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6-Speed PowerShift automatic in Fiesta, Focus delivers a 10% fuel economy gain

The new dual dry-clutch Ford PowerShift six-speed automatic available in the Focus and Fiesta enables a 10% fuel economy gain compared to a four-speed automatic transmission, contributing to both cars delivering as much as 40 mpg on the highway. The PowerShift automatic consists of two manual transmissions (in the same case) working in parallel. Each has its own independent clutch unit controlled by computers and fast-acting electromechanical actuators that shift the gears.

One clutch carries the odd gears, 1, 3 and 5, while the other carries the even gears, 2, 4 and 6, and reverse. PowerShift is an automatic because the gear changes are coordinated by a computer that directs the clutches to engage and disengage in a way that provides seamless delivery of torque to the wheels, even during gear changes. Ford PowerShift’s features include:

  • Torque Hole Fill: A Ford-developed and patented innovation that eliminates the slight hesitation drivers feel during acceleration when the transmission upshifts into a higher gear.

  • Hill Start Assist: If sensors detect the Fiesta or Focus on a slope of 5 degrees or more, Hill Start Assist automatically prevents the car from rolling backward in the instant when the driver moves his or her foot from the brake to the accelerator. PowerShift’s computer controls the brake pressure and engine to hold the car in place.

  • Neutral idle: This feature helps improve fuel economy by eliminating the drag a traditional hydraulic transmission puts on the engine when a vehicle is idling.

  • Reduced weight: PowerShift weighs nearly 30 pounds less than the four-speed automatic transmission in the 2011 Focus. Less weight helps improve fuel economy.

Ford engineers began developing the dual-clutch technology when advances in the speed of processors, memory and the mechanical actuators that shift the gears progressed to the point that a manual transmission could be made to perform as smoothly as an automatic.

The kind of computing power needed in terms of speed and amount of memory advanced to the point where it is now possible to offer the driver fast, crisp and seamless shifts from this advanced transmission at an affordable price.

—George Herr, PowerShift calibration supervisor

Since its launch in Fiesta in 2010, Ford engineers have continued to develop and refine PowerShift’s performance and efficiency. The PowerShift for the all-new Focus, for example, offers several new features including a more compliant clutch damper spring design to reduce noise levels. Piero Aversa, PowerShift engineering manager, said the Focus shift schedule has been optimized for the wider torque band provided by the car’s 160-horsepower, direct-injected 2.0-liter engine.

Also new for Focus is the SelectShift Automatic feature. SelectShift allows a driver to change gears—up or down—by pressing a button on the shift handle. By pushing the plus sign button, the transmission upshifts. Push the minus sign button and the car downshifts. The PowerShift computer prevents a driver from downshifting too fast and causing damage from over-revving. In the Focus, drivers also can choose Sport Mode, which changes the timing of the shifts for quicker acceleration.

Ford engineers also worked to improve low-speed responsiveness and smoothness in response to customer feedback.

Comments

HarveyD

What an easy way to lower fuel consumption. It is difficult to accept that this was not done 50 or even 60 years ago.

Mannstein

Computer chips weren't around 50 or 60 years ago with the level of integration and cost required.

yoatmon

@ HarveyD:
Evolution takes place over time. There is principally no difference between natural and technical evolution as far as the factor time is concerned.
Additonally, there was not as much pressure for innovative solutions 50 years ago as presently.

SJC

When gasoline is cheap you do not need all the innovations. Necessity is the mother of invention.

HarveyD

Who decides what we are driving? It is a very pertinent question.

I guess that adding one extra gear every 10 to 15 years may be the best those people are prepared to do. Others are producing 8 gear transmission already.

The electronics required could have been made 50 years ago (or at the same time we went to the moon) and upgraded many times thereafter.

There are no acceptable reasons why it was not done.

Nick Lyons

@HarveyD:

There are no acceptable reasons why it was not done.

Acceptable to whom? The auto manufacturers and oil companies found gas guzzlers to be perfectly acceptable.

As others have pointed out, cheap gasoline meant there was little demand for such an innovation 50 years ago. Just putting an extra, taller gear into all transmissions back then would have saved a lot of gas over the years, but in a competitive marketplace where some costs are externalized or deferred, auto makers were not motivated to do it. Free markets are dynamic and help create a lot of wealth, but completely unfettered markets don't always provide the best outcomes in the long term. There is a place for regulation in the marketplace, providing a seat at the table for consideration of the common good and that of future generations. 50 years ago the only 'regulation' in this space was being done by big oil and big auto, and no one with the ability to change product direction was looking past next quarter's results.

Duncan

I have been using a very similar system for many decades...it's called a manual transmission! Anyone who cannot master a stick shift and clutch should not be allow to drive a car, unless they have a physical disability.

Brian P

Automatic in the form of "automated-manual" transmissions have been around for a long time, but the innovation of using two clutches to control alternating gears to enable smooth gear changes has not, and the computing power to co-ordinate which gear to pre-select and to co-ordinate disengaging one clutch and engaging another has most certainly NOT been around "50 years ago" and to even suggest that is an absurdity. Computers back then were the size of a house and cost a fortune.

Could it have been done without such computing power available? In some sort of fashion ... sure. But without the benefit of a torque converter to smooth out gear changes and without very careful control of the mechanical clutches, and without control of engine load while changing gears (requires drive-by-wire), it would have been a very jerky experience that almost no ordinary people would have considered acceptable. Actually, there is an example of such a transmission available right now, in the Smart car. Go drive one and come back and tell us what most people think of the transmission in those. (That one has an automated-manual but without dual clutches - and it even has drive-by-wire, but it's still a disaster in terms of smoothness and driveability.)

In the 1960's, power and smoothness were priorities over economy. Like it or not, that's the way it was.

Folks who weren't or aren't willing to accept the inefficiency of a traditional automatic transmission have always had the availability of a good old-fashioned row-it-yourself manual transmission ... and that's what I do.

HarveyD

Leonardo da Vinci conceptualized the CVT in 1490.

Daimler Benz built and patented a CVT in 1886

Zenith Motorcycles used CVTs in 1910

Browne used CVTs in 1922

On a comparative efficiency scale:

1. The zero shift Automated Manual Transmission (AMT) reaches 98%

2. The Manual Transmission (MT)can reach 97?, with the best drivers.

3. CVTs have reached 94% and going up with average drivers.

4. Most Automatics (AT) in use can reach 86+% with average drivers.

In principle, a 15% efficiency gain can be obtained by using AMT instead of AT. Recent CVTs are getting close to MTs and even better when average drivers are considered.

Calvin Johns

Better yet, use Toyota's HSD drive and get it all over with...

Herm

Hopefully these robotized manual transmissions will prove more reliable than the recent hydraulic AT.. lately these things have become very expensive to "repair". Perhaps they will have longer life on the dry clutches than the usual MT.

SJC

Dual clutch 6 speeds are a hot item, it they prove reliable people will be looking for them in the showroom.

HarveyD

The Toyota HDS make use of improved CVT, improved converters, e-motors etc.

CelsoS

HarveyD,

I think you're a bit confused about those transmissions. This Ford Powershift is similar to VW/VAG DSG transmissions and have nothing to do with CVT neither Toyota HSD.

BTW, Toyota HSD is NOT a CVT. It is often called a e-CVT to show people it has a function similar to a CVT while based on a completely different setup than "standard" mechanical CVTs.

From http://en.wikipedia.org/wiki/Hybrid_Synergy_Drive#Transmission:

    "This power split achieves the benefits of a continuously variable transmission (CVT), except that the torque/speed conversion uses an electric motor rather than a direct mechanical gear train connection. An HSD car cannot operate without the computer, power electronics, battery pack and motor-generators, though in principle it could operate while missing the internal combustion engine. (See: Plug-in hybrid) In practice, HSD equipped cars can be driven a mile or two without gasoline, as an emergency measure to reach a gas station.

    An HSD transaxle contains a planetary gear set that adjusts and blends the amount of torque from the engine and motor(s) as it’s needed by the front wheels. It is a sophisticated and complicated combination of gearing, electrical motor-generators and computer controlled electronic controls."

About:

    It is difficult to accept that this was not done 50 or even 60 years ago.

Previous remarks people made about the pace of embedding electronic sensors, actuators and controls are valid. Other possible enhancements like "Displacement on demand" while conceived and implemented were not a success or cost effective.

Many other potential benefits depend on perfecting electronic controls even more. Some require special sensors, some require more CPU/DSP power, some require better lab characterization an control software development.

Keep tuned to the synergy of the powerful DI ECUs with mild hybrids, start/stop, VVTL and HCCI/LTC/PPC.

HarveyD

Did anybody check what was developed in a rather short time some 50 years ago to fly people to the moon and back? The electronics and computers involved are a few orders of magnitude more complex than what is required to control the most complex mechanical power transmission and ICE.

Electronically controlled ICE and transmissions were not developed 50 years ago because the Big 3 was not interested. It was easier to use cheap AD campaigns to convince us that 2-speed AT were the best that the industry could do. What a bunch of lies that lasted 50+ years.

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