An approach using photogrammetry and an ergonomic CAD system to evaluate mismatches between operational demands of agricultural tractors and physical and visional capabilities of youth drivers

The significance of young victims of tractor-related accidents has attracted the attention of epidemiologists and the public. Tractor operation depends on the operator's mental and physical capabilities; however, it is important to realize that exceptional mental capabilities do not compensate for the lack of physical capabilities and vice versa. This dissertation focuses on the evaluation of physical mismatches between operational demands and the operator's capabilities in tractor operations with respect to the reach, field of vision, and activation force.; The reach capabilities of youths on popular tractors were simulated based on the creation of digital human mockups using an anthropometry data set of US children. Visibilities for youths were simulated and compared with the visibilities for same-gender adults in order to display visual disadvantage of the youth operator. The overall evaluation for reach and visibility was simulated by an ergonomic CAD system in connection with photogrammetry software. The physical strengths of children were compared to the activation forces for various controls to verify their maneuvering capabilities.; Overall, the results suggest that there are differences between operational demands and the physical/visual capabilities of youth operators, which do not necessarily indicate the need for a ban on tractor operation by youth operators, but urge the necessity of awareness by supervisory adults and the public. Results of statistical analysis on the difference between physical capabilities and operational demands indicate that additional indicator can be used for the North American Guidelines for Children's Agricultural Tasks in accordance with the size demarcation of the tractor. The primary purpose of this dissertation is to confirm the difference between operational demands of agricultural tractors and the physical/visual capabilities of youth operators. Furthermore, it is expected that the confirmation of those differences will be used in related research and the development of guidelines; ultimately to contribute to decrease in agricultural injuries and deaths of children.