2011 Cadillac Platinum Collection on 2040-cars

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GM executive chief EV engineer says reducing cost of plug-in vehicles is 'huge priority'

As we know, another major automaker investing heavily in electrified vehicles is General Motors, and it's doing things much differently than rivals BMW, Ford or Nissan. The Chevrolet Volt extended-range EV is a modest seller at its $35,000 sticker price but a huge hit with owners. The Chevy Spark BEV, still in limited availability, puts smiley faces on its owners and drivers. The just-introduced Cadillac ELR, a sharp-looking, fun-driving $76,000 luxocoupe take on the Volt's EREV mechanicals, has admittedly low sales expectations. With this interesting trio in showrooms and much more in the works, the third vehicle electrification leader I collared for an interview at Detroit's North American International Auto Show (see #1 and #2) was Pam Fletcher, GM's executive chief engineer, Electrified Vehicles. ABG: Why do your EREVs need four-cylinder power to extend their range when BMW's i3 makes do with an optional 650 cc two-banger? "We designed [the Volt and the ELR] to go anywhere, any time" - Pam Fletcher PF: I get that question all the time: why not something smaller? You don't really need that much. You use the electric to its ability, then you just need to limp. But we designed those cars to go anywhere, any time, and we don't want their performance to be compromised. If you're driving through the mountains, we don't want you to be crawling up grades, or to be limited on any terrain. So it's optimized to be able to travel literally the biggest grades and mountain roads around the globe at posted speeds. Because what if you can't? Another good reason: when the engine is on, you have to run it wide open throttle, max speed, most of the time. And while we can do a lot with acoustics, and the ELR has active noise cancelation, a small-displacement, low cylinder-count engine at high speed, high load all the time isn't something you want to live with. That's how we came up with the balance we did among the key factors of performance, NVH [noise, vibration and harshness] and range. ABG: Where you go from here? Is the range-extender engine due for an update? PF: We know and love the current Volt, and there is still a lot of acclaim about it, so we think it's a good recipe. But we are heavily in the midst of engineering the next-generation car, which I think everyone will love and be excited about.

Super Cruise’s failsafes

Even though Super Cruise is not a fully autonomous system, it incorporates redundancies like those used in aircraft to ensure failsafe operation. Before taking off on a 700-mile, 11-hour test drive of the system — and putting my life in its hands without my hands on the wheel — I sat down with Daryl Wilson, lead development engineer for Super Cruise, to get a deep dive into the system and its critical safety backups. Autoblog: First, what makes Super Cruise different from similar systems? Wilson: The key differentiator for Super Cruise is hand-free driving. It's an industry first in that respect. Our competitors require the driver at minimum to place their hands on the wheel with some frequency to ensure that the car knows that the driver is there. We don't. Two key technologies allow us to do this. One is our Driver Attention System, which is our methodology for making sure the driver is engaged with the vehicle and engaged with the road. This is a driver assist system, not a fully autonomous system. So it requires driver engagement. We use an infrared camera that constantly monitors the driver's face to determine the direction they're looking. We're looking for the driver to be what we call on-road — not on the center stack, not to left or right or down. That's all done by the tracking of the face. We also track that the eyes are open. It's infrared because at night you need to illuminate the face and you can't be shining a light into the driver's face. Then we have our lidar mapping that provides a foundation for control and redundancy to ensure safe performance. Autoblog: How does the mapping act as a redundant feature? Wilson: This system is only for use on divided, controlled access highways. What I mean by a divided highway is something more than a painted line between you and oncoming traffic. Whether that's a grassy area in between the lanes or a concrete barrier, anything that separates you from oncoming traffic. That's the divided highway part. The controlled access part is entrance ramps and exit ramps. Not with roads that cross at grade, with traffic crossing at the same level. To do that we geofenced these roads to ensure that operation is only allowed in these conditions. We don't just recommend you use it there; we ensure that you only use it there.

How Cadillac improved power output in 2016 ELR by 25 percent

Earlier this year, Cadillac announced that the 2016 ELR would come with a big price drop and a powertrain that packs 25 percent more power output. That's a lot more oomph, but it didn't sound like the Caddy engineers made any major changes to the engine or motors. So, what happened? Let's refresh our memories with the numeric details. The 2016 car is 1.5 seconds quicker to 60 miles per hour than the 2014 model (there was no 2015), down to 6.4 seconds. The 2014 put out 295 pound-feet of torque. For 2016, it will be 373 lb-ft. The specific breakdown of the various components in the powertrain has not been disclosed, but from what we can tell, the two electric motors and the 1.4-liter inline-four engine in the new ELR are not that much different than those in the old one. Sam Abuelsamid, senior research analyst at Navigant Research (and former writer here at Autoblog) said that any of the unspecified upgrades would be difficult to tell on a part-by-part basis, but the overall effect will be noticeable. "The changes to the ELR as I understand them are analogous to getting more performance out of a 1965 Mustang with the entry version of the 289 cubic-inch V8. You can replace the carburetor with a larger version that enables more air and fuel to flow into the engine, thus producing more power. The basic engine hasn't changed, but power capability is being unleashed by feeding it more." "Cadillac has changed components in the power electronics to enable more current flow into the motor and thus produce more torque. When you do this in the Mustang, you probably need to replace the rear axle gears and use a beefier clutch to transmit the power to the wheels. Similarly, the ELR probably has some upgraded clutches, bearings, and gears to withstand the increased total output." Cadillac spokesperson David Caldwell told AutoblogGreen in an email that the new ELR does indeed have more than just new lines of code. "One could not 'reflash' a previous ELR to get the performance of a 2016," Caldwell said. "If one only changed software you would not get the performance upgrade fully, as the 2016 creates higher current, more power. So these have been upgraded physically – hardware.