  Physics-based modeling and dynamic simulation of human eye movements has
significant implications for improving our understanding of the oculomotor
system and treating various visuomotor disorders. We introduce an open-source
biomechanical model of the human eye that can be used for kinematics and
dynamics analysis. This model is based on the passive pulley hypothesis,
constructed based on the data reported in literature regarding physiological
measurements of the human eye and made publicly available. The model is
implemented in OpenSim, which is an open-source framework for modeling and
simulation of musculoskeletal systems. The model incorporates an eye globe,
orbital suspension tissues and six extraocular muscles. The excitation and
activation patterns for a variety of targets can be calculated using the
proposed closed-loop fixation controller that drives the model to perform
saccadic movements in a forward dynamics manner. The controller minimizes the
error between the desired saccadic trajectory and the predicted movement.
Consequently, this model enables the investigation muscle activation patterns
during static fixation and analyze the dynamics of eye movements.
