Basic Motion Times ( BMT):
In this systems the times were derived from laboratory experiments and were carefully checked against a variety of factory operations before being accepted for general use. BMT data are based on basic motions. A basic motion occurs every time body member which is a rest moves and again comes to rest. For example teh action of knocking on a door requires two basic motions for every knock one to draw the hand back and another to move the hand forward and knock.