Active wheel shutters show Ford’s aero focus for 2015 F-150

Ford's new active wheel shutters in the closed (left) and open positions on the Atlas concept pickup.

Ford’s Atlas concept pickup, unveiled Jan. 15 at the 2013 North American International Auto Show in Detroit, provides a glimpse at some key fuel-efficiency technologies engineers are readying for the 2015 F-150.

Besides the shift to high aluminum content in the front end and cab, aimed at reducing the 2015 trucks’ curb weight by up to 700 lb (317 kg) versus the current F-150, and a next-generation EcoBoost powertrain featuring auto stop-start, Ford is putting a serious focus on reducing aerodynamic drag, said Raj Nair, Group Vice President of Global Product Development.

The Atlas shows a few of the results of “our extensive aero development” on the next-generation pickup, Nair told AEI.

An unexpected feature on the Atlas is active wheel shutters. The shutters are in at-rest position behind the wheel spokes when the vehicle is stationary and at up to moderate road speeds. As vehicle velocity increases to above 60 mph (97 km/h), its wheel-speed sensors signal a dedicated battery that powers the shutters. They deploy in a fan-like pattern (think of a Chinese fan being opened), closing off the openings between the wheel spokes and thus enabling smooth airflow across the wheels.

Active grille shutters and an automatic-deploying active front air dam work in conjunction with the active wheel shutters, Nair said. The Atlas concept truck also features power running boards that tuck in close against the truck’s body at speed, also helping reduce drag.

Ford’s simulations and early testing indicate the aero package as shown on Atlas is capable of providing a fuel-efficiency gain of more than 2 mpg (0.85 km/L) at highway speeds without diminishing towing or hauling capability. Full-line automakers Ford will have to improve their light-duty trucks’ fuel economy to approximately 32 mpg to comply with the new U.S. CAFE regulations that require a 54.5-mpg fleet average by 2025.

The 2015 F-150 also is expected to feature a 10-speed planetary automatic transmission, currently under development, according to Ford and supplier engineering sources. As previously reported by AEI, Ford and General Motors are in discussions on sharing advanced transmission technology as they have done with the highly-successful six-speed transaxle program.

Other technologies revealed on Atlas that have potential for the 2015 production truck include a 360° point-of-view camera that provides the driver a “bird’s-eye” view of the vehicle; driver-controlled trailer-backup assist; dynamic trailer-hitch assist that helps line up the hitch with the trailer coupler; a dual-purpose tailgate step/cargo cradle; and LED headlamps and taillamps.

Lindsay Brooke

Schaeffler fuel-smart concept vehicle to employ several technologies developed in North America

Schaeffler's all-wheel-drive disconnect clutch will be a key technology on its upcoming demonstration vehicle.

In the coming weeks, technical specialists will equip a MY2013 Ford Escape with several fuel-smart innovations from Schaeffler, including its thermal-management module, AWD disconnect clutch, permanently engaged starter/generator, and latching valve. The latter three technologies were conceived and developed in North America.

“We think we’re under $40 per percent of fuel-economy improvement,” Jeff Hemphill, Vice President and Chief Technical Officer for Schaeffler Group North America, said in an interview with SAE International Magazines at NAIAS.

The thermal-management module to be fitted on the vehicle demonstrator (called Efficient Future Mobility North America) will be similar to the Schaeffler unit used by Audi in some production vehicles.

“But this version won’t have quite as much functionality,” Hemphill said about the module that allows the optimum engine temperature to be reached in the shortest time possible and allows temperature balance to be precisely controlled.

Integration of a thermal-management module can provide a 1% reduction in fuel consumption for city and highway driving.

Schaeffler’s AWD disconnect clutch, which decouples the unused drive axle from the drivetrain depending on the driving situation, can generate fuel savings of up to 2% in city driving and up to 6% in highway driving. The permanently engaged starter/generator with a wrap-spring one-way clutch can provide up to 6% fuel savings in city traffic.

The AWD disconnect clutch, the permanently engaged starter/generator, and the latching valve are all second-generation, under-development technologies. “These technologies could start production development later this year [and] enter production in the 2017 model year based on their maturity,” said Hemphill.

Schaeffler’s SUV demonstrator is expected to be ready for ride-and-drive evaluations in the summer of 2013.

According to Hemphill, the initial demonstration vehicle with its conventional powertrain and fuel-smart Schaeffler technologies is designed to meet CAFE standards for 2020. The company's follow-up demonstrator vehicle will add hybrid systems, with the goal of fulfilling CAFE requirements for 2025.

Kami Buchholz

Electronics diverge in engineering Ford's hybrid C-Max and plug-in Energy

Large cell compartment for plug-in holds electronic modules, which are (1) battery temperature sensor; (2) junction box; (3) battery energy controller; (4) DC-DC converter controller; (5) secondary on-board diagnostic module.

Turning a hybrid electric vehicle (HEV) into a plug-in hybrid (PHEV) is more than adding cells to a battery pack, reflashing the controller, and installing a charger. The 2013 Ford C-Max and C-Max Energi are examples of what it takes to develop conventional hybrid and plug-in versions of the same vehicle—that is, many specific parts, software, and validation.

Both cars have lithium-ion (nickel-manganese-cobalt oxide) cells, which are chemically very similar. But those in the plug-in C-Max Energi, which has a 21-mi (34-km) EV range, have thicker electrodes and store more energy.

Why wouldn’t the C-Max conventional HEV have the same electrode thickness? Because thinner electrodes have less impedance, so the cells (of which there also are fewer) can deliver electric power faster. HEV batteries are a power source for acceleration assist, only minimal EV operation.

Designing for dual function

PHEV batteries, however, primarily are an energy source and, for EV operation, must be able to discharge deeply and take repeated recharge cycles over many years. But once EV energy is depleted, plug-in cells also must function in HEV mode. So electrodes’ design and other aspects of energy cells are a balancing act.

The prototype Prius PHEV evaluated the idea of a pair of cell packs: one type, larger for plug-in EV operation, the other (smaller) engineered for hybrid mode when the larger one's capacity was depleted. But the production model has one pack doing double-duty and controller software to optimize each function. That's the approach all other makes including Energi also have taken.

The “full” or conventional HEV version of the C-Max has 76 of the power cells wired in series, rated at 1.4 kWh. The plug-in Energi has 84 of the energy type in series, rated at 7.6 kWh. The plug-in uses 6.5 kWh for EV range and allows a residual of 1.1 kWh for HEV operation.

The physical size of the Energi PHEV pack, of course, is much greater. The HEV cells are each 120 x 85 x 13 mm (4.72 x 3.35 x 0.51 in); the Energi's are 148 x 91 x 26 mm (5.83 x 3.58 x 1.02 in). And the Energi pack has higher peak voltage (361 vs. 327, during regenerative braking). There's comparable HEV capacity for such operations as idle stop/restart, Ford engineers said.

Battery temperature controls

Battery temperatures are important factors for PHEV range, cell life, and performance. According to Gilbert Portalatin, Ford's Chief Program Engineer, Electrified Powertrain Programs and Integration, tests are run at extremes of -35ºC (-30ºF) and 82ºC (180ºF).

EVs such as Ford's Focus and the Chevrolet Spark variants, and even the plug-in Chevy Volt (all with much higher-capacity battery packs), have an active electric-pump-driven heating and cooling system using liquid coolant and siamesed in a heat exchanger with the vehicle HVAC. The object is to keep pack temperatures within 0-30°C (32-88°F), a protective range for fast recharging systems.

C-Max and Energi employ only fan-driven air-heating/cooling systems, relying on a sensor to monitor battery compartment temperatures. The Energi employs control strategies to direct cell temperatures to within 0-45ºC/32-113ºF for maximum EV driving range.

If the battery pack temperature is lower, the Energi will operate in EV at reduced power until the cells warm up during normal cycling of electricity between generator and battery pack, from drive operation and regeneration. There also may be heat provided by airflow through ductwork from the cabin if the climate control is in the heating mode.

There certainly will be heated air blown into the battery compartment from the cabin if the Energi's engine is started.  This occurs when the defroster is turned on or if the weather is extremely cold (the 2013 Chevy Volt also may employ a similar engine-start algorithm for battery pack heating in extreme cold).

For hot weather, the C-Max fan draws in what will be cooled cabin air provided by the vehicle A/C. During Energi-recharging, the fan draws in outside air, which even in hot weather is likely to be cooler than the cabin of a parked car in a hot soak. The Energi also will have a preconditioning mode using A/C for cabin cooling during plug-in, enabled through the Sync or MyFord Touch modules.

Ford has seen no durability problem with its battery pack from hot soak itself, Portalatin told AEI. So long as the vehicle is parked, peak temperatures in the battery compartment don’t affect battery capacity or longevity. Once the Energi is in use and the A/C is turned on (which can be assumed in very hot weather), pack temperatures quickly lower to an acceptable level.

This approach contrasts with the pre-2010 Ford Escape HEV, which used nickel-metal hydride batteries susceptible to deterioration if operating temperatures exceeded 140ºF (60ºC). It employed a second, rear HVAC system with an evaporator and a refrigerant flow control circuit that would chill the fan-driven airflow to the battery pack.

Innovative algorithm

In addition, C-Max Energi has algorithms that can adjust the EV range for the driver’s chosen route or operating choices, one of which is particularly innovative.

It can recognize a familiar route that is very close to the maximum EV range of the vehicle and do “smart discharge.” Using GPS from Sync to determine location along the known route, the system controls power output to extend range without changing the maximum percentage of discharge. This may make it possible for the car to reach its destination without gasoline engine operation. Other algorithms, similar to those in competitive PHEVs, permit the driver to choose when to use plug-in power, including reserving it, such as for lower-speed urban operation.

Ford limits the Energi to a 3.3 kW charge rate with a Level 2 (208-240-volt) system, which is part of the thermal balance with the protection from air cooling. The small battery pack takes just 2.5 hours for full recharge. By comparison, the Focus EV, with its active liquid cooling, accepts a Level 2 charge at a 6.6 kW rate.

Motor electronics for all full and plug-in hybrids rely on liquid cooling, typically with a dedicated electric-pump circuit, under the hood.

Paul Weissler

The Ducati Dry Clutch and Its Distinctive Rattle

Just as you can tell when a Harley is somewhere in the vicinity by the distinctive rumble of its V-Twin, so can you tell when a Ducati has just pulled up next to you.Although many might think that the rattling sound coming from a Ducati is a sign that the bike is in dire need of a tune-up, the bike is in fact perfectly fine. What you are hearing is the signature sound of the Ducati dry clutch, which is music to the ears of many a Ducati enthusiast.

Dry vs. Wet Clutch

It may seem obvious to many of our readers, but let us remind you of the difference between wet and dry clutches. The wet clutch, which you’ll find on just about every bike, is bathed in oil and completely sealed off. Dry clutches, on the other hand, are totally free of oil and do not need to be sealed. Many dry clutches are exposed so that the spinning clutch plates are visible to any passerby.

Pros and Cons of a Dry Clutch

Since Ducati employs the dry clutch on most of their bikes, we’ll take a quick look at the pros and cons of such a set up.

Pros:

1. Easy access for repairs. There is no need to drain the oil before removing the clutch cover if you need to service your clutch. This is especially important in racing where clutches are regularly burned out and need to be replaced immediately.
2. The dry clutch does not share oil with the rest of the engine and thus any debris from disintegrating clutch plates will not harm engine internals.
3. Submerging a clutch in oil creates drag which will diminish the engine’s horsepower; it might not reduce the horsepower by much, but every little bit counts on the track.
4. Heat generated by the clutch plates does not heat up the engine’s oil, which is especially important for bikes in which oil is used in the cooling system.

Cons:

1. Much louder, but this is a matter of preference.
2. With an exposed dry clutch, the springs will eventually rust. This can be prevented by installing stainless steel springs.

Why Does Ducati Use Dry Clutches on Most of its Bikes?

As you’ve probably gathered from the above list, dry clutches are most useful on race machines. For that reason, many will argue that Ducati’s use of a dry clutch on street bikes is only for marketing purposes.
In the past, Ducati has claimed that they build all their bikes to racing specs and that means using a dry clutch. However, in recent years, Ducati has produced bikes whose specifications are more in line with the target audience.
Today, bikes such as the Ducati 848 and Monster 1100 Evo are equipped with a wet clutch for easier use.

Why The Ducati Dry Clutch Sounds Like Rocks in a Bucket

If you’re still wondering what exactly it is that makes the Ducati dry clutch sound like someone put marbles in it, here’s your answer. The sound you’re hearing is the clutch plates bouncing off of one another when the clutch is disengaged.You’ll hear this sound when a Ducati rolls up next to you at a stop sign and the rider has pulled in the clutch lever, freeing up the plates to knock into each other.
Without any oil surrounding the clutch pack to lubricate the plates, you get that distinctive sound of rocks in a bucket.
So next time someone pulls up next to you on a Ducati, you’ll know better than to yell to them that they should get their valves adjusted.