Abstract
This paper addresses a gear shift scheduling of an automatic transmission that is one of major key factors on fuel economy and performance of a motor vehicle. A new gear shift schedule generation method which enables to optimize the fuel economy is proposed. The method is based on direct projection of an engine specific fuel consumption map on a driver demanded power map. The shift schedule can be derived from the specific fuel consumption property of an engine directly. Furthermore, an extended algorism to consider the constraints of various driving conditions is studied. A method to evaluate a gear shift schedule is introduced to compare the proposed method with a conventional method. The proposed method is useful for a parameter study in early stage of vehicle development, and has an advantage to conventional method based on a gear shift scheduling Finally, improved fuel economy with the method is demonstrated in emission test cycle simulations.
