Simplify the following text for a Grade 11 native English-speaking person.
Original: Control engineering is the engineering field that focuses on mathematical modeling of systems of a various nature , analyzing their dynamic behavior , and using control theory to create a controller that will cause the systems to behave in a desired manner .
Simplified: Control engineering is the engineering discipline that focuses on the modeling of a diverse range of dynamic systems ( e.g. mechanical systems ) and the design of controllers that will cause these systems to behave in the desired manner .