Two-Degree-of-Freedom Controller Design for Clutch Slip Control of Automatic Transmission

Optimal shifting control strategy in inertia phase of an automatic transmission for automotive applications

“…N is number of the friction pairs, r is the equivalent radius of the friction plate, P is clutch pressure, S p is the effective area of the friction plate, and F i0 represents the preload of the spring. The friction coefficient can be expressed as [9] μ c ¼ C 1 þC 2 e ð À 0:08ΔωÞ…”

“…Clutch-to-clutch shift control system for automatic transmission is designed to provide smooth transients for passenger comfort and better component durability [6,7]. It has many advantages over the conventional freewheeler bearing automatic transmissions such as simpler transmission designs and lower costs [8][9][10][11]. However, the clutchto-clutch transmission must maintain the same level of shift quality as conventional transmissions, which poses a challenge to transmission controller design.…”

Clutch slip control of automatic transmissions: A nonlinear feedforward-feedback design

“…Different from the optimal algorithms which use penalty functions to formulate multiple control objectives simultaneously, there is another kind of controller design method for clutch slip control, in which the only control objective is to make clutch speed track the reference trajectory. Especially for gear shift operation during driving, where the duration is much shorter than that of the start-up scenario, the speed tracking control method is widely used [1], [6], [9], [10].…”

A reduced-order nonlinear clutch pressure observer for automatic transmission using ISS

“…1, a planetary gear set is adopted as the shift gear, and two clutches are used as the actuators. In this study, two proportional pressure control valves are adopted to control equations of the 1st to 2 nd up shift inertia phase can be described by the following equation [8] Wt == C 11 T t + C 13 …”

“…Although in current production automatic transmissions, the clutch pressure is usually controlled by feed-forward control with gain-scheduling [3], some studies, such as [4], [5], [6], [7], [81, have tried to construct the model-based control law for clutch control. If state feedback is involved in clutch control systems [7], [8], the clutch cylinder pressure is necessary to be known for feedback control law. The sensors for measuring the clutch pressure, however, are seldom used because of the cost and durability.…”