Measurement of Friction Coefficient on a Powder Layer and Fluid Dynamic Study

Major results 6: The sliding position of a disk

In order to obtain the slope of a disk sliding, the distance between the base of the disk and the track-board surface was measured with a laser displacement sensor set over the board at intervals of 0.2 milliseconds during sliding. As an example, one result was plotted in Fig. 15. Points from about 30 milliseconds to about 65 milliseconds show a plateau of a disk top from a track board surface. In every results, the front of a disk was higher than the rear.

Fig. 15. The distance between the top of the disk and a surface of the track board. The plotted points are obtained from data of the laser displacement sensor.

In the list of conditions and results of experiments, the slide runs for which slope of disk was obtained are indicated by symbol ·. Click on the dot to see the graph of  the distance between the base of the disk and the track-board surface which is calculated from the obtained distance between the sensor and the top of the disk for simplicity. The velocity of the disk at measurement and the deviation of the center of the disk and a point of measurement are also shown.

However the value for the distance between the track board and the base of the disk is not the absolute distance, since the position of the sensor shifted during measurement in some cases.

Measurement of Friction Coefficient on a Powder Layer and Fluid Dynamic Study