Book Description

"The speed and accuracy of positioning movements as functions of distance, direction, and mass were investigated under simulated weightless conditions. Subjects seated on a frictionless device made blind positioning movements by sliding each of two frictionless masses (1000 or 7000 grams) various distances (10, 20, and 40 cm) either left-to-right or near-to-far. Both speed and accuracy decrease with distance; left-to-right movements take longer, but are more accurate than near-to-far movements. Speed decreases with increased mass. With minor exceptions, the effects are similar to those noted when fixed subjects position weightless objects. The responses of fixed subjects were slower, but more accurate, and were not affected by the variable of mass."--Abstract.