Comparison of kinematic and kinetic methods for computing the vertical motion of the body center of mass during walking

Compliant leg behaviour explains basic dynamics of walking and running

“…The horizontal GRF shows the observed change from negative to positive values and the vertical axis, the double peak that distinguishes the walking gait (F x and F y , first row of subplots). Correspondingly, as in animals and humans (Lee & Farley 1998;Gard et al 2004), the COM oscillates around its landing height in the vertical GRF with a smaller increase in height during stance than that of the inverted pendulum motion (Dy, second row). Moreover, closer than the inverted pendulum, the bipedal springmass model describes the out-of-phase changes in the forward kinetic and the gravitational potential energies that occur in walking (DE k,x and DE p , third row).…”

Level walking in adults with and without Developmental Coordination Disorder: An analysis of movement variability

“…In this study we used one of the simplest kinematic methods, a single marker placed on the sacrum, to approximate CoM motion. This single marker method has been shown to be an effective, inexpensive, and reasonably accurate estimate in the vertical direction at slower walking speeds (Gard, Miff, & Kuo, 2004;Saini, Kerrigan, Thirunarayan, & Duff-Raffaele, 1998;Thirunarayan, Kerrigan, Rabuffetti, Croce, & Saini, 1996), as well as in the medio-lateral and frontal direction to analyze simple movement activities without trunk flexion or limb bending (Mapelli et al, 2014). For each step sacral root mean squared velocity (ms -1 ) and acceleration (ms -2 ) was calculated over the three axes of movement:…”

ZeroG: Overground gait and balance training system

“…We programmed the linear actuator to move up and down through a sinusoidal pattern with a peak-to-peak amplitude of 5 cm. Such a movement trajectory is representative of a person's COM movement while walking at approximately 1.4 m/s [16]. We programmed the linear actuator to move at frequencies of 0, 0.5, 1.0, and 1.5 Hz, while the magnitude of unloading was set to 10, 25, 50, 75, and 100 lb, respectively.…”

“…In this setting, as the patient moves up and down, they experience a constant amount of vertical support, which can be set as a percentage of the patient's body weight. Dynamic BWS has been shown to produce more natural ground-reaction forces and gait characteristics [11][12][13][14][15][16][17][18] and allows patients to move freely through a wide range of movement profiles (e.g., those needed during gait, sit-to-stand, and getting off the floor). Such activities are not possible with static BWS systems, yet are critical to a patient's ability to practice activities of daily living (ADLs).…”