Dual Clutch Transmissions (DCT) have revolutionised driveline technology, providing automatic transmission operation with excellent shift quality, producing dynamic operation and driving comfort together with high efficiency, resulting in low fuel consumption and CO_2 emissions. Given the benefits, DCTs have an expanding if still a somewhat limited range of market applications, due to primarily high unit cost and increasing package and weight for higher ratio spreads. Ricardo has developed a number of alternative DCT architectures and concepts, which address certain key constraints and enable expansion of DCT technology into both conventional and alternative market sectors. In this paper the latest developments in three new DCT technology families will be presented: 1. Manual DCT: Ricardo has developed a cost reduced DCT concept utilising conventional mechanical systems, simplified clutches and simple hydraulics with no need for electronic control systems. This provides the driveability benefits of a DCT in a highly simplified transmission. Shifting is via manual application. Hardware has initially been developed for utility and farm vehicles with additional applications to a range of market sectors from motorcycles to entry level automotive vehicles through to high torque capacity on- and off-highway vehicles. 2. HiTorque DCT10 for high performance vehicles and light commercial trucks: The configuration offers torque capacities of 950Nm with high gear ratio spreads and next generation high pressure actuation technology yielding a power loss signature of a dry clutch DCT equivalent. The architecture family offers also 8, 9, 10 and 12 speed variants, allowing modification for desired ratio variation. 3. MCA - Mono Clutch Automatic: It also needs to be considered whether there is an intermediate step - retaining the functionality of a DCT but with the price competitiveness of an automated manual transmission (AMT). Previously, the AMT has been rejected in some markets due to poor shift quality. However, the latest Ricardo ideas show that there are technical solutions to this conundrum. It has been found possible to have DCT functionality at AMT cost and that such a transmission will have characteristics acceptable to large parts of the passenger car and commercial vehicle market sectors.
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