Oscillatory Motion Lab Report

The two main components for walking and most mobile activities are the hips and the knees. The hip joint is a ball and socket joint, which means it can move in all directions. The knee joint is a compound condylar synovial joint and allows for flexion and extension of the leg. In this experiment the angle, angular velocity, and the angular acceleration of the knee and hip were analyzed in oscillatory motion. In the first set of experiments, the independent oscillation of the hip and knee were isolated and observed. Then the oscillation of these joints was viewed in conjunction while a subject walked, speed walked, ran, and walked on their tip toes.The periods for this experiment varied from 0.6s to 1.7s and the frequencies varied from 0.59Hz
First, the subject sat on an elevated surface and allowed their knee to oscillate freely. The period of this oscillation was 1.5s and the frequency was 0.67Hz. The amplitude of the angle was 0.3rad, the amplitude of the angular velocity was 1.8rad/s, and the amplitude of the angular acceleration was 9rad/s2 (Fig 2, Q1).
Then, the subject stood on an elevated surface and allowed their hip to oscillate freely. The period of this oscillation was 1.5s and the frequency was 0.67Hz. The amplitude of the angle for the hip was 0.25rad. The amplitude of the angular velocity of the hip was 1.25rad/s. The amplitude of the angular acceleration of the hip was 6.05rad/s2(Fig 3, Q1).
Next, the hip was allowed to oscillate freely while the knee was bent at approximately 90°. The period of this oscillation was 1.5s and the frequency was 0.67Hz. The amplitude of the angle for the hip was 0.65rad and the knee was 0.25rad. The amplitude of the angular velocity of the hip was 2.60rad/s and the knee was 1.30rad/s. The amplitude of the angular acceleration of the hip was 15.7rad/s2 and the knee was 9.9rad/s2(Fig 4,
The period for walking was 2.1s, 0.8s for speed walking and 0.6s for running. The data shows that as the subjects speed increases, the period’s frequency increases (Q4). For sitting and standing on an elevated surface the period was 1.5s and the frequency was 0.67 Hz. When the knee was locked at a 90° angle and the leg was allowed to freely oscillate the period was 1.5s and the frequency was 0.67 Hz. The period for walking was 2.1s with a frequency of 0.48 Hz (Q2). The angular acceleration and amplitude was greater than the angular velocity (Q2). The right and left hips are shown to be fairly symmetrical as shown in Figure 10 with the angles and oscillations being opposite each other (Q6). The discrepancy of the angles is due to the placement of the goniometers on either leg. Bending the knee shows no significant impact in the overall frequency of oscillations (Q3). The angle of forward rotation is equal and opposite the angle of backward rotation for hip movement (Q5). When comparing the normal walk and tip toe walk for the subject, the data shows a change in hip and knee angle. When the subject is walking normally the hip and knee angles are much larger than when walking on tiptoes (Q7 Fig 5, 9). Comparing data from different students the swing time and stride length vary greatly as shown in Figure 1. These results are expected because the height of each