Automated Manual Transmissions - A European Survey and Proposed Quality Shift Metrics Ricardo plc

Format:

Conference/Event

Author/Creator:

Wheals, J. C., author.

Conference Name:

SAE 2002 World Congress & Exhibition (2002-03-04 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2002

Summary:

In Europe there is considerable growth in the application of automated manual transmissions (AMT) predominantly for reasons of cost and CO2 efficiency. It is believed that restricted functionality and the poor shift quality of this "first wave" of manual-based transmissions may hinder this trend being repeated in markets dominated by conventional automatic transmissions (ATs) such as the USA.This paper addresses two areas:Data is presented from a wider survey of current production "robotised" manual transmissions sold in the European market. This study included vehicles from B, C, and D/E classes and the light truck sector. The transmissions featured a single dry clutch, single layshaft and either electrical or electro-hydraulic actuation of the clutch and the shift rails. Universally, it was found that shift quality was poor in comparison to conventional ATs by at least 1.5 points on a 1-10 rating scale, as assessed by a panel of experienced transmission calibrators. The paper discusses the powertrain factors contributing to this difference and how the shift quality could be improved prior to the next generation of manual-based transmissions, namely twin clutch designs (AMT-2).Initial research is presented for shift quality metrics to allow prediction of subjective ratings from objective measures. Novel techniques are discussed to improve the correlation between engineering parameters and subjective ratings:

Notes:

Vendor supplied data

Publisher Number:

2002-01-0929

Access Restriction:

Restricted for use by site license