Data format:

------------

Each line contains 19 columns:

Column      1:   Time (in seconds)

Columns   2-9:   Vertical ground reaction force (VGRF, in Newton) on each of 8

          sensors located under the left foot

Columns 10-17:   VGRF on each of the 8 sensors located under the right foot

Column     18:   Total force under the left foot

Column     19:   Total force under the right foot.

When a person is comfortably standing with both legs parallel to each

other, sensor locations inside the insole can be described (according

to the Infotronic website; http://www.infotronic.nl/) as lying

approximately at the following (X,Y) coordinates, assuming that the

origin (0,0) is just between the legs and the person is facing towards

the positive side of the Y axis:

Sensor       X      Y

----------------------------

L1         -500   -800

L2         -700   -400

L3         -300   -400

L4         -700      0

L5         -300      0

L6         -700    400

L7         -300    400

L8         -500    800

R1          500   -800

R2          700   -400

R3          300   -400

R4          700      0

R5          300      0

R6          700    400

R7          300    400

R8          500    800

The X and Y numbers are in an arbitrary coordinate system reflecting

the relative (arbitrarily scaled) positions of the sensors within each

insole. During walking, the sensors inside each insole remain at the

same relative position, but the two feet are no longer parallel to

each other. Thus, this coordinate system enables a calculation of a

proxy for the location of the center of pressure (COP) under each

foot.

Data file names:

----------------

These follow a common convention, e.g., GaCo01_02.txt  or  JuPt03_06.txt,

where

Ga, Ju or Si – indicate the study from which the data originated:

    Ga - Galit Yogev et al (dual tasking in PD; Eur J Neuro, 2005)

    Ju – Hausdorff et al (RAS in PD; Eur J Neuro, 2007)

    Si - Silvi Frenkel-Toledo et al (Treadmill walking in PD; Mov Disorders,

          2005)

Co or Pt: Control subject or a PD Patient

01: Subject number in the group

A walk number of 10  (for the "Ga" study) indicates a dual-task walking,

where the subject was engaged in serial-7 subtraction while walking.

A walk number of 01 refers to a usual, normal walk. 

.txt: file name extension

The sampling rate was 100 Hz.