The Implications of BMW’s New Tech

Now, much derision has been made about the use of driver aids from a purist approach, but in retrospect and with a touch of eye-opening from BMW’s South African bigwigs, one can see their importance. You could say that I may have eventually been swayed; or you could say one can only stay resistant to change for so long. Adapt or die.

Lane Keep Assist/Lane Change Warning System & Radar-guided Cruise Control

This lane maintenance system may have a variety of labels and slight variations in how it works but the essence is the same: it helps the driver maintain his lane on the motorways. In some cases, the car will steer itself back in line should it stray over the markings, or in a case like the new 5 Series, the steering will vibrate and keep buzzing until you stop stepping on the line.

This looks like promoting laziness or ineptitude on the driver’s part, letting the car almost drive itself; because if you combine radar-guided cruise control and Lane-Keep Assist, you essentially have a car that is damn near sentient in traffic. Well, not quite…

First off, these are not self-driving (fully autonomous) cars as we have come to know them in recent times, so that means there is only so much the car will do for you. Several times the car will remind you to keep your hands on the wheel via a series of optical warnings. The radar will also warn of looming calamity via aural and visual admonition before intervening on your behalf. These can become an annoyance after a few instances, not to mention the buzzing steering wheel. So what is the outcome of all this?

The opposite of what people believe, that’s what. You become a better driver. Listen here. The constant warning lights, beeps and thrums can get old really fast after which they degenerate into a legitimate irritation. You could summon some silence but raise your driving risk factor by shutting them off where possible, or alternatively, you could increase the peace by just driving better. Stick within the lines. Maintain your following distance. Pay attention to your blind spots. Modulate your throttle inputs to prevent wheelspin (and the attendant traction control warning light/beep). Just drive as well as your parents did back in the day when the only electricity running through the car was channeled from the battery to the headlamps and “early warning systems” involved terrified passengers/pedestrians screaming at you about how threatened they felt by your inattention to your surroundings. Follow?

So, the tech benefit is two-pronged: first it keeps you safe. Second, it makes you a better driver by being belligerent when you aren’t. We may not all want this kind of help but eventually we will all need it. Traffic density has been increasing exponentially over the past three decades, which makes driving now a lot trickier than it was in our fathers’ times. The road network is becoming wider and more elaborate, just keeping track of where you are and the path you need to take without begging the woman living in the dashboard for help calls for mental engagement not unlike attending a math class. Car design is evolving to a point where external all-round visibility has to be compromised in a nod to safety, as was seen with the G30’s A pillars. There is only so much you can do to stay off the guardrails and/or the next guy’s fenders before finally admitting that yes, perhaps that blind spot warning system is an actual real lifesaver and not yet more evidence of the wussification of the millennial demographic.

The importance of economy driving

The X6M50d had a fancy techno-whizz instrument cluster that showed many things as mentioned last week, and one of them was the battery charging meter. It kind of works like a video game and goes like this:

In Eco mode, the dash clocks have blue outlines with white markings. The aim here is to get a green tint somewhere (you win!!), and there is a trick to achieving this. Start by taking your foot off the throttle. You are halfway there, as the meter now shows zero. To get green, brake ever so slightly, and the meter goes into the positive: your battery is now charging via regenerative braking, like a Formula One car’s KERS (Kinetic Energy Recovery System). Yippee!!

This may at first glance seem like a counterproductive approach to economy driving (whereby minimal braking is a key technique), but hold that thought.

[“Hear that, Mr. Anderson? That is the sound of inevitability” -Agent Smith, The Matrix]

By asking you to charge your battery by braking, BMW is trying to prepare you for the future; and the future is upon us.

I did say that the X5 XDrive40e borrows tech from the BMW i8 hybrid supercar, right? Hybrid tech is the future; be it the Henrik Fisker/James May method of using the internal combustion engine as an onboard generator for the electric motors that drive the wheels, or using both the engine and the electric motors as means of propulsion either alternatively or concurrently (a la McLaren P1).

On paper, it might be easy to suggest otherwise or criticize. Case in point: that same XDrive40e. It has an internal combustion engine. Why not use that as both propulsion and as a generator when the car’s batteries run out? Charging the car while parked (e.g. overnight) may be convenient most of the time but is not always practical, especially in a country with a shaky power grid such as ours; and “regular” cars do charge their accumulators while on the move, don’t they?

It may not be that simple or straightforward from an engineering point of view; just the same way there are cars that run both petrol and diesel in the same engine (see the M35 Deuce-And-A-Half), it’s not that obvious putting this technology into everyday use. The best compromise scientifically is an energy recovery system, which is what KERS is.

The physics concept behind KERS is to get as close to a perpetual motion machine as possible. The energy spent accelerating the car (electrical or chemical energy converted to kinetic energy) can still be reclaimed to a large degree when slowing down (kinetic energy back to electrical energy) through the use of dynamos attached to the braking system. This minimizes waste, increases efficiency and by making the car close to self-sufficient in energy production and consumption, spares the environment further degradation. It also improves the car’s braking ability by virtue of weight of the dynamos, which in turn means increased life in braking system components such as pads and/or rotors (think of it like the use of engine and exhaust brakes in heavy commercial vehicles).

Hybrid tech is inevitable; eventually everybody will embrace it as crude oil levels continue to dip and when the black stuff eventually peters out, electric cars are going to take over; either way, cars will have batteries from now on; and I’m not talking about the accumulators under the bonnet that we charge using alternators. How those (lithium ion?) batteries are charged may vary but it is fairly obvious that an onboard charging system is far more sensible in the battle against range anxiety than a ship-to-shore cable running from your car to a wall socket. And that is why the X6 I drove encouraged me to brake as much as I could when I could when in Eco Mode. Because KERS is life.

Start-stop technology

I’ve never been a fan of this, for one very simple reason. I may have ties to the automotive aftermarket modifications scene and I know just how important oil pressure and temperature is not only for normal engine operation, but for turbochargers as well (of which I have two). So an engine that cuts out automatically every few seconds really grates on my veins and sends my OCD haywire – I’m from the old school. I warm my engine up in the morning, I don’t shut it down in traffic jams and I have a turbo timer that keeps the motor running long after I have locked the car and entered my house.

I had to ask BMW’s resident geek in Mzansi. Surely all that intermittent starting and stopping cannot be good for the hot, hard life that a turbo lives, can it? Heat dumping and oil coking are just two of the biggest attendant problems of interrupting the sweet lubricating and cooling circulation of synthetic 5w40 by suddenly cutting off the oil pump. There is the battery to think about as well: starting an engine draws a lot of current from the battery and frequent application can easily kill your accumulator long before its due date.

So, it seems somewhere along the way things changed. As explained by the tech guy in George, the lubricating system of these new cars have a one-way (non-return) valve somewhere downstream of the oil pump, which means when the pump goes offline after the engine is shut down, all the oil won’t just trickle back into the sump through gravity. That means when restarting the engine, there will still be oil right where it is needed, within the engine. That also means these cars don’t need that “warm up” period after a cold start like El Turbo does – the oil may not be warm, sure, but it is still in play; unlike our old cars where the warm up may not be literally warming up so much as getting the oil from the sump and into the engine. Think of it as hybridized wet sump-dry sump lubricating system.

This, however, means that the non-return valve leaves stagnant oil within the turbo on engine shut-off, and this is akin to locking the janitor inside a tiger cage as he’s cleaning it while the tiger is asleep. When the tiger wakes up, running will not help the cleanup man; he has nowhere to go, you locked him in, remember? Heat dumping leads to oil coking which in turn leads to a dilemma: immediate service or a ruined engine. What kind of choice is this?

Ah, but you see, the oil’s duties have been relegated strictly to lubrication only. Cooling the turbos is now done by water, not unlike the main cooling system for the engine; and just like the main cooling system, circulation continues (however briefly) even when the engine is off; providing a sufficient enough cool-down/spool-down buffer to prevent killing the tin snail. This should be answer enough to my friends from the Great Run IX who wondered why the Volkswagen Amarok I was driving (and majority of modern cars) does not have a timer installed despite running a heavily boosted diesel engine.

As for the frequent starting, current is rarely drawn from the accumulator itself. There is an array of capacitors that serve this purpose; and capacitors are by definition designed to charge and discharge rapidly, which means they are exactly what you need when drawing large currents in short bursts on a frequent basis.

No further questions, your honor.



One thought on “The Implications of BMW’s New Tech

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.