atypical Gait analysis with IMU

[Rachel Hybart]

Hello,
I am working on analyzing some gait data using APDM Opals (one on each foot and one on the lumbar spine), and wanted to see if there is any code out there to find gait events, as well as step length for atypical gait.
My participants are walking with an ankle exoskeleton which means some of my the points of interest in my gait may not follow typical gait patterns.
Any help is greatly appreciated.
Thank you
Rachel Hybart
University of Florida

[Edmund Cramp]

I'd suggest talking with the sensor manufacturer. There are a lot of gait event calculation methods documented based on 3D location analysis but that is a different data environment. Gait events are relatively easy to measure for normal gait with heel contact and toe contact data, but atypical gait can result in very different data; for some subjects with clinical issues, a heel may never touch the floor, while occasionally a subjects' toe only slides along the floor. Adding force plate data to the analysis would help verify it.

[Meredith Evans]

Hi Rachel,

As Eddie Cramp suggested some of the typical gait events become a problem for a-typical gait. We integrated the APDM sensors with The MotionMonitor several years ago and as you can see in the example below our typical algorithms work well to detect gait events. But we have found additional tools are needed to deal with a-typical gait. TMM allows the user to easily exclude particular steps, so you can trim the data if needed. Most importantly, the user has the ability to see and modify the gait detection algorithms, so you can make changes if it’s necessary for your population. You can also synchronously collect from force plates within The MotionMonitor and use this to verify or augment the gait algorithms. TMM also collects other motion capture hardware synchronously, so you could compare with a 3D system, including marker-based & markerless. Please feel free to reach out to us if you’d like to take a look.

Good luck with your study!

Meredith Evans
mevans@TheMotionMonitor.com
The MotionMonitor, Innovative Sports Training, Inc.
Gait Statistics Workspace.jpg