Comments on the engine control problem

Today the automobile industry is facing unprecedented technical challenges in its attempts to meet the severe and conflicting demands of improved fuel economy and exhaust emission performance. Part of the solution to these problems resides in developing improved engine controls for such variables as air-fuel ratio, ignition timing, and exhaust gas recirculation. This paper defines the engine control problem in terms familiar to control systems specialists and suggests the structure of a solution. This problem is quite complex and at worst is nonlinear, time varying, and stochastic as well as involving multiple input and output variables. In view of the above factors, as well as the fundamental trade-off between fuel and exhaust emissions, and environmental and system parameter variations, the use of closed loop optimal and/or adaptive controllers is proposed. Improved sensor and actuator technology as well as adequate mathematical models are necessary to produce a solution of this difficult control problem.