Using design features as visual cues to support mental rotation activities in manual assembly operations

This research study investigated how an individual\u27s mental rotation ability can affect his or her performance in manual assembly operations and whether different kinds of work instructions can enhance an individual\u27s mental rotation activities during the course. The study also examined the fitness of a proposed cognitive model for manual assembly operations and the effectiveness of resulting work instructions. The participants were asked to perform assembly tasks of a one-cylinder, four-cycle small engine according to the work instruction provided. The work instruction treatment consisted of product assembly information in the form of an exploded diagram, step-by-step procedures, or an animated video. Through the participant following the on screen work instructions and assembling three dimensional parts in a computer simulation environment, the tactile information through contacting the product was reduced to the minimum and thus the performing of mental rotation activities was enforced. The experiment design for this study was a two-by-three factorial design, where there are two levels of individual mental rotation ability and three levels of treatments. Vandenburg\u27s Mental Rotation Test was used as a pretest instrument to differentiate the participants\u27 spatial ability. A treatment of work instructions then was assigned randomly to each participant to assemble the given products accordingly. The performance of participants was measured through a compounded Performance Index; both the speed and accuracy were measured. Participants in the study were undergraduate students from several academic majors in the engineering and technology fields and primarily first and second year student. Results of the study showed main effects and interaction between two independent variables. Nevertheless, only the performance difference between two MRT groups was significant. There was no evidence of significant performance difference between different work instruction treatment groups. Less than one third of participants favored the work instructions provided, which might directly affect the learning outcomes of the remaining participants. More participants preferred having step-by-step procedural work instructions than the other two; around one third of participants preferred a combination of all three presentation strategies