Torrence D. J. Welch

Torrence D. J. Welch, Ph.D.

Senior Managing Consultant

Dr. Welch holds a Ph.D. in Biomedical Engineering awarded jointly by the Georgia Institute of Technology (Georgia Tech) School of Engineering and the Emory University School of Medicine in Atlanta, GA.  His areas of expertise include the biomechanics of human injury, vehicle accident reconstruction, slip-and-fall events, occupational injury, reactive muscle activity, and human balance control and stability. Dr. Welch has offered expert testimony in the fields of accident reconstruction and injury biomechanics in Federal, State, and local Courts throughout the United States.

Dr. Welch has over 20 years of biomechanics research experience, studying human movement on multiple levels.

  • Injury – the forces present on the body during automotive collisions; mechanics – the effects of forces on the bony and soft tissues underlying human movement;
  • Coordination – the activation of muscles in functional groups called muscle synergies;
  • Control – the mechanisms used by the nervous system to control standing balance and to learn new balance tasks;
  • Performance – the effects of supplements on sport and exercise performance

He also has experience in human motion and gait analysis; electromyography (EMG); the computer modeling of biomechanical systems; the mechanical, biochemical, and ultrasound characterization of biological soft tissue; biomedical ultrasound imaging; and statistical and wavelet analysis. Dr. Welch performs biomechanical analyses for cases involving automotive collisions, slip/trip and fall events, falling objects, occupational injury, and other incidents leading to human injury. He performs vehicle accident reconstruction analyses for collisions involving single vehicles, multiple vehicles, and pedestrians. Dr. Welch is published in numerous publications on topics related to automotive collision-related injury and human standing balance control, and actively maintains collaborative research relationships with several academic institutions.


  • Flip-Flops: A Survey of Risk Perception and Acceptance, Proceedings of the 66th International Annual Meeting of the Human Factors and Ergonomics Society, October 2022
  • Beyond Causation: When to Use a Biomechanics Expert, The Prairie Barrister, July 2020
  • Beyond Causation: When to Use a Biomechanics Expert, Verdict, March 2019
  • Mechanisms of Motor Adaptation in Reactive Balance Control, PLoS ONE, January 2014
  • Statistically-Significant Contrasts Between EMG Waveforms Revealed Using Wavelet-Based Functional ANOVA, Journal of Neurophysiology, January 2012
  • An Evaluation of the Biorid II and Hybrid III ruring Low- wnd Moderate-Speed Rear Impact, SAE International Journal of Passenger Cars – Mechanical Systems, January 2010
  • Lumbar Loads in Low to Moderate Speed Rear Impacts, SAE Technical Paper 2010-01-0141, January 2010
  • An Evaluation of The Biorid II and Hybrid III during Low- and Moderate-Speed Rear Impact, SAE Technical Paper 2010-01-1031, January 2010
  • Neuromechanical Tuning of Nonlinear Postural Control Dynamics, Chaos, January 2009
  • A Feedback Model Explains the Differential Scaling of Human Postural Responses to Perturbation Acceleration and Velocity, Journal of Neurophysiology, January 2009
  • See CV for further publications

Home Office


430 Technology Parkway NW Peachtree Corners, GA 30092
  • Phone: (678) 990-3280
  • Fax: (678) 990-3285

Project Experience

ESi's expertise spans dozens of industries and specializations organized across several practice groups, each staffed by dozens of in-house experts with the technical knowledge, hands-on expertise, and courtroom experience required to execute projects for and with our clients from start to finish.

Contact Us