Development of the electromagnetic shift unit for commercial vehicle (Improvement of the controllability to applying the EEC, and optimization of the control parameters by using the Taguchi method)

Abstract

Automated Manual Transmission (AMT) is adapted to commercial trucks as high efficiency automatic transmission. In this paper, we describe a result of control experiment of electromagnetic actuator developed for AMT's shift unit. There is a drawback that the electromagnetic shift unit has low controllability since there is large response delay of the electromagnet current to the voltage. It is considered that the low controllability is due to the fact that the inductance of the electromagnet is so large that it can't be ignored, and it changes depending on applied current and control positions. Therefor the shift unit has a problem that it can't stop at the target gear in position and the large noise occurs when it hit the stroke stopper. In order to improve the controllability of the shift unit, PID control, sliding mode control (SMC), and energy evaluation control (EEC) are applied to the control of the shift unit. EEC is a new control rule that we proposed and this control rule is based on the bang-bang control theory. Each control parameters of PID, SMC, EEC was set to 3 parameters and Taguchi method was used for optimization of these parameters. As a result of the experiments, it is found that the EEC is most suitable for the control of the shift unit. Validity and usefulness of the EEC are confirmed from this result.

Keywords

• electromagnet
• shift unit
• energy evaluation control
• slidingmode control
• tauchi method