Activities Based on the Shuttlecock Data for Subject Paul
Motion and force data were taken for subject Paul as he served a shuttlecock in the xdirection at the Chapin Gait Analysis Center. The data are in an Excel spreadsheet file,
PaulShuttlecock2AA.xls. A video and an animation of his motion are also available.
The video is in the file Paulshuttlecock2.mpg. A stick figure animation showing
recorded force vectors is in the file PaulShuttlecock.mov.
Conceptual Activity:
1. Use the graphical capability of Excel to draw x-position versus time graphs for the
five markers that are attached to the badminton racket and the shuttlecock. Which
marker is on the shuttlecock? Justify your answer.
2. Observe the animation PaulShuttlecock.mov. Compare the motion of his serving
hand to the motion of the badminton racket head.
3. Observe the animation PaulShuttlecock.mov. As Paul steps forward to serve his
weight shifts to another force plate. The animation shows the net force vector.
Describe what happens to the direction and magnitude of the force vector as a step is
taken.
5. Describe the direction changes of the force vector on the foot during the time of a
step. Explain those changes.
6. Make a graph of the x-coordinate versus time for the Top Head (X1) and the Right
Heel (X18). Does the head move for the entire time period? Does the heel move for the
entire time period?
7. Make a graph of the z-component of force versus time for force plates 2-abd 3.
Describe the shape of this component over the course of a step. How does this shape
correlate with what is happening to the heel and toe during a step?
Analytical Activities:
1. Develop a spreadsheet that can estimate instantaneous velocity from the position
data for the right wrist and the first four markers on the badminton racket. During
which time period and which part of the serving acitivity are the speeds the greatest?
Explain your answer.
2. Use the velocity spreadsheet to compare velocities of the Top Head, wrist, and heel.
Write an essay describing the comparison. You might address questions such as
whether any of these parts ever stop during a steady walk.
3. What is the maximum downward force exerted by each foot on the plate as it strikes
the floor? What is the maximum upward force exerted on each foot by the plate as the
foot lifts from the floor?
4. Using Excel’s chart wizard, make a graph of the motion of the sensor attached to
Paul’s right wrist versus time. Compare this to the graph of the motion of the sensor
attached to Paul’s right elbow versus time. What can you say about Paul’s arm motion
during the run?
5. Make a graph of the motion of the sensor attached to the right side of his head versus
time. Compare this graph to the motion of the sensor attached to the right shoulder.
Synthetical Activities:
1. Look carefully at the vertical (z) component of force during a step. How does the
magnitude compare when the heel is in contact with the floor and when the toe is in
contact?
2. By observing the animation file PaulShuttlecock.mov you can recognize that the force
plate is measuring the force on one foot. By using this knowledge of the force on one
foot, develop an estimate of the total vertical force on Paul as a function of time.
3 Develop an estimate of the total horizontal force on Paul as a function of time.
4. Develop a spreadsheet that can estimate the position of the center of mass of each
body part described in the file HumanAnthropomorphicData.doc.
5. Assume that Marker 5 represents the motion of an object through a fluid. Use the
given data to develop a mathematical model for the drag force acting on Marker 5 as it
travels through the fluid. What is the time period for the motion of Marker 5 through
the fluid? Explain your answer. Estimate the vertical acceleration of Marker 5. How
does it change in time?