1 / 6

Test method for empirically determining inertial properties of manual wheelchairs

Test method for empirically determining inertial properties of manual wheelchairs. Matthew R. Eicholtz, MS; Jayme J. Caspall, MS; Phuc V. Dao, MS; Stephen Sprigle, PhD, PT; Al Ferri, PhD. Study Aim Design and study a method for empirically measuring inertia properties of manual wheelchairs.

btupper
Download Presentation

Test method for empirically determining inertial properties of manual wheelchairs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Test method for empirically determining inertial properties of manual wheelchairs Matthew R. Eicholtz, MS; Jayme J. Caspall, MS; Phuc V. Dao, MS; Stephen Sprigle, PhD, PT; Al Ferri, PhD

  2. Study Aim • Design and study a method for empirically measuring inertia properties of manual wheelchairs. • Relevance • Results will improve and generate new studies on wheelchair performance, especially during turning maneuvers, in which inertia is important.

  3. Methods • Used iMachine for tests. • Spring-loaded turntable for measuring inertial properties of irregularly shaped rigid bodies. • Calculated wheelchair mass and center of mass from static force measurements using load cells. • Used Newton-Euler approach. • Determined moment of inertia about vertical axis from natural frequency of system in simple harmonic motion. • Calibrated iMachine to eliminate effects of platform components on measurement error.

  4. Results • Average relative error: • Mass = 0.76% • Center of mass • x-axis = 0.89% • y-axis = 1.99% • Resolution of moment of inertia calculation depends on ratio of test piece inertia to system inertia:  ratio indicates =  measurement accuracy • Gage repeatability and reproducibility test with 3 manual wheelchairs: • Each completed 3 tests by 3 different operators. • 99% of inertia variance caused by wheelchair differences.

  5. Results Relative error vs inertia ratio (ratio of test piece inertia to total inertia of test piece and turntable).

  6. Conclusions • iMachine measurement system operation is acceptable for both inertia and mass measurement using criteria from Automobile Industry Action Group.

More Related