China 
Africa 
Explore chapters and articles related to this topic
Matrix Modeling of Joints and Links
Published in Ian S. Fischer, Dual-Number Methods in Kinematics, Statics and Dynamics, 2017
A plane joint features a plane surface on one link held in contact to form a bearing with a plane surface on another link so that three degrees of freedom are allowed. These freedoms are two translations on the surfaces of the bearing planes and a rotation about an axis perpendicular to the bearing planes.
Walking in high-heel shoes induces redistribution of joint power and work
Published in International Biomechanics, 2023
Harsh H. Buddhadev, David N. Suprak, Kamile H. Jordan, Angelo Hynds
Figure 1 shows ensemble average profiles for ankle, knee and hip sagittal plane joint angles, net joint moments and powers for barefoot and HHS walking conditions. Tables 1 and 2 summarize the peak net joint powers and work performed during the power phases, respectively. When walking in HHS, the participants generated less peak power and performed less positive work during late-stance ankle A2 push-off phase compared to barefoot walking. Conversely, the power generation and positive work performed at the early-stance knee K0 and mid-stance knee K2, and early-stance hip H1 and early swing hip H3 power phases were greater for HHS compared to barefoot walking. Similarly, power absorption and negative work performed during mid-stance hip H2 phases was also greater for HHS compared to barefoot walking. For the early to mid-stance ankle A1 power phase, less negative work was performed for HHS compared to barefoot walking. No difference in peak power absorption was observed during the early to mid-stance ankle A1 power phase between the experimental conditions. In addition, the power absorption and negative work performed during the early swing knee K3 and late swing knee K4 phases were not affected by the experimental conditions.
Patellofemoral joint kinetics in females when using different depths and loads during the barbell back squat
Published in European Journal of Sport Science, 2021
Linnea Zavala, Victoria Flores, Joshua A. Cotter, James Becker
Marker trajectories and ground reaction forces were exported to Visual 3D (C-Motion, Inc., Rockville, MD) where they were filtered using fourth order, zero-lag Butterworth filters with cutoff frequencies of 8 and 15 Hz, respectively, as determined by residual analysis. Joint angles were calculated using an XYZ Cardan rotation sequence corresponding to flexion/extension, ab/adduction, and internal/external rotation. Internal joint moments were calculated using Newton-Euler equations of motion and expressed in the proximal segment coordinate system. Sagittal plane joint angles and moments at the ankle, knee, and hip, were exported to a custom Matlab (Mathworks, Natick, MA) programme to calculate pfJRFs and pfJS. For kinematic descriptions of the squat positions, we determined the ankle, knee, and hip flexion angles at the deepest point for each depth.
What goes up must come down, part II: Consequences of jump strategy modification on dance leap landing biomechanics
Published in Journal of Sports Sciences, 2021
Danielle N. Jarvis, Susan M. Sigward, Katie Lerch, Kornelia Kulig
Data were exported from Visual 3D and analysed using custom MATLAB (Mathworks, Natick, MA, USA) code. The landing deceleration phase was defined from initial contact of the leading leg (vertical GRF > 20 N) through the maximum knee flexion angle during leading leg ground contact. Peak vertical and braking ground reaction forces during the landing deceleration phase were extracted. All net joint moments were normalized to body mass and expressed as internal moments, and peak sagittal plane net joint moments at the hip, knee, and ankle during landing were identified and extracted. In addition, sagittal plane joint angles at the hip, knee, and ankle at initial contact of landing and peak flexion during landing were extracted to quantify changes in the aesthetics of landing. The LECA, defined as the angle between the ground and a line connecting centre of pressure to the body’s centre of mass at initial contact of landing, was also calculated (Figure 1).