Towards Bridging the Gap between Biomechanics and Motor Control for Virtual Ergonomics Applications

Posture prediction algorithms, particularly those that consider comfort (or discomfort), are typically based on gross movements rather than on the finer movements of the upper extremity. However, understanding these finer movements, particularly during goal-directed reaching tasks, is critical to accurately predicting postures, and the associated potential injury risks, when using virtual ergonomic tools. Furthermore, it is expected that these finer movements will be highly sensitive to the planning processes used to perform sequential tasks, particularly when start and terminal orientation, terminal precision, and terminal force are manipulated. Thus, the purpose of this proposed study is to challenge the theory of the end-state comfort effect under conditions of varying terminal precision and exertion force requirements during both discrete and sequential goal-directed reaching tasks. It is expected that each of these manipulations (i.e. start and terminal orientation, terminal precision, terminal force, and number of movement sequences) will influence the chosen movement patterns. Understanding how each of these variables affects movement patterns will provide important information for the development of posture prediction algorithms for use with virtual ergonomics tools.