How Traction Control works?

The orange triangle with arrow warning light is ASC (Automatic Stability Control), BMW's speak for traction control

New cars are complicated huh? Browse carefully the sales brochure and you will inevitably stumble upon a list of fancy sounding safety features that will make your eyes glaze. For the purpose of this post, one of those fancy sounding feature include Traction Control. So what is it then and how does Traction Control works?

So what on earth is Traction Control??

   

  Source: Wikipedia

Imagine it's a rainy day. You're about to take off from standstill and simply plant the gas pedal to the floor. The next thing you knew, your car is barely making forward progress and fishtail as your driven wheels spin up like crazy. This is where Traction Control comes in.

In the same scenario with Traction Control, the system detects you're giving too much gas and the driven wheels, since it's sitting in a deep puddle of water, have zero grip to safely accelerate the car without risking lost of control and potentially causing accident. 

The computer that governs the Traction Control system will either apply the brakes on the slipping wheels or briefly retard the engine to reduce the power going to the driven wheels, hence slowing it down until the wheels restore grip.

In essence, Traction Control works sort of like Anti-lock Braking System (ABS) in reverse. Where the latter works when you're stopping the car, the former works when you're accelerating. Unlike ABS which works on all 4 corners, Traction Control only works on the driven wheels; front wheels on Front Wheel Drive, rear wheels on Rear Wheel Drive and all 4 wheels on All Wheel Drive.

How does Traction Control works?

In vast majority of modern vehicles, Traction Control works in tandem with ABS in that it shares the same ABS wheel speed sensors and hydraulic modulator that pumps the brakes. The sensor monitors for differences in wheel speed of the powered wheels and communicate the information to the system's control unit. 

If large speed differential is detected between the driven wheels, the control unit recognises onset of wheelspin and employ the brake on the problematic wheel, pumping the brake pressure ABS style to bring the wheel back to normal speed.

Other than applying the brake, the control unit can also momentarily cut engine power. The interruption in power delivery slows down the driven wheel until normal rotational speed is established.

My E46 320i employs similar concept, in that the Traction Control (known as Automatic Stability Control or ASC by BMW) is integrated with the ABS unit. If there's a malfunction, both the ABS and Traction Control warning light will light up. 

When is it effective?

Traction Control works wonder when driving over low grip surface which includes but not limited to rain-soaked asphalt, gravel, grass, mud and snow.

I can vouch from my personal experience with my E46. When I get too punchy with the gas on gravel, grass, road humps and flooded road, the Traction Control light flash away like a parent scolding their kids for misbehaving.

The feature is effective during hard acceleration from standstill or low speed crawl as at this point of time your transmission is technically locked in lower gear. Lower gear = more power going to the wheels. At higher speed, wheelspin is less likely to happen as you'll be driving in higher gear, but still a possibility if grip level is abnormally low or you just drop Bugatti's engine in your mom's Camry. 

However, Traction Control can be a double edge sword. Imagine if your car is stuck in deep snow. In this situation, Traction Control can cut precious power that can be the difference between getting unstuck or remain rooted in the snow. It's therefore recommended that you briefly turn off the system to help you rock your car out of snow and reactivate the system after you're safely unstuck.

Safety Demonstration - ESC, AEB, Blind Spot Monitoring and tyre safety

Driving safety is definitely of paramount concern to every individuals. With road accident on the rise, Global NCAP (New Car Assessment Programme) see it fit to organise the Stop the Crash event in an effort to raise awareness on the importance of safety behind the wheel. 

Just recently from 28 - 30 November 2016, with support from ASEAN NCAP, Stop the Crash took place at Sepang International Circuit. The event consisted of a series of safety demonstration showcasing modern crash prevention technologies in action and how they can prevent accidents from occurring in the first place. The event comprised of demonstration for Electronic Stability Control (ESC), Autonomous Emergency Braking (AEB) City, Pedestrian and Inter Urban, Blind Spot Monitoring and tyre safety demonstration. 

As someone who put safety first, I recently went to the event on 30th November (Wednesday) to have firsthand experience on these newfangled safety technologies. Things weren't rosy as I had no clue of the exact location of the event. Thankfully a friendly security guard pointed me to the paddock. And paddock it was! For a moment, I felt like an upcoming F1 superstar ambling around the pit lane vicinity.      

Ok, I digress. The whole point I came to this event was to experience the demonstration of crash prevention technologies - ESC, AEB, Blind Spot Monitoring and tyre safety in action. With that said, let's get to the thick of the action shall we?

Electronic Stability Control (ESC)

Imagine in this hypothetical example: You're trundling along the highway. You're cruising at say 80 kph. Suddenly, a crate came rolling into your path. Your instinct went into overdrive, so you swerve your car to one side, hoping to avoid the crate. When you think the danger is over, a huge rock stood in your escape route. You instinctively swerve to one side, only this time the car became wildly out of control and spun around like a doughnut. You became a mere passenger, unable to stop the car from spinning around. 

This is where Electronic Stability Control (ESC) will come in handy. Applying ESC to the same hypothetical example above, you would have easily avoided hitting the 2 obstacles without spinning out, as ESC will pull your car back in your intended direction. With ESC, you'll be able to:

• retain control during emergency manoeuvre (car remains stable and straight).
• increase confidence in handling emergency situation.
• keep yourself, your passengers and fellow motorists safe.

ESC works by applying selective braking to the appropriate wheel (say braking the front left will stabilise the car, ESC will apply the front left brake as an example). The image above shows the sensors that work with ESC. 

The one called 'yaw rate sensor' monitors the side-to-side motion (when the car turns left or right so to speak), while the 'steering angle sensor' measures how far the driver has turned the steering. 

These sensors will compare each other's readings and if any deviation is detected (say the car turns too far right with minimal steering input), the ESC computer will select the most appropriate wheel to brake and prevent you from rolling upside down, knock down your GF's gate or fall off the cliff.

The video below (recorded by me) will demonstrate the car's behaviour during emergency manoeuvre, with ESC on. The car was driven up to somewhere between 70-80 kph.

As you can see from the video above, the car still points 'straight' (doesn't spin out) even when the demonstrator abruptly yank the steering one way the other. Watch the video below (ESC off) and you will see the difference ESC makes. The car was again driven up to 70-80 kph.

  

   

With ESC off, the car spins around, facing the wrong direction as depicted in the video above. 

The demonstrator later told me ESC is only as good as the tyres, so if you have 4 bald tyres, you might as well throw away the ESC.  

Despite that, after experiencing the effectiveness of ESC in preventing skidding, I can't think of a reason not to have ESC. Thank god Malaysian government has made ESC mandatory on all new cars sold in Malaysia by June 2018.

Autonomous Emergency Braking (AEB) City, Pedestrian and Inter Urban

If you've been keeping abreast with the automotive news, you may have come across the term Autonomous Emergency Braking or AEB. In case if you've no idea what it is, let me fill you in.

AEB is a safety feature that prevents you from hitting a vehicle or pedestrian by automatically applying the brakes. Yep, it actually brakes for you, handy when you fail to spot a car in front of you has stopped or a child has carelessly crossed in front of you, due to exhaustion after a hard day at work. Of course, this is by no means an excuse for distracted driving. As a driver, it is important that you pay full attention behind the wheel and not be complacent.  

So how does it work? AEB relies on camera and array of sensors to detect obstacles such as a pedestrian, a car, etc. If it detects collision with the obstacles exemplified are imminent, the system will initially issue audible warning to the driver to take action (your car will make a beep beep beep sound or a long chime depending on manufacturers). If the driver doesn't take action, the system will automatically apply the brakes, even when the driver fails to physically hit the brake pedal. Accident averted, ladies and gentlemen👍

At the event, the AEB demonstration was divided into 3 sections: (1) City (approaching a stationary dummy car), (2) Pedestrian (a dummy carelessly crossed the road), and (3) Inter Urban (approaching a slow moving dummy car). In all 3 demo, the demonstrators never physically applied the brake pedal even after the car warned them to brake. In the video below (recorded by me), you can hear the warning sound, followed by braking action, which was done by the car, not by the demonstrator.

But, here's one big BUT. The demonstrator told me the moment your car is FULLY stopped, you MUST take control of the brake pedal or your car will roll forward and BAM whatever obstacles standing in your way. 

Also, the AEB has a prescribed maximum allowable speed range it will function. Exceed the range and the system will not work. In the case of the Volvo (I forgot the model name) I sat in for AEB City, the demonstrator said its AEB will function only up to 50 kph. Above 50 kph and you're on your own (you've been warned). I believe the speed range is manufacturer specific, so do ask the car dealer on your specific car's AEB speed range if your new car does come with AEB. 

Blind Spot Monitoring

You're cruising down, say, a two-lane road. You decided to switch lane. You've checked your mirror. All clear. So you assume it's safe to make a lane switch. As you're making the switch, suddenly you're greeted by a honk. You glanced over your shoulder and realised somebody was alongside you, eventhough your mirror suggested the coast is clear.

That folks is a classic example on why it is important to check your blind spot before you change lane. You've probably been through this experience, where a clueless motorist change lane and nearly side-swipe you. Checking your blind spot can help reduce your chances of getting into an accident, as this too has helped me stay safe on the road.

In a bid to reduce the likelihood of accident caused by neglecting or forgetting to check the blind spot, manufacturers are increasing the fitment of Blind Spot Monitoring system.

The system monitors for any objects, such as cars, motorcycles, and cyclists, lurking in your blind spot. This is made possible by, as mentioned by the demonstrator, 2 sensors located behind the front bumper, 1 on the right side and 1 on the left side.

Should there be anything caught in your blind spot, the sensors will inform the control unit, which then lights up an icon on the side view mirror where the blind spot falls (if say a car falls in your left side blind spot, the icon will light up on the left side view mirror).

Do watch the video below to see the system in action. I recommend viewing in full-screen for optimum viewing quality.

  

Tyre Safety

What a way to wrap up this post with the most important, yet the most taken for granted safety aspect of an automobile - tyres. It doesn't matter if your car spells B.U.G.A.T.T.I V.E.Y.R.O.N, nor does it matter if your engine makes 5000 horsepower, none of that matters if your tyres are not performing at its best. Think about this: Your car's only mean of contact with the road is none other than the 4 black, oversized-rubber doughnut. 

For this segment, participants were exposed to the effect of improper inflation pressure. The cars used for the demonstration were 2 identical BMW 3 series. The difference was one had all 4 tyres properly inflated (2.4 bar front and rear), while the other one had lower rear inflation pressure (2.4 bar front and 1.4 bar rear).

The purpose of the demo was to show how inflation pressure can affect the car's handling characteristic during an emergency manoeuvre, such as high speed evasive manoeuvre. 

For the purpose of the demo, the demonstrator would drive up to 60 kph towards a bunch of cones, then abruptly yank the steering one way the other to simulate a high speed evasive manoeuvre.

I, together with 2 other participants, first boarded the Bimmer with all 4 properly inflated tyres. What we observed were the car felt 'composed' and 'stable' during the manoeuvre. It's as if the tyres were firmly planted to the tarmac that the car just glide its way through without any fuss.

Then, we boarded the same Bimmer, but with lower rear inflation pressure. It was obvious from our observation this will have detrimental effect to the car's handling, as the car's back end started to 'drift out'.

This shows that we should not underestimate the role that tyre pressure plays in keeping your car safely planted to the road so that you can reach your kampung in one piece.

Now I am done rambling about why tyre pressure is important to safety, now let's take a look at when to check tyre pressure and the tools needed to check tyre pressure:

1. Check your tyre pressure before you begin driving. If you need to check the pressure after driving, do wait for roughly around 6 hours to let the tyres cool down. Why? As you're driving along, the heat generated by the tyres rubbing against the road surface will heat up the tyres, thus increasing its pressure. I've checked my tyre pressure before and after driving and it does increase.
2. Buy either a digital tyre pressure gauge or a simpler pencil-type pressure gauge from any D.I.Y store. The pencil-type gauge looks something like this:

In case if you're wondering, I did record the demo, but after reviewing the video, it's hard to see the difference just by watching the video. You had to sit in the car during the demo (like I did) to really feel the effect. 

I hope this post has enlightened you on the advancement in automotive crash prevention technology. Do give a thumbs up in the comment section below if you have learnt something new!

    

Having problems with evasive maneuver? Ford's Evasive Steering Assist got you covered

The odds of surviving an accident in modern cars are getting increasingly likely thanks to the fitment of safety features, such as Automated Emergency Braking (AEB), Electronic Stability Control (ESC), Traction Control System (TCS), Anti-lock Braking System (ABS), airbags and many more. Well, Ford has decided to add another feature to the list of safety features, the Evasive Steering Assist (ESA).

Imagine you are dawdling around minding your own business when out of nowhere, say a crate, rolled into your path. Assuming you have AEB, the car will automatically slam on the brake to avoid collision. But, what if braking alone is not enough to avert disaster? Naturally you will jerk the steering to one side to steer around the obstacle, but what if you are not applying the right amount of steering to avoid the obstacle? This is where Ford's ESA can lend a helping hand.

Ford's ESA acts as a second pair of hand in case if the AEB could not prevent fender-bender alone. Just like AEB, ESA also relies on camera and radar system to determine if you are performing an evasive maneuver (ESA only kicks in during evasive maneuver, not before), and if necessary, speed up steering response to increase your chances of a successful evasive maneuver. Think of it like an invisible hand magically boosting the steering's response for a quicker evasion.

If you need more details on Ford's ESA, do watch the video below.

Video Credit: Ford Media

Nissan Tsuru discontinued; zero-rated NCAP safety rating

Source: https://en.wikipedia.org/wiki/Nissan_Sentra#B11_.281982.E2.80.931986.29

Safety first folks! Nissan has decided to pull the plug on their Mexican-market Tsuru sedan (otherwise known as the B13 Sentra) by May 2017 due to its dismal zero-rated NCAP safety rating.

Global NCAP and Latin NCAP conducted a car-to-car crash test between the Tsuru and the five-star rated 2016 Nissan Versa (known as Almera in Malaysia). The result of the test revealed the squalid protection offered by the Tsuru.

A 50 percent overlap crash test revealed the Tsuru's main structure failed to absorb the impact, resulting in the driver's head hitting the steering wheel as shown in the video above. Global NCAP posited the driver of the Tsuru could easily suffer life-threatening injuries in an actual road accident. To compound matters, the Tsuru is not equipped with airbag.

Global NCAP secretary-general, David Ward, stressed on the importance of meeting minimum crash test standard to prevent sales of unsafe cars, "Our first ever car-to-car test clearly shows the importance of minimum crash test regulations. Mexico doesn't yet apply them and the US has had them for decades. The lack of standards can result in the sale of unsafe cars like the Nissan Tsuru".

Meanwhile, Latin NCAP reported on this April that the Tsuru was responsible for more than 4000 deaths on Mexican roads between 2007 and 2012.

Video Credit: Insurance Institute for Highway Safety (IIHS)

Brake Override System

Source: http://www.nissanusa.com/blog/brake-override-system

You have just bought yourself a brand spanking new car. You flip through its specification and inevitably come across the term Brake Override System. Wondering what it means? Wonder no more.

Brake Override System is a safety feature that allows the ability to stop a car even with the accelerator pedal depressed at the same time with the brake application.

Why such feature is introduced on modern cars? One notable example that became fodder to the system's introduction is the fatal crash involving Mark Saylor, a California Highway Patrol officer, and his family, when the accelerator pedal of their Lexus sedan became stuck, leading to a deadly runaway car. Investigators blamed the accident on ill-designed floor mat that obstruct the accelerator's movement, meaning the risk of the accelerator not fully releasing is hazardously high. In light of the accident, National Highway Traffic Safety Administration (NHTSA), an executive branch of the US government under the Department of Transportation, has mandated the system to be implemented by every manufacturers in a bid to protect vehicle occupants in an event of stuck accelerator pedal.

Source: http://brainonboard.ca/safety_features/active_safety_features_brake_override.php

How does it work? When the system detects that both pedals are depressed at the same time, it gives the brake more precedence. In a nutshell,even with the accelerator depressed, the system will make it feel like the accelerator is fully released, enabling your brake to slow the car down effectively. This should in theory prevents you from roaring down the highway with a death note sticking on your forehead.

Should this system be featured on every new cars? Like every safety features, one must know how to use it and remain responsible on the road. It is not a great idea to fall into a false sense of security thinking you can drive around like you are in Too Fast Too Furious movie scene. Nevertheless, any features with life-saving potential make great sense as an extra protection to keep you out from a wreck.