The Study on Clutch Shift Control Based on Sliding-Mode

Abstract

This paper has presented a systematic approach for the pressure-based clutch fill and engagement control of wet clutches in automatic, dual clutch, or hybrid transmissions. The clutch fill and engagement controls have been critical for the clutch-to-clutch shift technology, which is the key enabler for fuel-efficient, compact, and low-cost transmission designs. The main challenges of the pressure-based clutch control design lie in the complex dynamics, the ON/OFF behavior during the clutch fill phase, the pressure chattering effect induced by inappropriate control gain design, and the precise pressure –tracking requirement during the dynamic loading condition transient. To address these challenges, first, a dynamic model capturing the bulk modulus variation and the piston motion wiggling effect has been constructed based on extensive experimental results.