Brake Assist in Cars: What Is It & How Does It Work
What is Brake Assist?
Brake assist is a safety system in cars that provides additional brake force in emergency situations where the driver does not brake hard enough. According to https://caradas.com/understanding-adas-brake-assist/, brake assist detects when a driver slams on the brakes in an emergency situation, but does not apply enough brake pressure for maximum stopping power. In this scenario, brake assist automatically increases the brake pressure to provide full braking capacity.
The main purpose of brake assist is to reduce the braking distance needed to bring the vehicle to a stop in an emergency. By providing maximum brake force, brake assist aims to compensate for situations where a driver may not brake hard enough due to being startled or overwhelmed by the emergency. This can help avoid collisions or minimize impact speed in crash situations.
At a high level, brake assist works by monitoring how fast and how hard the brake pedal is pressed. When sensors detect emergency braking, but not maximum pressure, brake assist kicks in to apply full braking force. This activates the anti-lock braking system to stop the wheels from locking up and help maintain control of the vehicle.
How Brake Assist Works
Brake assist works by using sensors to detect when the driver slams on the brakes in an emergency situation. When rapid or hard braking is detected, the brake assist system applies additional force to the brakes, beyond what the driver is applying through the pedal.
This helps the driver stop faster and shorten the braking distance in an emergency situation. The additional brake force provided by brake assist can reduce stopping distances by 5-10%.
According to How Stuff Works https://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/brake-assist.htm, the brake assist system uses a hydraulic pump and valves to increase the brake fluid pressure when emergency braking is detected.
Overall, brake assist senses hard braking and helps apply maximum braking force, assisting the driver in stopping as quickly as possible in an emergency situation.
Benefits of Brake Assist
Brake assist offers several key benefits for drivers:
First, brake assist can dramatically improve stopping distance in emergency situations. By detecting panic braking, the system activates the maximum braking pressure to bring the vehicle to a halt as quickly as possible. This shortened stopping distance gives the driver more time to react and can be the difference between a near-miss and an accident.
Second, by improving emergency braking, brake assist helps prevent accidents. Studies have shown vehicles equipped with brake assist are involved in fewer collisions. The safety benefits are clear – fewer accidents mean fewer injuries.
Finally, brake assist provides peace of mind for drivers. Knowing the vehicle can deliver full braking force in an emergency gives confidence behind the wheel. Drivers can react naturally in a panic situation, without worrying about whether they are braking hard enough. This reassurance is invaluable, especially for less experienced drivers.
In summary, quicker stopping, increased accident avoidance, and driver reassurance are the main benefits offered by brake assist technology.https://www.hondainfocenter.com/Shared-Technologies/Safety/Brake-Assist-All/
Types of Brake Assist Systems
There are two main types of brake assist systems:
Basic Brake Assist
Basic brake assist, also known as mechanical brake assist, uses a mechanical vacuum pump and booster to increase braking pressure when the system detects an emergency braking situation[1]. This is one of the earliest forms of brake assist and is found in older vehicles. Basic brake assist provides limited assistance and doesn’t adapt to different braking conditions.
Advanced Brake Assist
Newer vehicles are equipped with advanced, electronically-controlled brake assist systems. These use sensors and computer control to modulate braking pressure and provide more intelligent assistance in emergency situations[2]. Advanced systems like Mercedes-Benz’s Adaptive Brake Assist can detect emergency braking based on how quickly the driver steps on the brake pedal. Advanced systems provide more tailored braking assistance than basic brake assist.
There are differences between manufacturer systems as well. For example, some vehicles like certain Lexus models have a Brake Assist System that only activates if the anti-lock brake sensors detect wheel slip during hard braking[1]. Other systems activate whenever the brake pedal is depressed rapidly.
[1] https://en.wikipedia.org/wiki/Emergency_brake_assist
[2] https://caradas.com/understanding-adas-brake-assist/
When Does Brake Assist Activate?
Brake assist systems are designed to detect emergency braking situations and provide additional brake pressure when needed. The main thresholds that trigger brake assist activation are pedal pressure and vehicle speed:
Most brake assist systems activate when the brake pedal is pressed quickly and with significant force, indicating an emergency stop. There is typically a threshold of pedal pressure that must be exceeded. For example, Mercedes-Benz brake assist activates when pedal force exceeds a certain rate of pressure increase.
Vehicle speed also factors in. Brake assist will only activate above a minimum speed, usually around 4 mph. This prevents false activations when braking from very low speeds. Faster speeds generally require less pedal force to trigger brake assist.
Different manufacturer systems have varying sensitivities. Mercedes-Benz brake assist tends to activate with lighter pedal pressure compared to other brands. Luxury brands also activate at lower speeds than mass market vehicles.
Limitations of Brake Assist
While brake assist can provide valuable emergency braking assistance, it’s important to understand the system’s limitations:
Brake assist only aids in emergency braking situations where the driver steps forcefully on the brake pedal. It does not automatically apply the brakes or override driver inputs in normal driving conditions (https://www.jdpower.com/cars/shopping-guides/what-is-mercedes-benz-brake-assist).
Physics still apply – brake assist cannot stop a vehicle instantaneously or override physics. Factors like vehicle speed, road conditions, visibility, and tire tread will impact stopping distance even with brake assist (https://caradas.com/understanding-adas-brake-assist/).
The system relies on proper maintenance and operation of the vehicle’s braking system components. Issues with brake pads, rotors, hydraulic fluids or the ABS module can impair brake assist functionality.
While a valuable safety feature, drivers should understand brake assist is not a substitute for attentive driving. It is designed to supplement, not replace, an alert driver’s braking abilities in an emergency situation.
Brake Assist vs Anti-Lock Brakes
Brake assist and anti-lock brakes are two important braking assistance systems in cars that work together to improve braking performance. There are some key differences between the systems:
Brake assist detects emergency braking situations and applies full braking force even if the driver does not press the brake pedal firmly enough. Anti-lock brakes prevent the wheels from locking up during hard braking so the driver can still steer the vehicle. Brake assist is triggered in panic situations while ABS activates whenever the wheels are close to locking.
Brake assist provides maximum braking power in emergencies, while ABS allows steering control to be maintained. Brake assist can increase braking force up to the point of locking the wheels, then ABS takes over to release brake pressure and prevent lockup. These systems work together to stop the vehicle as quickly as possible while maintaining steering.
In summary, brake assist optimizes braking power and force in emergency situations based on how quickly the brake pedal is pressed. Anti-lock brakes allow the wheels to keep turning so the vehicle remains steerable during heavy braking (Source: https://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/brake-assist.htm). Brake assist and ABS complement each other to maximize braking performance and control.
History of Brake Assist
The first brake assist systems were introduced in the 1990s by Mercedes-Benz and BMW. Mercedes-Benz unveiled its Brake Assist System (BAS) in 1996 on the S-Class and SL-Class models. It used sensors to detect emergency braking and automatically increase braking pressure to reduce stopping distance. BMW followed with a similar system called Dynamic Brake Control in 1997.
In 2001, Toyota introduced a more advanced Electronic Brake-force Distribution (EBD) system, which could vary the braking force on each wheel based on conditions. This helped prevent wheel lock-ups and maintain stability. Honda also unveiled a Collision Mitigation Brake System in 2001, which could detect impending collisions and prepare the brakes.
By the mid-2000s, brake assist technology had evolved to use radar, cameras, and other sensors. Mercedes added its Pre-Safe Brake system in 2006, capable of detecting imminent rear-end collisions and autonomously braking. Volvo also introduced Collision Warning with Full Auto Brake in 2006, which used radar to identify potential front collisions.
Today, most modern cars come equipped with advanced emergency brake assist systems that can detect a wide range of potential accident scenarios and autonomously apply brakes much faster than a human driver could respond.
Sources:
[1] https://en.wikipedia.org/wiki/Emergency_brake_assist
[2] https://www.abebrakes.com/en/information-en/the-history-of-braking-systems/
Future Brake Assist Innovations
Brake assist technology continues to advance and improve through ongoing research and development. Some key areas of innovation for the future include:
Integrating brake assist with other driver assist technologies: Brake assist can be combined with features like adaptive cruise control, automatic emergency braking, and lane keeping assist. By linking brake assist to these other systems, braking response times can be even faster in critical situations. For example, if a car’s forward radar detects slowed traffic ahead, brake assist can prepare to activate the moment the driver hits the brake pedal.
Improving response times: Brake manufacturers are constantly testing new hardware and software designs to achieve faster brake assist system activation and braking. For instance, Continental is developing a MK C1 brake system that can initiate full emergency braking in just 150 milliseconds after detecting a hazard [1]. Faster response times will enable more collisions to be avoided through brake assist.
New braking technologies like brake-by-wire are also poised to reduce response times by removing bulky and slow hydraulic components from the braking process [2]. These next-generation braking systems will allow brake assist to activate the moment pressure is applied to the brake pedal.
Key Takeaways
Brake assist is an important safety system in vehicles that detects emergency braking situations and applies maximum braking power to help drivers stop quickly. Key points about brake assist include:
– Brake assist detects when drivers suddenly brake hard, indicating an emergency situation where maximum stopping power is needed.
– The system applies full brake pressure, even if the driver doesn’t press the pedal hard enough in a panic.
– This can help shorten stopping distances by around 25%, improving safety.
– While anti-lock brakes prevent wheels from locking, brake assist also maximizes braking in emergencies.
– Brake assist works in concert with components like electronic stability control.
– The technology first appeared in the late 1990s and is now standard in most vehicles today.
– Ongoing innovation aims to make brake assist systems even faster and more effective.
Having brake assist can greatly benefit driver safety in emergency situations. Drivers should still focus on attentive driving and safe following distances. But brake assist provides an extra measure of protection and reaction time.