# Quasi-Static Simulation

Physically, quasi-static means that the system is being driven extremely slowly so as not to engage any transient dynamics. Mathematically, quasi-static simulation is a sequence of static simulations performed over a given duration. It is useful when your model contains time-dependent forces or motions and you are interested in the sequence of equilibrium configurations your model passes through.

For the first time step, the model configuration is taken as a starting point, then the Force Imbalance method is used to compute the equilibrium, such that there are no unbalanced forces or torques on any of the bodies in the system, and all the kinematic constraints are satisfied. This configuration then becomes the starting point for the next time step, and so on.

The step size provided by the user is adhered to by the solver. Too large of a step size may cause convergence difficulties. For a detailed description of all the parameters used to control this simulation, please refer to MotionSolve Reference Guide.