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NOTE: This article was written in 1997 and is obviously out-of-date, but is it still interesting to read from a historical perspective...
One thing you can count on to remain the same is change. Automotive technology continues to evolve at an ever quickening pace, and the changes that are coming will continue to challenge those who have to fix tomorrow's cars (and trucks). To get an idea of where we are going, we need to consider where we have been and where we are at today.
In the past 20 years, the changes that have taken place are nothing short of remarkable. Twenty years ago front-wheel drive was a European novelty. Who would have thought that in a few short years, it would revolutionize the entire automotive industry and completely revamp passenger car design forever? The same with aero styling, plastic composite bumpers, soft facias and fenders, and many of the other features that have since become an integral part of today's vehicles.
Front-wheel drive is now firmly entrenched, so there is little doubt that tomorrow's cars will likely continue the tradition of front-wheel drive because of its packaging advantages. Trucks will stick with rear-wheel drive because that arrangement works best for larger, heavier vehicles. Four-wheel drive will continue to be offered on a limited basis for vehicle applications that need the extra traction, but will work even better than most of today's systems thanks to the added traction assist provided by state-of-the-art ABS/traction control systems.
The introduction of the minivan back in 1984 by Chrysler created a whole new vehicle niche that continues to this day and will likely remain for the foreseeable future. The same with Sport Utility Vehicles (SUVs) that are currently all the rage. Tomorrow's car may just as well be a truck.
As the Baby Boomer generation ages, though, there may be a move away from family oriented vehicles such as mini-vans and large four-door SUVs back towards luxury cars or some type of smaller truck/SUV platform. Many people like the size and utility of trucks, especially now that many trucks are engineered to ride and drive like cars. So look for more car-like trucks or truck-like cars in the future.
Twenty years ago, antilock brakes were virtually unheard of and would not be introduced to the U.S. market until 1985 when the first Audis, BMWs and Mercedes with Bosch ABS were imported into this country. In 1971, Chrysler offered a mechanical anti-skid system as an option on the Imperial. But it wasn't until 1986 that Ford and GM offered state-of-the-art electronic ABS systems on the Lincoln Mark VII and Continental., and the Chevrolet Corvette. In the 1990s, ABS because available on almost all passenger cars and virtually all pickup trucks, sport utility vehicles, vans and minivans as either standard equipment or an option. However, ABS was not required by law until 2013.
ABS systems have become more complex and compact at the same time. Over the years, ABS has evolved from a simple antiskid brake control system into a comprehensive traction control system that prevents the wheels from losing their grip during all modes of driving. The current trend in ABS is to expand its role even more to include all-round stability control and steering assist.
In 1997, Cadillac introduced a new "Integrated Chassis Control System" (ICCS) on the Seville, Eldorado and DeVille that automatically applies either front brake to counter understeer or oversteer when cornering. The technology is similar to a system developed by Bosch that appeared a year earlier BMWs, and an even more sophisticated system which is offered on "S" class Mercedes sedans and E420 models. Called "Electronic Stability Program" (ESP), the Bosch system on the Mercedes applications can brake any of the vehicle's four wheels to correct steering maneuvers for enhanced handing and stability.
This new technology is worth looking at for a moment because it is a preview of what is coming on more and more vehicles in the years ahead. On the Cadillac application, steering inputs are monitored by a column-mounted digital steering angle sensor. Under the parcel shelf is a yaw sensor that uses a pair of tiny ceramic tuning forks to sense the turning motions of the vehicle. A third sensor measures lateral acceleration and helps the ICCS system keep tabs on acceleration, deceleration and overall traction.
If the vehicle begins to understeer or oversteer while cornering, the system detects the discrepancy between the actual and desired yaw (turning) rate, and automatically applies individual front braking to slow the car and help steer it back on course.
When a vehicle understeers, it does not respond quickly enough to the driver's steering inputs and plows to the outside when rounding a curve at high speed or when making a sudden lane change or similar steering maneuver. The Cadillac ICCS system corrects understeer by braking the inside front wheel. The braking force pulls the car back on course and neutralizes understeer much like dragging a paddle on one side of a canoe turns the canoe toward that side.
With oversteer, the back end of the car drifts to the outside and wants to swing around. Unless control is regained, this can lead to a sudden spin out. The ICCS system handles oversteer by gently braking the outside front wheel. The braking force slows the vehicle and nudges the tail back into line.
Cadillac says the ICCS system is like having an expert copilot take control and provide assistance when the driver needs it most. It is full time and fully automatic, and makes a considerable difference in the way these cars handle curves and sudden steering maneuvers.
What is next? How about a brake system that "anticipates" a panic stop and applies the brakes faster than the driver normally would? Such a system will be offered on certain 1998 Mercedes models. The system monitors the driver's normal braking habits so it learns to recognize a panic stop. This allows the system to immediately apply full braking to shorten the stopping distance of the vehicle.
A little further down the road are collision avoidance systems that use infrared or radar sensors to detect objects in the road ahead. Such systems will supposedly automatically brake or steer to avoid a collision. The first application of this new technology will actually be adaptive cruise control systems that do not just maintain a constant speed but automatically adjust speed to maintain a safe following distance behind the vehicle ahead.
Another change that may be coming with respect to brakes are fully-electronic brake-by-wire systems that have no hydraulics at all! Continental Teves has developed an electronic brake caliper that uses a small electric motor to apply the brake pads rather than a hydraulic piston. The advantage with this technology is that it could eliminate a lot of expensive plumbing while simplifying ABS braking/traction control and stability control by allowing the brakes to be controlled directly rather than relying on pumps, solenoids and hydraulic valves.
Twenty years, air bags were considered a flop. General Motors offered air bags as an extra cost option on selected models from 1974 to 1976, but dismal sales (only about 10,000) and a lack of public acceptance led GM to conclude that nobody wanted air bags. Who would have thought that 10 years later air bags would be one of the hottest and most-sought after safety features?
As air bag technology continues to evolve, so do new applications for inflatable restraints. First it was driver air bags, then passenger air bags, now side air bags. The latest addition is a new "Head Protection System" that pops out of the A-pillar and roof in a side impact to protect the head and neck. The first such system will be offered in 1998 by BWM as standard equipment on 7-Series models and certain 740i models.
BMW calls their device an "Inflatable Tubular Structure" (ITS) rather than an air bag because it remains inflated after an accident. BMW says this helps protect the occupants from subsequent collisions following the initial impact, and prevents them from being ejected out the side windows. The ITS is concealed above the front doors and within the A-pillar and roof upholstery. The tube is about five feet long and measures about 1-1/2 inches in diameter when uninflated. Upon side impact, a sensor triggers the ITS inflator which is located behind the front kick panel (one on each side). The tube on the side of the impact inflates and bursts out of its hiding place to form a protective barrier that stretches from the lower front corner of the side window to near the top of the B-pillar.
Another development in the ongoing evolution of air bag technology are "Next Generation" bags that start appearing in certain 1998 models. These air bags deploy with reduced force to lessen the risk of injury in low speed crashes. Who would have thought that a device designed to save lives would be responsible for the deaths of nearly 40 children and over 20 adults (mostly small women)? After much hand-wringing, finger-pointing and debate, the National Highway Traffic Safety Administration (NHTSA) revised its test procedures and requirements to allow the kinder, gentler air bags. The new air bags are designed to deploy with 20 to 35% less force than current bags, which should provide adequate protection for belted occupants while reducing the risk of injury to unbelted occupants (especially small children and adults) in low speed accidents.
Coming soon is a whole new generation of "smart" or adaptive air bags that modify their deployment force to match different vehicle speeds and whether or not a person is wearing a seat belt.
The big question regarding the future of air bags is who is going to pay for their replacement following a deployment in an accident? With more and more bags being added every year in every conceivable nook and cranny, the cost to replace multiple bags following an accident can be considerable and may even exceed the valve of some older vehicles. Some insurance companies already balk at paying for expensive air bags, and many motorists are not willing to fork over hundred of dollars out of their own pockets to pay for replacement air bag modules.
As the use of electronics in today's vehicles becomes more and more pervasive, so to does the complexity of repairing collision damaged vehicles. Electronic suspensions initially appeared to be the wave of the future. But their high cost failed to justify the marginal improvement in ride quality and handling for most applications. Consequently, some of the more exotic electronic suspensions have been dropped in favor of conventional struts and springs.
Electronic suspensions will continue to have a niche in luxury sedans and similar applications, but their use will remain limited. The newest technology that has yet to find its way onto a production application are electronic shocks and struts that contain a special magnetic fluid that thickens and changes viscosity when an electric current is applied to it. This type of damper could provide infinitely variable shock rates that react to changing road conditions almost instantly without the use of expensive solenoids or stepper motors.
Twenty years ago, rack & pinion steering was making inroads in small car applications, but had yet to achieve the mainstream status it enjoys today. Many current rack & pinion steering systems have variable assist that change the amount of power assist based on vehicle speed and driver input. The next generation systems will likely be electric steering systems rather than hydraulic to reduce the bulk and complexity of today's power steering gears. Such systems have already been developed and are in limited use on a few exotic car applications (such as the Acura NSX). Electrically-powered steering racks are said to be 85% more energy efficient than a conventional hydraulic system, and can be programmed to provide proportional assist and dampening. Electronic steering may also eliminate the need for a conventional steering wheel.
Eventually, we will have cars that steer and drive themselves, but do not count on snoozing behind the wheel for at least another 20 years. This technology must be proven absolutely fail-safe before it can come into general use. Limited use for certain applications like public buses, however, may be just around the corner because systems are now available that can pilot a vehicle along a prescribed route that has a wire buried in the road.
When emission controls were introduced back in the early 1970s, nobody foresaw the evolution of today's complex computerized engine control systems. But since 1981 (1980 for California vehicles) computerized engine controls have been a fact of life.
The systems continue to grow in capability and complexity. Carburetors have been obsolete for over a decade now, replaced by multiport fuel injection systems. The latest trend here may be the growing use of "direct injection" where the fuel is injected under high pressure directly into the combustion chamber rather than the intake port. Benefits are lower emissions, up to 10% more torque and 35 to 40% better fuel mileage. Mitsubishi now has such an engine in production.
As for computerized engine controls, the earliest systems were only concerned with regulating the fuel mixture, ignition timing and a handful of other relatively simple tasks. The control modules were rather simple 8-bit microprocessors with limited diagnostic ability. Today, 32-bit microprocessors with as much computing power as a home personal computer are found on many vehicles, and the current onboard diagnostic II (OBD II) systems provide extensive diagnostics including the ability to detect ignition misfires, evaporate emissions from the fuel tank and the operating efficiency of the catalytic converter.
On the plus side, OBD II has brought some much needed commonality to repairing computerized engine controls thanks to a standard diagnostic connector and standardized diagnostic trouble codes (DTC). But on the downside, diagnosing these systems has become even more complex and requires even a higher level of skill than before. It also requires a whole new generation of OBD-II compliant scan tools (which will have to be updated yearly).
Electronics have also changed today's powertrains. Most of the automatic transmissions and transaxles are now computer-controlled, which blurs the distinction between engine driveability problems and those caused by a malfunctioning transmission. There is also more communication and interaction between the ABS/traction control system and Powertrain Control Module (PCM), which further complicates the matter of solving the cause of a Check Engine or Malfunction Indicator Lamp being on. The only prediction we can make here is that the underlying technology will continue get more complicated but hopefully the diagnostics will get easier.
Fly-by-wire throttle controls are another change that is coming, which means the days of the mechanical throttle linkage are numbered. Again, the Europeans are the first to apply this new technology. By connecting the gas pedal to a rheostat or position sensor, engine speed can be "optimized" electronically for improved fuel economy, emissions and performance.
First is was simple things like cassette players, then CD players, then MP3 players. Then came the cellular phone revolution, which has gone from installed cell phone to portable phones. Then came the first electronic navigation systems which used satellite reference signals to determine the vehicle's position on an electronic map. This technology may soon become part of a "smart" highway system that combines satellite tracking with traffic routing instructions to help relieve urban congestion (good luck!).
One of the most practical applications of navigational technology, cell phones and two-way communications, however, is the Cadillac OnStar system that provides immediate roadside assistance in the event of an accident. If a crash causes the air bags to deploy, a distress call is immediately sent out that summons help. It is a really slick system that is bound to grow in popularity. Look for this type of system on more and more applications in the years ahead.
Another change that may take place in onboard electronics is greater use of multiplexing. This is the sharing of a common wire or circuit by multiple devices to reduce the complexity and bulk of the wiring system. Multiplexing has been used on some luxury cars, but its high cost has limited its general use across the board. This may change as costs come down. Further out is the possibility that copper wires may be replaced altogether. Engineers are working on a new generation of "opti-electronics" that uses pulses of light traveling through fiberoptic cables to transmit data rather than electrons in a wire.
Lighting may also take the same approach. Instead of having numerous individual lamps for all of the lights, the lighting system may have one or two common light sources that distribute light via fiberoptic cables. The use of High Intensity Discharge (HID) lighting (similar to fluorescent lighting) may also grow because of its superior output.
Also, look for more new cars with daytime running lamps. Like the center high mounted stop lamps that were introduced a number of years ago, daytime running lamps improve visibility to other motorists and help reduce accidents.
One component that must often be replaced when a vehicle is involved in a frontal collision is the refrigerant in the vehicle's air conditioning system. If the evaporator in front of the radiator is damaged, the refrigerant leaks out requiring not only the evaporator to be replaced but the refrigerant also.
Until the ozone issue came up, every vehicle contained the same type of refrigerant" R12. But with the phase-out of R12, a number of alternative refrigerants have appeared for converting older vehicles with R12 systems. All 1995 and newer vehicles have the new ozone-safe R134a refrigerant, which can be used in many of the older systems once a few modifications have been made. The problem, though, is figuring out what type of refrigerant was in a vehicle prior to the accident, and what type of refrigerant to put in it when repairs are made.
The current recommendation by the vehicle manufacturers is to replace same with same as long as R12 is still available. But the soaring price of R12 is making it a very expensive commodity these days, costing upwards of $20 a pound. So it may be less expensive to convert a damaged R12 system over to R134a or some other refrigerant when repairs are made.
For now, any shop that does A/C repairs should have some type of refrigerant identifier equipment to prevent cross-contamination of refrigerants. Proper recover and recycling procedures must also be followed to comply with the law and to prevent cross-contamination of recycled refrigerant. It will be many years before this problem goes away. We do not expect any new refrigerants to be introduced (in addition to the half dozen or so alternatives that are currently on the EPA "accepted" list), but we do foresee some changes in the packaging of the A/C system itself.
One of the reasons why A/C systems leak refrigerant is because they have a lot of flexible hoses and couplings. If automotive A/C systems were modular in design like those inside a refrigerator, refrigerant leakage would be a thing of the past. So look for modular A/C systems driven by an electric motor to appear sometime soon.
Some technologies seem like a sure-bet but fail to pan out for various reasons. Among the losers:
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