Digital ICD Control with Applications to Submarine Depth Control

Based on the ICD (Individual channel Design) approach, the design of a multivariable digital submarine depth control system is presented. The model of the submarine is the standard 80 meters British submarine. As expected, the frequency rate of sampling introduces limitations to achieve the required responses. Furthermore, the discrete model presents zeros close to imaginary axis resulting in a control system with bandwidths under the specified requirements. Nevertheless, it is found that the digital ICD, similar to it’s continuous counterpart, is a useful approach to analyse and design multivariable digital control systems in a transparent way, that is, in a way in which the limitations and possibilities to meet specifications can be elucidated prior to the design of any controller. In particular, the controller designed hereby was designed following a classical control approach. Key-Words: multivariable control, digital control, robustness, submarine applications