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D. I. Stoia et al.
contact point. However, in order to develop control strategies in robotics, the angular
momentum should be computed about the total body center of mass (CoM) [5–7].
Respecting to CoM, the angular momentum during walking is conserved as long
as no external torque acts upon the body, according to Newton’s second law for
rotational motion. Angular momentum is composed of two quantities: rotational
angular momentum and translational angular momentum [8].
Rotational angular momentum (spin) reflects the angular momentum of a segment
computed about its center of mass [9]. Translational angular momentum (orbital)
represents the angular momentum of the center of mass of a segment about a chosen
point.
The kinematic data can be measured using motion analyzing systems [10–12],
while the body mass and inertia are computed based on ratios to the total body mass
[13].
Independently on the type of gait investigation (overground movement or on a
treadmill) [14, 15], the kinematical parameters are comparable.
The study reflects the measurements of kinematic gait parameters together with
calculus of masses and inertia of segments according to the existing literature and
aims to establish an analytic model for computing the total angular momentum of
the lower limb. The results, together with spatial and temporal parameters of gait
[16, 17], can be used in development of prediction systems for human locomotion
apparatus [18, 19].
2 Materials and Methods
2.1 Experimental Approach
The kinematic measurements have been measured in the Motion Analysis Laboratory
within Politehnica University of Timisoara. As the paper aims to establish a computational model, and not a statistical approach, only one healthy feminine subject was
involved in the study.
After a set of 10 min training, the subject has been equipped with ultrasound
markers which were placed on the tights and on top of the feet.
Prior to recording, the anatomical landmarks have been pointed. This pointing
serves to identifying the joints of the lower limb. The spatial coordinates of these
points are defined relatively to the tights and feet ultrasound markers.
The subject has accomplished three trials of walking, counting between 4 and 5
steps on each. The first trial was performed at a self-selected velocity of the subject,
followed by an increase of twice the velocity. After 3 trials at high velocity, the
subject was asked to walk with a decrease of half of the self-selected velocity.
The set of kinematical parameters corresponding to each walking velocity has
been exported for further data processing. The kinematic data recorded were: all
D. I. Stoia et al.
contact point. However, in order to develop control strategies in robotics, the angular
momentum should be computed about the total body center of mass (CoM) [5–7].
Respecting to CoM, the angular momentum during walking is conserved as long
as no external torque acts upon the body, according to Newton’s second law for
rotational motion. Angular momentum is composed of two quantities: rotational
angular momentum and translational angular momentum [8].
Rotational angular momentum (spin) reflects the angular momentum of a segment
computed about its center of mass [9]. Translational angular momentum (orbital)
represents the angular momentum of the center of mass of a segment about a chosen
point.
The kinematic data can be measured using motion analyzing systems [10–12],
while the body mass and inertia are computed based on ratios to the total body mass
[13].
Independently on the type of gait investigation (overground movement or on a
treadmill) [14, 15], the kinematical parameters are comparable.
The study reflects the measurements of kinematic gait parameters together with
calculus of masses and inertia of segments according to the existing literature and
aims to establish an analytic model for computing the total angular momentum of
the lower limb. The results, together with spatial and temporal parameters of gait
[16, 17], can be used in development of prediction systems for human locomotion
apparatus [18, 19].
2 Materials and Methods
2.1 Experimental Approach
The kinematic measurements have been measured in the Motion Analysis Laboratory
within Politehnica University of Timisoara. As the paper aims to establish a computational model, and not a statistical approach, only one healthy feminine subject was
involved in the study.
After a set of 10 min training, the subject has been equipped with ultrasound
markers which were placed on the tights and on top of the feet.
Prior to recording, the anatomical landmarks have been pointed. This pointing
serves to identifying the joints of the lower limb. The spatial coordinates of these
points are defined relatively to the tights and feet ultrasound markers.
The subject has accomplished three trials of walking, counting between 4 and 5
steps on each. The first trial was performed at a self-selected velocity of the subject,
followed by an increase of twice the velocity. After 3 trials at high velocity, the
subject was asked to walk with a decrease of half of the self-selected velocity.
The set of kinematical parameters corresponding to each walking velocity has
been exported for further data processing. The kinematic data recorded were: all