Spot the Difference?

Did you know that the Renault Koleos is very much a Nissan X-Trail?  Were you also aware that the current BMW 7-Series is the platform for the new Rolls-Royce Dawn?  These days car manufacturers are sharing a lot of the components that go into making a new vehicle.  A lot of the electronic systems and computer chips are shared between makes and models, even engines and an entire body platform.  As the costs of designing and building a complex new car rise, by getting together and pooling money, skills, assets, and sharing the costs of the new build, these are definitely clever ways for manufacturers to reduce their overheads, and the overall cost of designing and building a new vehicle.

Platform sharing between manufacturers and between models is, perhaps, more common than you may have thought; and particularly now more than ever.  In some cases, the similarities between a particular car, truck, or ute and its platform-twin are obvious.  However, at other times it’s not so easy to detect the resemblance.

A car’s platform is the base (including body shell, floor, and even some of the chassis and engine parts) on which it is built.  Not only can these components be common to more than one manufacturer, but they can also be shared between models in a manufacturer’s line-up.  The initial platform design and its production or engineering works can be shared across a number of different models.  Kia and Hyundai are some of the best brands at doing this sort of thing, and so too is VW.

Sharing componentry between different manufacturers/brands has to be built on an existing good business relationship.  So, when two or more automotive manufacturers with a good relationship have shared the same desire to save money, they can operate together and agree to share development costs and also essentially sell the same cars but under different badges.  Renault and Nissan are great examples of this.  Some of the most talked about illustrations of this occurring recently will have been the Toyota GT86 and the Subaru BRZ, which are essentially the same cars tarted up slightly differently.  Also, the Toyota Corolla station wagon and the Suzuki Swace (a less known model here in Australia) are exactly the same car.  Another illustration would be the awesome new Toyota Supra and BMW Z4 cars.  Also, Volvo has platformed shared quite frequently over the years.  The Global C-car Platform from Ford saw the Volvo S40 and V40 share much with the Ford Focus and Mazda 3.  Well known Hyundai and Kia have utilized several duplications of platforms for their small automobile line-up since 1997.

Having a shared engineering platform, where manufacturers build a basic foundation that can be used across many of its own models is an advantage.  The Volkswagen Group (VW), and the brands it owns, (Audi, Bentley, Lamborghini, Porsche, Seat and Skoda) are masters of this craft.  VW has a common practice where they will build a smaller number of platforms, but the benefits come when they will then re-purpose these platforms across their own different brands.  When VW designed and built the MQB (Modularer Querbaukasten) platform, it was shared across the Audi A3, Skoda Octavia, and Seat Leon.  Also, one of its SUV platforms is shared and utilized by the Audi Q7 and Q8, the Bentley Bentayga, the Lamborghini Urus, and Porsche’s Cayenne.

BMW’s 7-Series is the platform for the immensely luxurious and expensive Rolls Royce Dawn.  The new 7-Series is luxurious and sleek in its own right, but it is also much, much cheaper to buy – comparatively.

Some other new vehicles that are currently sharing platforms:

Cadillac CTS and Chevrolet Camaro

VW Polo and Skoda Scala

Mercedes Benz GLE and Jeep Grand Cherokee

Renault Koleos and Nissan X-Trail

Fiat 500 X and Jeep Renegade

Terramechanics: The Science Of Off-Roading

A lot of us have purchased, or have considered purchasing, a 4×4 vehicle. This could be because we like the benefits of extra safety or the visibility of the higher body. Or it could be that we want to go off-road in the vehicle and do a spot of exploring. However, when we get behind the wheel of one of these vehicles and head for the nearest dirt road or river, we don’t often stop to think about all the science behind what we’re about to do. The most we might think about are things like the power and torque needed – and possibly the basic physics involved in getting over or around a gnarly bit of terrain.

However, there’s a whole branch of science related to off-road driving, known as terramechanics. In fact, there’s a specialised scientific journal on the topic. Terramechanics has been a scientific topic since the 1950s, and the concept was introduced by a Polish-born engineer by the name of Dr Bekker, who was one of the key developers of the lunar rover vehicle used on the moon. However, much of Dr Bekker’s work was more down to earth – literally.

Terramechanics, in a nutshell, is the science of how a vehicle operates off-road on rough, uneven and soft terrain. It mostly considers the interaction between the wheels and the ground, although the science also acknowledges that things like the length of the wheelbase, the torque and the ground clearance are all very important factors. However, it’s what happens where the rubber meets the (off) road that gets certain people in white coats (probably dirty white coats) very excited.

Now, if you get right into terramechanics, the maths gets pretty complicated. If you’re like me, you probably left quadratic equations behind once you left high school. However, engineers and designers in the field of terramechanics use them all the time. I won’t get into the heavy-duty maths, but here, we’ll have a little look at some of the things that get thought of when the designers are coming up not just with new 4×4 models but also with the tyres that go on them.

Vehicle-related factors

Load: the weight of the vehicle plus what’s in it – probably you, a friend, the dog and something to eat.

Contact area: Exactly how much of the tyre is touching the ground. This is affected by the design of the tyre, the width of the tyre, how much air you put in the tyre and the condition of the tread.

Rolling resistance: Also known as friction.

Torque: You knew this one was going to be important, didn’t you? That’s why the torque – the measure of rotational acceleration (rather than linear acceleration) is always given in the specs of any vehicle.

Wheel width: Put simply, more contact area means more grip.

Wheel radius: There’s a reason why 4x4s have bigger tyres, and it’s not just for better ground clearance.

Terrain-related factors

Designers have to consider these factors when they design tyres and the vehicles. As anybody who’s done any off-roading will know, not all types of terrain are created equal, and the techniques and tyres that work well with, say, snow won’t work with sand.

In fact, a lot of what goes on in terramechanics considers the properties of the soil or the other terrain (snow and sand). You might think of soil as just mud or good plain dirt, but it’s pretty complicated stuff. It’s a combination of solids (the actual particles of soil), liquids (water) and gases (air), and it’s constantly changing even in a single place, to say nothing of how soil varies from place to place. I won’t bore you with all the different factors, what they mean and how they affect each other, but some of the most important ones that researchers have to specify when they run tests of new tyre designs or even whole cars are the following:

Moisture content: How much water is in the soil at any point. This affects the shear strength of the soil, which is very important in a lot of the formulae used in terramechanics to work out whether a wheel will lose traction or not. The shear strength of anything is its ability to stand up to a force that will make it slip sideways.

Porosity: How much air is inside the soil – these pores are where the water goes when you water the garden.

Particle size and shape: How big the minute particles of soil are and what shape they are has a big influence on how the dirt sticks together, holds moisture and compacts under pressure. Most of us have known since childhood that sand and clay are very different, and this difference is mostly down to particle size and shape.

Specific gravity: How dense a substance is. Yes, this is related to the specific gravity known to home brewing enthusiasts.

After considering these basic factors, things start involving complicated equations that make my head ache.

You know, I’m kind of glad that when I go off-road driving, I don’t have to keep all these factors and the science in my head – otherwise, I’d overthink everything all the time and wouldn’t enjoy the experience. An experienced off-road driver will be able to do by feel and “instinct” (i.e. right-brain thinking) what the terramechanics expert would have to calculate. All the same, I’m glad that there are people working hard to make sure that our vehicles and the tyres on them are the safest and best they can be.

Boom Times for Catalytic Converters

In recent times, the humble catalytic converter has become a hot commodity. And no, not among car enthusiasts, even though it plays a vital role in your car, but among thieves. Crime involving the theft of catalytic converters has soared and it is not without reason.

What is a catalytic converter?

Located between the engine and the exhaust on the underside of your car, the catalytic converter has a very important role to play. It is responsible for converting toxic gases and pollutants such as nitrogen oxide and carbon monoxide, which are emitted exhaust gas within an internal combustion or diesel engine, into less harmful pollutants.

Featuring for the first time in vehicles back in the 1970s, catalytic converters have played a monumental role in reducing our footprint on the environment. It is estimated that catalytic converters have reduced certain emissions by upwards of 80%.

However, despite their utility on cars, thieves have their eyes on catalytic converters for different reasons.

A prime target among thieves

Although it might seem as though the theft of catalytic converters is a newfound phenomenon, it’s really not. In fact, this has been going on for as long as they’ve been found on cars.

However, data out of the US from recent years points to skyrocketing rates of theft involving catalytic converters. In 2008, there were an average of just 108 reported thefts of catalytic converters per month. Fast forward to 2020, the rate had leapt to more than 1,200 per month.

Why are catalytic converters being targeted?

What’s driving the surge in crime you might ask? It all comes down to the valuable parts metals found within the assembly of a catalytic converter. In particular, trace amounts of the precious metals in platinum, rhodium and palladium are found within a ceramic part inside catalytic converters.

In the midst of the transition towards electric vehicles, demand for these elements has ballooned to new heights. That’s because electric vehicles incorporate these minerals in battery development, alongside others like lithium, cobalt and nickel. In response, prices for these metals have taken off, each recording exponential growth after a long period of stable pricing.

In addition, supply of these metals was impacted over the pandemic, leading to pent-up demand. These minerals are largely derived from the likes of South Africa, and while they have long been available quite readily, that changed when mining activities were shut down for months on end last year. With demand increasing not just on the back of EV development, but also natural growth in the catalytic converter market as Europe and Asia push harder emissions standards, an imbalance in the minerals market has caught many out.

With the prospect of a second-hand converter being scrapped for hundreds of dollars in the black market, and then being on-sold for an even greater sum once the minerals are extracted and sold back to car manufacturers, it’s a loop that shows no sign of closing. It’s a good reminder that you should always keep in mind car safety, and fortunately, a growing number of anti-theft devices now cater to combatting this worrying trend.

How Much is Too Much for EV Driving Range?

How long should an EV be able to travel on a full battery?  ‘Neue Klasse’, from BMW, suggests that 1000 kilometres is about right.  BMW’s New Class of vehicles are not far off the runway now, said to be arriving in 2025.  And they are going to be the first BMWs-ever that have been designed from the ground up to be specifically all-electric, EV through-and-through.

That does raise an interesting question: How far should we expect our brand spanking new EVs to go on a full charge (a full tank of electrons instead of a full tank of gas)?  Should we be able to drive from Sydney to Melbourne (877 km), Sydney to Adelaide (1374 km), Sydney to Cairns (2430 km), Sydney to Perth (3932 km), or just Sydney to Wollongong and back (about 175 km) on a full battery?

Most of us are probably sick of driving non-stop after 6–8 hours max in a day.  So, say most of that was done at 100 km/h, then 100 × 8 hours would get you to 800 kilometres before you’d be needing a proper cup of coffee in a proper coffee cup!  It would be then you’d want a rest and a sleep, right?

Perhaps Neue Klasse has got it bang on then.  1000 km would cover an all day blast up the coast from Sydney to Brisbane, which is approximately a total of 911 kilometres via the coastal route.  Get to the end of that journey, and you could pull up at a mate’s place for tea, or a motel, and plug in your EV overnight ready for the long drive back home.

According to Thomas Albrecht (BMW’s head of Efficient Dynamics), in 2025, New Class EV BMWs are set to have “thirty-percent or more” range than what’s currently available now.  That means that the brand-new BMW EV platform with lots of fresh pieces of technology, including 46 mm cylindrical battery cells, should push the Generation 6 batteries out to around 1000 km before they run out of electron juice.  Even though BMW could go further than this 1000 kilometre range, Albrecht suggested that this would be the maximum that BMW will offer because they don’t think that such a long range is necessary.

BMW will debut the new Generation 6 batteries in the 2025 BMW 3 Series EV.  How much do you think we should be able to get out of the battery packs in any new EV bought in 2025–2030?  I’d be interested to know – remembering that battery tech and recharging times will likely have vastly improved by then.