Kinematical theory of human sequential movements

Sequential movements characterized by the partially-defined states of dynamical systems are discussed. A kinematical model for the control of human sequential movements is formulated by establishing three axioms. The first axiom reflects the minimum-jerk model for simple point-to-point movements. For more complicated movements, the predicted trajectory based on the minimum-jerk model differs from the observed trajectory. The second constructive axiom requires that the observed trajectory of the movements coincides with the modified trajectory based on that calculating from the minimum-jerk model. The third additional axiom predicts that the movement for unskilled tasks is segmented. The constructive model presented here predicts the measured trajectories in planar, multijoint arm movements. The optimization approach is critically discussed on the basis of the present axiomatic study on sequential movements.