Control performance with three translational degrees of freedom

For multiple degree-of-freedom (DOF) systems, it is important to determine how accurately operators can control each DOF and what influence perceptual, information processing, and psychomotor components have on performance. Sixteen right-handed male students participated in 2 experiments: 1 involving positioning and 1 involving tracking with 3 translational DOFs. To separate perceptual and psychomotor effects, we used 2 control-display mappings that differed in the coupling of vertical and depth dimensions to the up-down and fore-aft control axes. We observed information processing effects in the positioning task: Initial error correction on the vertical dimension lagged in time behind the horizontal dimension. The depth dimension error correction lagged behind both, which was ascribed to the poorer perceptual information. We observed this perceptual effect also in the tracking experiment: Tracking error along the depth dimension was 3.8 times larger than along the other dimensions. Motor effects were also present, with tracking errors along the up-down axis of the hand controller being 1.1 times larger than along the fore-aft axis. These results indicate that all 3 components contribute to control performance. Actual applications of this research include interface design for remote control and virtual reality.