Lower-limb kinematics and kinetics during continuously varying human locomotion

Abstract

Human locomotion involves continuously variable activities including walking, running, and stair climbing over a range of speeds and inclinations as well as sit-stand, walk-run, and walk-stairs transitions. Understanding the kinematics and kinetics of the lower limbs during continuously varying locomotion is fundamental to developing robotic prostheses and exoskeletons that assist in community ambulation. However, available datasets on human locomotion neglect transitions between activities and/or continuous variations in speed and inclination during these activities. This data paper reports a new dataset that includes the lower-limb kinematics and kinetics of ten able-bodied participants walking at multiple inclines (±0°; 5° and 10°) and speeds (0.8 m/s; 1 m/s; 1.2 m/s), running at multiple speeds (1.8 m/s; 2 m/s; 2.2 m/s and 2.4 m/s), walking and running with constant acceleration (±0.2; 0.5), and stair ascent/descent with multiple stair inclines (20°; 25°; 30° and 35°). This dataset also includes sit-stand transitions, walk-run transitions, and walk-stairs transitions. Data were recorded by a Vicon motion capture system and, for applicable tasks, a Bertec instrumented treadmill.

Fig. 1

Locomotion modes and practical transitions (T1 through T3) considered in this study. ‘Walk’ and ‘Run’ occur on a flat surface, whereas ‘Stairs’ occurs on a staircase. All modes except ‘Sit’ are continuously parameterized by speed and inclination, which are sampled in the dataset. Note a sit-stand transition corresponds to T₁ with zero gait speed in ‘Walk’.

Fig. 2

Marker Set: Markers were placed on left and right limbs symmetrically, left side markers shown. Markers noted with a ‘*’ are used in the conventional gait model. For full description of marker locations, see Nexus 2 user guide.

Fig. 3

Inter-participant average walking kinematics and kinetics for all inclines at 1.0. Inclines reported in degrees. Foot contact corresponds to 0 of the gait cycle. Solid lines and shaded regions represent the average trajectory and its variation within one standard deviation, respectively. Positive or negative normalized power denotes generation (Gen.) or absorption (Abs.) of mechanical power, respectively. These plots correspond to Walk in Normalized.mat, as detailed in the README.

Fig. 4

Inter-participant average running kinematics and kinetics at all speeds. Foot contact corresponds to 0 of the gait cycle. Solid lines and shaded regions represent the average trajectory and its variation within one standard deviation, respectively. Positive or negative normalized power denotes generation (Gen.) or absorption (Abs.) of mechanical power, respectively. These plots correspond to Run in Normalized.mat, as detailed in the README.

Fig. 5

Inter-participant average sit-to-stand kinematics. Solid lines and shaded regions represent the average trajectory and its variation within one standard deviation, respectively. These plots correspond to SitStand in Normalized.mat, as detailed in the README.

Fig. 6

Stair ascent steady-state and transition kinematics. Inter-participant average kinematics for steady-state stair ascent and the transitions walk-to-stair-ascent and stair-ascent-to-walk. Stride 3 is plotted for the steady-state case because it is the most periodic stride. Stair inclines are reported in degrees. Solid lines and shaded regions represent the average trajectory and its variation within one standard deviation, respectively. These columns respectively correspond to the ascent cases of w2s, s3, and s2w under Stair in Normalized.mat, as detailed in the README.

Fig. 7

Stair descent steady-state and transition kinematics. Inter-participant average kinematics for steady-state stair descent and the transitions walk-to-stair-descent and stair-descent-to-walk. Stride 3 is plotted for the steady-state case because it is the most periodic stride. Stair inclines are reported in degrees. Solid lines and shaded regions represent the average trajectory and its variation within one standard deviation, respectively. These columns respectively correspond to the descent cases of w2s, s3, and s2w under Stair in Normalized.mat, as detailed in the README.