The docking process of the module was analyzed. When the uncertainty about control and geometry occurs, the basic geometric condition is analyzed to finish the docking action.

This method has several merits such as simple formula, clear physical conception, continuously controlled trap frequency that is independent on integral block number.

From the point of constraint control, this paper constructs a new multivariable self tuning regulator combining modular multivariable control technique and self tuning regulator.