Academic Credentials
  • Ph.D., Mechanical Engineering, California Institute of Technology (Caltech), 2017
  • M.S., Mechanical Engineering, California Institute of Technology (Caltech), 2014
  • B.S., Mechanical Engineering, Milwaukee School of Engineering, 2008
Licenses & Certifications
  • Professional Engineer Mechanical, California, #39478
  • 40-Hour Hazardous Waste Operation and Emergency Response Certification (HAZWOPER)
  • Certified Forklift Operator (CFO)
  • IFPS Certified Fluid Power Hydraulic Specialist, Certificate
  • OSHA #511 Occupational Safety and Health Standards for General Industry
  • PADI Certified Open Water Scuba Diver
Professional Honors
  • NASA Aeronautics Fellowship, 2010
  • American Society of Mechanical Engineering, Foundation Gratitude Scholarship, 2009
Professional Affiliations
  • American Society of Mechanical Engineers (member)
  • International Fluid Power Society (member)
  • American Society of Testing and Materials
    • Committee F15 - Consumer Products (member)
    • Committee F42 - Additive Manufacturing Technologies (member)

Dr. Zelhofer specializes in the development, evaluation, and failure analysis of industrial equipment and consumer products. He has applied his expertise to analyses involving hydraulic equipment, manual and automated industrial machines, vehicle associated equipment, micromobility vehicles (e.g. electric scooters and bicycles), exercise equipment, industrial and consumer tools, and chairs. 

Dr. Zelhofer's experience spans industrial sector advisor, litigation consultant, and academic lecturer. Specific examples of his experience include:

    • Hydraulic equipment used in the construction and automotive industries including hydraulic pistons, floor jacks, bottle jacks, and hand pumps.
    • Industrial equipment used in warehouses, construction, and food processing industries including automated equipment, forklifts, reach trucks, industrial vats, food processing equipment, scaffolding, and conveyors.
    • Vehicle associated equipment either located on the vehicle or used as part of normal operation or maintenance including jack stands, tailgates, winches, loading ramps, dock levelers, and gas fuel nozzles.
    • Micromobility vehicles commonly seen in urban areas including electric standing scooters, electric seated scooters, and electric bicycles.
    • Exercise equipment used in condominiums and public gyms including strength training equipment, selectorized equipment, and stationary bikes.
    • Industrial and consumer tools used in the construction, fabrication, machining, and agriculture industries including grinding wheels, mills, lathes, saws, drills, nailers, grinders, sanders, air compressors, generators, brush mowers, and tillers.
    • Chairs used in public areas and private residences including waiting rooms, casinos, and sporting events.

In the course of evaluation and failure analysis Dr. Zelhofer performs both non-destructive and destructive techniques of investigation. For non-destructive evaluation he frequently uses 3D scanning via LiDAR (light detection and ranging) and CT (computerized tomography), 2D X-ray, and dimensional measurement using a coordinate measuring machine (CMM). For destructive evaluation Dr. Zelhofer frequently employs his extensive woodworking and metalworking knowledge coupled with his expertise in machine design to dissect and/or test items of focus. He is frequently called upon to conduct destructive testing in high load applications.