A mechatronic study on a self-energizing clutch actuator system: modeling, estimation, and control

Abstract

In many engineering fields, newly designed actuators using novel drive principle in conjunction with the advances in mechatronic technologies have been researched and developed to improve conventional systems. They are considered in terms of integrating system design in aspect of control performance as well as the mechanical design aspect. Such an approach is also taken into consideration to automotive subsystems. The development of a new actuator structure driven by an electromechanical device with a dry clutch is required to reduce the production cost. However, most of clutch-related applications are based on a conventional dry-clutch system for manual transmissions. The negative effect originated from nonlinear characteristics caused by preload in a diaphragm spring is unavoidable.

The new clutch actuator has self-energizing mechanism to amplify the normal force applied on the contact surfaces for the engagement. This self-energizing clutch actuator (SECA) system allows the clutch module to consume less amount of energy for actuating the overall system. The bevel gear set is employed to implement a self-energizing mechanism for rotating apparatus. The equations of motion of the clutch-mechanism are represented to capture the essential dynamics of the proposed system. A model-based actuator position tracking controller is developed for the engagement of the clutch. Also, passivity analysis of the actuator system provides a design guide to prevent the clutch from being stuck. Finally, torque transmissibility based on the self-energizing effect is validated experimentally.

In addition to the system model based on the manipulator dynamics, the nonsmooth model is developed to describe the contact transition effect. This effect is needed to be considered because the proposed system has high stiffness due to the self-energizing mechanism. The model is reconsidered as an application of mechanical systems with unilateral constraints. The framework of nonsmoo...