utah (2019)
M.S. Mechanical Engineering, University of Utah (2018)
B.S. Mechanical Engineering, Brigham Young University (2016)
Email: Jon.Mortensen@utah.edu
LinkedIn: https://www.linkedin.com/in/jon-mortensen/
Phone: 801-581-6441
Lab: MEB 2215
We have several exciting projects using OpenSim to explore workplace exposures and injuries. OpenSim is an open source musculoskeletal modeling platform maintained by Standford University (NCSRR).
Concussion Risk in Sports
We have been developing a custom OpenSim model of the head and neck, which has recently been published. This new head and neck model is the first OpenSim model to have realistic strength in all directions, which we believe will useful for many areas of research. We are using this model to explore the effect of active neck muscles on concussion risk in American football. To this end we have developed optimization strategies to predict muscle activations that stiffen the neck as much as possible while maintaining posture. This work was presented at the SB3C and the ASB conferences in Arizona and Colorado. This work was has also been published in the Journal of Biomechanics. We are currently exploring the effect of muscle properties, include activation patterns, on head injury risk during impacts. The beginnings of this work has been presented at WCB in Ireland.
Slips, Trips, and Falls – Traumatic Brain Injury (TBI)
We are also currently using our OpenSim model to explore the effects of active neck muscles during slips and falls. The beginning of this work has been presented this summer at IEA in Italy. We have simulated falls that involve head impact with and without active neck muscles. Our work agrees with the literature in that active neck muscles have the capability to prevent or mitigate head injury. We hope to determine necessary neck strength, reaction time, and bracing strategies that will be useful for elderly and worker populations.
WBV and Neck Pain/Fatigue
We are simulating truck driver posture, and the effect of WBV on neck muscle fatigue and joint loading. We have demonstrated that WBV requires higher neck muscle activations, and that the increase is much more dramatic when the driver adopts a poor posture. We have recently submitted pilot grants to further this research, but expect to learn valuable insights on how posture and WBV may result in truck driver neck pain.
Upper Extremity Analysis – RULA
Another ergonomics application of OpenSim in our lab involves using a model of the upper extremity. We have simulated postures and loading that corresponds to different risk scores as determined by RULA. OpenSim allows us to compare muscle activation, joints loading (with active muscles), and many other biomechanical metrics to these RULA scores. We will be presenting our work at CHASE 2018, describing results that indicate that joint loading seems to compare to RULA quite well. We hope that this work will result in a simple online tool that offers more resolution and higher flexibility than RULA.
Sports performance
Using our background in musculoskeletal modeling and optimization techniques, we are exploring the effect of individual muscle characteristics on free throw shooting performance in basketball. Our preliminary results have been presented at RMASB in Colorado.
Research Interests: Biomechanics, Assistive Technology and Devices, Optimization, Human Factors Engineering
Research Project: The Effect of Active Neck Muscles on Head Injury Risk in American Football
Personal Interests: I spend my free time with my family, playing sports (basketball, racquetball and ultimate frisbee are my favorites), and watching sports. I’m starting to become a Utah Football Fan (the BYU Cougars make it easy sometimes). I look forward to using what I am learning in school to make this world a better place.