Date: 2/19/2025

Dataset Title: The Össur Power Knee with Phase-Based Control Provides Clinical Benefits over Passive Microprocessor Knees: Experiment Dataset

Dataset Contact: T. Kevin Best
Email: tkbest@umich.edu

Dataset Creators:
Name: T. Kevin Best
Email: tkbest@umich.edu
Institution: University of Michigan, Robotics Department

Name: C. Andrew Seelhoff
Institution: University of Michigan, Mechanical Engineering Department

Name: Jeffrey Wensman
Institution: University of Michigan, Orthotics and Prosthetics Center, Michigan Medicine

Name: Robert D. Gregg
Email: rdgregg@umich.edu
Institution: University of Michigan, Robotics and Mechanical Engineering Departments

Funding:
National Institute of Child Health & Human Development of the National Institutes of Health under Award R01HD094772
National Science Foundation under the Graduate Research Fellowship DGE 1841052
Prosthetic hardware and initial financial support from Össur hf (Reykjavík, Iceland).

Research Overview:
The dataset was collected to assess the clinical benefits of the latest generation Össur Power Knee with and without phase-based control compared to traditional passive microprocessor-controlled knees. The study included seven above-knee amputee participants and examined performance across a series of sit/stand and walking experiments. Data captured includes event logs, processed inverse kinematics and dynamics data, scaled OpenSim skeletons for each session, and raw motion capture and force plate data for various test conditions (HKIC, OSSR, PRES).

Methodology:
Participants were tested performing sit/stand and walking activities under three conditions: their prescribed passive prosthesis (PRES), the Power Knee with the standard control system (OSSR), and the Power Knee using a hybrid kinematic impedance controller (HKIC). Biomechanical data was collected using VICON motion capture systems and AMTI and Bertec force plates, with processing conducted in OpenSim 4.5.

The dataset is organized by subject and test condition. Each folder includes a scaled subject OpenSim skeleton (*_skeleton.osim), a marker file for a range of motion trial (*_range_of_motion.trc), and three test folders each containing:
Event Logs (*.event_log.csv): Time-stamped records of experimental events.
Inverse Kinematics Data (*_IK.mot): Joint angle trajectories.
Inverse Dynamics Data (*_ID.mot): Joint moment trajectories.
Raw Marker Data (*_markers.csv): 3D coordinates of motion capture markers.
Ground Reaction Force Data (*_GRF.mot): Force plate measurements of ground reactions during movement tasks.

Viewing the Data:
All files are text-based and can be opened in any compatible text editor. For visualization, the skeleton file, IK, ID, marker, and GRF data can all be viewed in OpenSim: https://simtk.org/projects/opensim.

Related publication:
T. Kevin Best, C. Andrew Seelhoff, Jeffrey Wensman, Robert D. Gregg, "The Össur Power Knee with Phase-Based Control Provides Clinical Benefits over Passive Microprocessor Knees," Submitted to the Journal of NeuroEngineering and Rehabilitation, 2025.

Use and Access:
This data set is made available under a Attribution 4.0 International (CC BY 4.0) license.

To Cite Data:
Best, T.K., Seelhoff, C.A., Wensman, J., & Gregg, R.D. (2023). The Össur Power Knee with Phase-Based Control Provides Clinical Benefits over Passive Microprocessor Knees: Biomechanical Dataset. University of Michigan - Deep Blue Data. 

Trial Registration:
The experimental protocol was approved by the University of Michigan Institutional Review Board (HUM00230065) on February 9th, 2024. The trial is registered with the National Institutes of Health under ClinicalTrials.gov ID NCT06138977.