2 nd International and 17 th National Conference on Machines and Mechanisms iNaCoMM2015-050 ________________ Sivakumar Ramalingam Ashok Leyland Ltd, Technical Centre, Chennai, sivakumar.r@ashokleyland.com Sanjeev Ramakant Pimpale Ashok Leyland Ltd, Bhandara Plant, Nagpur, pimpale.sr@ashokleyland.com Srinivasa Prakash Regalla Department of Mechanical Engineering, BITS, Pilani (Hyderabad), regalla@hyderabad.bits-pilani.ac.in 1 Modelling of a Prognostics Observer for Automated Manual Transmission Sivakumar Ramalingam, Sanjeev Ramakant Pimpale, Srinivasa Prakash Regalla Abstract Currently gear actuation control of Automated Manual Transmission (AMT) does not receive the feedback on the actual condition of the gearbox hardware, particularly synchronizer which is critical for gear shift quality. This paper covers modelling of a Prognostics Observer for AMT system. The observer captures the real time position of the gear shift actuator, specifically during synchronization phase of the gear shift cycle. Based on the travel measured at the gear actuator end, synchroniser wear is estimated. Also, the synchronization time is continuously monitored and warning for re-calibration of the AMT system is provided when the synchronization time goes beyond the allowable limits. Condition monitoring provides the prognostic functionality for AMT system using ensures consistent gear shift quality, desired vehicle driveability and warning for repair and/or re-calibration. Also, systematic analysis of the monitored data provides an accurate diagnosis of a developing fault. Thus, with the advanced control systems in place for AMT, it is possible to develop a closed loop feedback based condition monitoring system for improved diagnostics and prognostics of AMT system. Keywords: Automated Manual Transmission, AMT, Prognostics, Diagnostics, Observer, Condition Monitoring, Gear Shift Quality. 1 Introduction Automated Manual Transmission (AMT) is an advanced “Shift by wire” technology which is integrated on a conventional manual transmission (MT). An AMT system consist of a dry clutch, a base gearbox (same as MT), and an embedded dedicated transmission control system that uses electronic sensors, processors, and actuators to actuate clutch & gear shifts. It operates similar to a manual transmission except that it does not require clutch actuation or gear shifting by the driver. No clutch pedal is present and the gear shift lever is replaced by a joystick (only forward or reverse gear is selected by the driver). AMT is almost two decade old technology and developed countries have migrated to advanced technologies like DCT. Electronic controlled engine (required for meeting stringent emission norms – BS4 & above) is a pre-requisite of AMT system as well. Hence, latest emission legislation in India has made AMT commercially feasible. Functional block diagram of a typical AMT System is as shown in Fig. (1). A fully automatic (AT) transmission deploys prognostics by fusing a degradation model with the pre-lockup feature from measurement, under the extended Kalman filtering framework [1].