The Control of nonlinear dynamic systems is a widely recognised challenging issue. The key point in non-linear
control system design is a general model prototype with conciseness, flexibility and manipulability while keeping little loss
of precision, which is the insight and origin of U-model developed. Sine the U-model is proposed, a new research area
has been opened for the nonlinear control system design. This paper surveys the major progression on the nonlinear plant
identification, the control system design and the robustness within the U-model domain, and also proposes the possible
expansion for the future research work.