Spatial stimulus–response (S-R) compatibility for foot controls with visual displays

This experiment examined the performance of 32 Chinese right-handed/right-footed participants for four spatial stimulus–response (S-R) mapping conditions with visual signals and foot controls in transverse and longitudinal orientations. The results showed that reaction times for the four S-R mappings were significantly different from each other. There was a significant interaction of visual signal position and response pedal key position which demonstrated the existence of a spatial S-R compatibility effect for this task. Compared to other non-correspondent S-R mappings, an improvement of 135 ms in reaction time was obtained with the correspondence of the stimulus and response key in both the transverse and longitudinal orientations. The findings suggested that the relative positions of visual signals and foot pedal response keys should be spatially compatible for the best human machine system performance. There was also evidence that spatial compatibility for the right–left dimension was stronger than for the front/rear dimension, and that responses with the right foot were faster than with left foot for the right-footed subjects used here.Relevance to industryMost of the previous studies on spatial S-R compatibility have been limited to the use of hand controls. The results of this study provide useful ergonomics guidelines for designing foot controls and visual displays, and this will be valuable for improving efficiency and performance in human–machine systems.