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Japan plans real-world diesel emissions test after companies fail

Japan's transport ministry plans to start real-world diesel emissions tests after an experiment found four models from Toyota, Nissan, and Mitsubishi that produced more nitrogen oxide (NOx) emissions than the nation's rules allow, according to The Japan Times. Regulators there usually only perform emissions checks in the lab. The VW diesel scandal has everyone double-checking their figures. Diesel versions of the Toyota Hiace van, Land Cruiser Prado, and Nissan X-Trail produced up to 10 times more NOx than allowed. The Mitsubishi Delica D:5 was up to five times over the limit, The Wall Street Journal reports. There was no evidence of defeat devices in the vehicles. Mazda performed well in the experiment, though. The CX-5 passed with nearly the same results on the road and in the lab. The Demio, better known as the Mazda2, did nearly as well with only slighter higher figures in the real world than in the controlled setting. The experimenters theorized the reason for the excessive emissions was that cold weather caused the engines' software to shut off the exhaust gas recirculation to prevent damage, according to the WSJ. However, this behavior also increased NOx production. Toyota, Nissan, and Mitsubishi don't have to worry about punishment from the transport ministry because this check was just an experiment. Their models already passed the mandated lab tests, which was the only requirement, according to The Japan Times. As governments begin greater real-world emissions tests, the results suggests diesels aren't very clean. A recent check in France found models from Ford, Renault, and Mercedes-Benz that didn't perform up to the standards. Regulators in India conducted similar evaluations and ordered VW to recall over 300,000 vehicles. Related Video:

Toyota develops new pre-collision system with steering assist

A number of automakers are working on developing fully autonomous cars, but it looks like the groundwork for such technologies will likely show up first as semi-autonomous systems for both safety and convenience. Following recent announcements from Nissan and Ford in this area, Toyota has now released information for some of its advanced semi-autonomous technologies that could be offered in production cars over the next few years.
On the safety front, Toyota's new pre-collision system with pedestrian-avoidance steering assist is aimed at protecting the folks who aren't in the car. This system combines visual and audible alerts with automatic brake assist and automatic steering. If warnings don't get the driver to slow down, the brake assist kicks in if a collision is very likely, but if that is still not able to avoid the impending collision (and if there is enough room to do so), the car can automatically steer itself around the pedestrian. This sounds most beneficial for last-second dangers such as a person accidently stepping out into the road in front of a car. Toyota hopes to have this technology available to customers by 2015.
The Japanese automaker is also testing a suite of technologies called Automated Highway Driving Assist (AHDA). The key part of this is a new adaptive cruise control system that uses vehicle-to-vehicle (V2V) communications rather than a radar-based system. This cooperative-adaptive cruise control allows vehicles to communicate their acceleration and deceleration data with other cars, which Toyota says this helps to improve fuel efficiency and traffic flow. Also a part of AHDA is the Lane Trace Control feature, which sounds like a next-gen lane keep assist. This system uses cameras, radar and a computer to keep the vehicle in a "smooth driving line" by being able to change steering angle, engine torque and braking force. Toyota says this technology could be in place by the "mid-2010s."

Toyota to buck engine downsizing trend, may go larger and turbo-free

Turbocharging isn't really Toyota's specialty, and the Japanese automaker isn't being shy about acknowledging it. Koei Saga, a senior managing officer in charge of drivetrain research and development, says that eschewing turbos and increasing displacement of engines using the Atkinson cycle can produce better power gains without sacrificing fuel economy, Automotive News reports.
Toyota is investing heavily in larger-displacement Atkinson-cycle engines in addition to turbocharged engines, but Saga doesn't think the automaker will use turbocharging across many product lines. He apparently remains unconvinced that the technology "makes the world better."
In Toyota's eyes then, Atkinson cycle engines do make the world better, and here's how. Their pistons complete four processes - intake, compression, power and exhaust - in one revolution of the crankshaft, and the power stroke is longer than the compression stroke. Traditional Otto cycle engines require two crankshaft revolutions to accomplish those same four operations and have equal-length compression and power strokes. Atkinson cycle engines are more efficient, but less power dense, though increasing displacement can offset that shortfall.