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Driver Assist Systems 101

by Ron CoganNovember 11, 2021
A growing array of sophisticated driver assist systems is offered by automakers to help make driving a safer experience. Here’s a closer look.
Driver assist system in VW I.D.4 electric car.

There was a time when sophisticated driver assist systems were the realm of luxury cars. The reason is simple, really. The cost of any new tech innovation is high, and it’s easiest to bury this cost in higher end vehicles offered at a premium price. It was thus with many innovations we now take for granted in our cars like air bags and anti-lock braking. These days, the most desired driver assist and advanced safety systems are pretty much standard fare in most new models.

We were impressed years ago when Honda launched its ‘Safety for Everyone’ program and made its latest safety innovations standard fare on all its vehicles. The auto industry as a whole has followed suit, and now even the most sophisticated systems can be found on entry-level models, increasingly as standard equipment or as available options. While drivers of premium vehicles may still be the first to experience the latest new twist operating silently behind the scenes as they drive, you can be assured the technology will filter down to all models over time.

Head up display in the Kia EV6.

Driving Safety Is Paramount

There are reasons for that because safety is always on the minds of new car buyers. The availability of systems that keep drivers and their families safe on the road, or at least as safe as possible, are highly desired. Automakers know this. Active and passive safety offer a competitive advantage in new car sales, right alongside other traditional touchstones like value, style, dependability, efficiency, and performance. If a new and highly-desired feature is introduced by one brand’s vehicles, there’s no doubt you will be seeing it offered in competitive models soon enough. There’s too much at stake for automakers not to emphasize safety, just as they emphasize electrification, efficiency, and environmental performance in their new model vehicles.

These days, technology is an active participant in our driving experience, constantly looking to warn us of unsafe conditions and offer alerts, and sometimes even initiate last-minute control to avoid an imminent collision. Their importance can’t be overstated. In the early years of driver assist systems, there were claims and assumptions regarding their promise for preventing potential collisions and saving lives. Now there is actual data to support this.

Lane mitigation systems warns of straying from your traffic lane.

Driver Assist Systems Prove Effective

Recently, GM partnered with the University of Michigan Transportation Research Institute to study the real-world effect its driver assist, active safety, and advanced headlight features were having in preventing or lessening various types of crashes. The study involved data from some 3.7 million GM vehicles across 20 models, making use of police crash report databases from 10 states. Comparisons were made involving vehicles equipped with advanced active safety features and others without this functionality.

The results showed that driver assist systems can make a dramatic difference in eliminating or mitigating crashes. Automatic emergency braking with forward collision alert was shown to reduce rear-end striking crashes by 46 percent. Lane keep assist with lane departure warning reduced lane departure crashes by 20 percent, with lane change alert and side blind zone alert bringing a reduction of 26 percent in lane change crashes.

Volvo driver assist system warns of a downed tree branch.

Even advanced lighting made a difference in driving safety. Here, high-intensity discharge headlights brought a 21 percent reduction in nighttime crashes involving pedestrians, bicyclists, or animals. In addition, advanced headlight systems that automatically turn high beams on or off in response to surrounding conditions delivered a 35 percent reduction. When combined, the two lighting systems resulted in a 49 percent crash reduction.

Advanced On-Board Electronics

Clearly, automobiles have become more complex over time. In their early years, an automobile’s electrical system was limited to fundamental functions like a starter, generator, headlights and taillights, instrumentation, and an audio system. Over the years this grew more extensive, including everything from navigation, electric-assist steering and braking, electronic transmission control, electronic ignition, anti-lock braking, an array of airbags, and advanced emissions controls.

On-board sensors identify hazards around a car.

Cameras, Radar, and Sensors

Today’s more sophisticated automobile integrates all this and more, from active safety assist systems and real-time traffic navigation to semi-autonomous driving, all enabled by on-board computers. Industry experts point out that today’s vehicles are often equipped with hundreds of controllers and sensors, and dozens of on-board computers (electronic control units, or ECUs), generating tens of gigabytes of data every hour. It’s expected that the coming generation of fully autonomous vehicles could generate upwards of 30 terabytes every day.

Supporting the electronics that process, analyze, and activate, the array of cameras, radar, and LIDAR sensors strategically and discretely positioned around a connected car ‘see’ vehicles, objects, and people ahead, around, and behind. These feed information to on-board systems that enable everything from the view seen in a back-up camera to determining the speed of a car in front of you, allowing adaptive cruise control to adjust your speed to avoid overtaking the vehicle ahead.

Panasonic driver assist system warns of a bicycle rider ahead.

These sensors are constantly evolving and improving, a necessity as we head toward fully-autonomous driving. While LIDAR continues to be a favored system by automakers, other innovations are in the works. One example is next-generation radar systems. Until now, vehicle radar has been limited to capturing just speed and direction, which is one of the reasons why vehicles use multiple sensor types for their driver assist and semi-autonomous driving features. Now, the newest long-range radar designs will determine an object’s speed, range, direction, and elevation, even at higher speeds and under challenging lighting or weather conditions.

Vehicles Have Evolved

Evolution is a hallmark of life, and it seems, of driving. Even as our cars are getting more complex in every sense as they adapt to modern life, they are also getting smarter…and safer. All that technology is delivering much more than the comfort, performance, entertainment, and driving pleasure we’ve come to expect from modern vehicles over time. We now benefit from a more confident driving experience and enhanced safety on the road as well, with technologies like those described below serving as our copilot.

Nissan ProPILOT adaptive cruise control display.

ADAPTIVE CRUISE CONTROL: As a stand-alone system or as part of semi-autonomous driving systems, ACC works like conventional cruise control with the addition of sensing technology that determines the speed and distance of the car ahead. It modifies your set cruise speed to avoid overtaking that vehicle. Many systems can bring your vehicle to a full stop if needed. Some advanced systems even reference map data to anticipate upcoming curves, roundabouts, toll booths, and more, then automatically reduce speed accordingly.

AUTOMATIC EMERGENCY BRAKING: Coupled with advance warning of unsafe closing speed or other immediate hazards, this system will automatically apply emergency braking to help avoid or mitigate a collision. Rear and pedestrian AEB is also offered as part of this system.

Blind spot detection in a Dodge Ram pickup.

Self-Driving Cars

AUTONOMOUS DRIVING: Sometimes confused with fully ‘self-driving’ capabilities not yet here or approved, to  degrees, today’s semi-autonomous systems can help keep a vehicle centered in its lane, pace a vehicle ahead at a safe distance, and often bring your vehicle to a full stop in gridlocked traffic, then resume driving when traffic in your lane is moving again. Some systems identify the pressure of hands on the steering wheel to allow continuing use of a semi-autonomous driving system, while others, like Cadillac, use a strategically-mounted camera that monitors a driver to confirm they are paying attention to the road ahead.

BLIND SPOT MONITORING: This system alerts a driver of vehicles in its blind spots to increase safety when changing lanes, passing, or being passed.

FORWARD COLLISION WARNING: Audible and visual warnings are provided to alert a driver of the potential of a forward collision. Some systems also provide brake pulsing as a further warning to gain a driver’s immediate attention.

HEAD-UP DISPLAY: A HUD projects driving information projected ahead of a driver’s view, sometimes as simple as mph but often providing info on various driver assist functions including turn-by-turn navigation.

LANE DEPARTURE WARNING: This system provides audible and visual warnings if your vehicle strays outside of its lane when a turn signal is not activated.

Night vision feature in car shows the road ahead on a dark night.

Improving Situational Awareness

LANE KEEP ASSIST: Taking over after a lane departure warning, this function provides varying degrees of steering input to help maintain lane position.

NIGHT VISION: Using infrared sensing technology, night vision displays an enhanced view of the road ahead that helps identify pedestrians, animals, or other hazards that may be beyond the view of a car’s headlights.

PARK ASSIST: This system enables a driver to select automated parallel, and sometimes perpendicular, parking functionality. It uses sensors to identify an open parking space of suitable size and the position of parked vehicles, then controls steering angle to automatically guide your vehicle into the space. Many systems require a driver to control braking, acceleration, and gear position, while others handle all functions automatically.

REAL-TIME TRAFFIC: Navigation systems that integrate real-time traffic information are valuable in saving time, fuel, and maximizing driving range with their ability to reroute around traffic jams and construction projects.

Mercedes-Benz park assist feature.

REAR BACK-UP CAMERA: Now found on a wide range of vehicles, a view to the rear is shown in a dashboard display or rear-view mirror when a driver shifts into reverse, often including grid lines depicting a driver’s angle of approach and relative distance from nearby vehicles or objects. Audible warnings are provided when objects are too close or a potential collision with an object, vehicle, or pedestrian is detected.

REAR PARK ASSIST: At low speed while in reverse, sensors detect objects and a potential collision, providing a warning brake pulse and then bringing your vehicle to a stop.

SURROUND VIEW CAMERA: This technology uses multiple cameras strategically positioned on a vehicle to provide a ‘birds’-eye’ perspective of the vehicle and its immediate surroundings.