[car home Technology] Cadillac XTS is here. Believe it or not, this time, it seriously sent an afternoon letter to Audi A6L. It is natural to be prepared for such a high profile.
● engine
◆ 2.0T engine
Cadillac XTS models sold in China will provide two choices: 2.0T engine and 3.6L naturally aspirated engine. From the product information (2.0T Elite, 2.0T Luxury, 2.0T Premium, 3.6L Platinum), models equipped with 2.0T engines will become the main sales force. Can this 2.0T engine with the title of Ward’s Top Ten Engine provoke this girder? Let’s take a look at it.
276 HP (203 kW) /5500rpm
(269 HP /5300rpm in China)
(355 Nm /2000-5300rpm in China)
This LTG 2.0T engine is very dazzling in terms of data. Even for the models listed in China, after localization adjustment, the 2.0T engine still retains 267 horsepower, which is not easy for a production car.
In fact, these technologies are not enough to make this 2.0T engine stand out among all sentient beings. Only data can explain its power. EA113 engine (mounted on Audi TTS) with the same level is obviously not as trendy as LTG engine, while Mercedes-Benz, BMW and other similar products are technologically advanced, but they have no courage to push the data to a higher level. I think this is the value of the 2.0T engine code-named LTG. According to GM staff, this engine will become exclusive to Cadillac brand in China market.
◆ 3.6-liter naturally aspirated engine
Among the four models, except for three models with 2.0T engines, Cadillac XTS also provides a model with a 3.6-liter naturally aspirated engine. Judging from the type of engine, this engine obviously pays more attention to the more linear power output.
(309 HP /6700rpm in China)
(360 Nm /5400rpm in China)
From the parameter point of view, compared with the cylinder diameter, the shorter stroke makes the engine better at running at high speed, which is beneficial to the transmission of power in a more linear way. Although the efficiency is not as good as that of the 2.0T engine, the engine is more in line with the positioning of Cadillac XTS in terms of working characteristics.
In terms of engine technology application, this LFX model 3.6-liter naturally aspirated engine can also be called the mainstream. The addition of in-cylinder direct injection system can get a larger compression ratio for the engine, so as to improve the working efficiency of the engine. In the traditional sense, the V6 engine has stronger power and smoother operation, but the problem of self-weight is always an unavoidable disadvantage. However, with the improvement of engine manufacturing technology, the engine weight can also be controlled by using more integrated components, and so is this V6 engine. The weight of 157kg relieves the pressure of the front suspension to a certain extent, and the handling performance will benefit.
◆ The naming rules of the rear logo have changed.
● base
There are also some bright spots in the suspension structure of Cadillac XTS, such as Hiberstrut front suspension structure evolved from McPherson structure and the combination of MRC active electromagnetic induction suspension system and rear axle air spring. These chassis technologies really add a lot of color to Cadillac XTS. It is worth mentioning that although the models to be sold in China are not equipped with four-wheel drive systems for consumers like the overseas models, we also have reason to look forward to its arrival.
◆ Hiberstrut front suspension structure
Hiberstrut’s front suspension structure evolved from the widely used McPherson style. Compared with the front suspension with double wishbone structure, the traditional McPherson front suspension has the advantages of compact structure, lighter weight and faster response speed in handling. However, due to the lack of sufficient lateral positioning parts, the lateral rigidity is low and the handling stability is poor. In addition, the traditional McPherson structure can not play a good role in restraining the torsion steering caused by unequal length semi-shafts. The structure of Hiberstrut well neutralizes the advantages of McPherson structure and double wishbone structure, that is, it controls the weight and improves the stability of handling.
From this comparison, we can see the difference between the Hiberstrut structure and the traditional McPherson structure. On the basis of the McPherson structure, there is an additional fixed point between the steering knuckle and the steering column, and a short control arm is responsible for the lateral positioning at the upper end. This design concept is similar to that of the double wishbone, except that the structure is more compact and the weight is lighter. In addition to strengthening the fixing rigidity, different steering knuckle fixing methods lead to the change of the kingpin inclination angle, and the smaller kingpin inclination angle makes the wheels of the vehicle have better fit with the ground when turning, thus improving the handling performance of the vehicle in corners. The reduction of the kingpin inclination angle also affects the alignment performance of the wheel to a certain extent, and of course, it can be improved by matching with the steering assist system.
Not only the structure is simplified, but also the front suspension of Cadillac XTS is made of aluminum, such as the bearing seat and the strut at the lower part of the shock absorber.
◆ Brembo four-piston calipers are standard for all front brakes.
Brembo four-piston calipers are the standard configuration of all Cadillac XTS models. Compared with competing models of the same class, this performance-oriented configuration is really rare.
◆ Adaptive chassis
In addition to structural optimization, Cadillac XTS is also equipped with a set of MRC active electromagnetic induction suspension system in the chassis, which can adjust the damping of shock absorber in real time according to the driving mode options and actual driving needs. Not only that, the air spring also appears in the rear suspension part. However, these configurations will only be available in 2.0T premium models and 3.6L Platinum models with 3.6L engines.
The piston rod of the shock absorber is equipped with an electromagnetic coil, and the magnetic fluid in the shock absorber is a suspension liquid in which magnetizable soft iron particles are suspended in hydrocarbon solution. When the electromagnetic coil is energized, the magnetic field formed makes the iron particles form a fiber structure arrangement along the fluid direction, and the strength of the combination between particles in the structure is proportional to the strength of the magnetic field, so the damping performance can be changed only by changing the current.
The system collects information at a frequency of 1000 times per second and reacts quickly, so as to ensure that some unnecessary sloshing is filtered when the vehicle is driving on complex roads, so that the shift of the center of gravity of the vehicle body and the degree of pitching forward and backward can be effectively controlled, and the contact between the tire and the ground can be increased as much as possible. This control logic is also useful in the process of intense driving and after making emergency avoidance actions.
Different from the combination of spiral spring and variable damping shock absorber used in the front damping mechanism, the air spring is selected as the elastic element of the suspension in the rear damping mechanism of Cadillac XTS. I think this is also due to the consideration of ride comfort. After all, XTS has locked in the field of executive cars, and the ride feeling in the back row should be taken seriously. Of course, the coordination of air spring and variable damping shock absorber is also very direct for the control of body posture. In addition, it is also an advantage to adjust the horizontal position of the car body in real time according to the changes of the car body load and road conditions.
● safe practice
The ESS enhanced safety strategy built on Cadillac XTS has attracted many technologies to improve driving safety, most of which are active safety technologies. Of course, passive safety technologies are also superior in the same class cars. It must be mentioned that Cadillac XTS comes standard with 10 airbags.
◆ Active safety technology
Forward collision warning+road deviation warning
We are familiar with these two technologies, which were introduced in detail in "The Third Eye to Analyze the The Secret Behind of the Central Rearview Mirror". Indeed, the best way to improve driving safety is to nip the collision accident in the cradle, and effective monitoring is the key.
The camera installed on the front windshield can take 12 high-definition photos every second, and the image information is analyzed by image comparison software to confirm the real-time situation before getting off the bus in driving state. When it is found that the vehicle is too close to the vehicle in front or the vehicle tends to deviate from the lane, the system can use the indicator light, buzzer and seat with vibration warning function to send a warning to the driver in an effort to make the driver pay more attention. Unfortunately, these two active safety systems only have prompt function at present. It is worth noting that these two functions will be activated only when the vehicle speed reaches the working conditions of the system.
It is not Cadillac’s initiative to remind drivers by vibration. We have introduced the steering wheel vibration reminder in related articles before, and Citroen C6 also uses seat vibration to remind drivers. However, in contrast, XTS’s vibrating seat is more comprehensive in mode, and the vibration can appear in the left rear, right rear or both sides of the cushion, and the vibration in different positions represents warnings from different directions. Cadillac engineers believe that this reminder with direction indication is more effective than the traditional buzzer.
● Man-machine interaction system
In my impression, compared with other brands of cars, German brand cars have more profound attainments in human-computer interaction system. However, now more and more manufacturers are starting to build their own human-computer interaction systems. Unlike the former, they prefer to realize some ideas with a basic and mature system architecture. The CUE system of Cadillac XTS belongs to this category, and the resulting experience is really different from others.
◆ Focus on user experience
CUE system began to be developed in 2008. In order to create a revolutionary experience, in the research and development stage, the system designer conducted a follow-up survey of 32 drivers for half a year and recorded their driving habits one by one. Then, engineers and designers conducted research and development based on these summarized data and corresponding technologies, and finally integrated the CUE system with the vehicle through modeling, visual feeling of the screen and touch feeling.
The traditional physical buttons can’t be found in the center console of Cadillac XTS, and the control panel is changed to the same capacitive touch technology as the display of the center console. Although this is rare in cars, most people can adapt to this operation mode quickly. After all, it is not much different from the electronic products you play with all day except the size. In order to counteract the fuzzy feeling of the touch panel during operation, the system gives a certain feedback effect by vibration, but to be honest, I don’t like this slightly abrupt vibration feeling very much. Unfortunately, the system does not support the function of adjusting or closing the vibration intensity.
◆ Development of operating system based on Linux
CUE system is developed based on Linux operating system, and the familiar Android system occupies most mobile terminal devices except Apple. From the daily experience, the platform of Android system is more flexible, which means that there are more choices in the use of application software. For Cadillac’s CUE system, it can connect with the mobile phone via Bluetooth, and use 3G network to download the application software needed by individuals. In order to ensure the security of the system, all software from third parties need to be certified by Cadillac before it appears in the download interface.
At present, the development authority of the application software around the CUE system has not been fully opened to the outside world, so its advantages cannot be released for the time being. However, the 8-inch multi-touch LCD screen is ready for this purpose, and the page-turning ability of supporting up to 5 screens is comparable to that of mobile phones in terms of code placement of application software. But from another perspective, how many third-party software development organizations will CUE attract? This has a great relationship with the coverage area of CUE system.
◆ Two-picture information flying interaction
The design of screen and software is the key to improve the experience, and the hardware is the foundation to realize all this. CUE system adopts ARM11 series of three-core processors, which are widely used in smart phones. This makes the CUE system more comfortable in running application software, navigation and picture processing of display screen. However, in the process of operation, finger movements and screen changes are not as smooth as smart phones such as iPhone.
The all-digital instrument and the center console display screen, which can realize the flying interaction of double-screen information, are one of the highlights of the CUE system. By using the touch technology and the data interaction between the two displays, the driver can move the information in the center console display screen to the all-digital instrument for display, and this process only needs the finger to move. This unprecedented experience can really make people shine.
◆ All digital instruments support four background modes.
◆ Entertainment function
☆ Seamless connection with the mobile terminal is realized.
Let’s take the mobile phone as an example. After connecting with the mobile phone through Bluetooth, the CUE system will integrate the information in the mobile phone. In addition to the phone book information, music files will also be classified. Moreover, the list of online music such as QQ music will also appear in the entertainment files of the CUE system, which embodies the concept of "cloud".
☆ Rear row equipment
The entertainment function of the CUE system itself is also very powerful. The central control display screen and the rear display screen can play different video contents through the Blu-ray drive or other external media devices installed in the glove box. In my opinion, this is very good, but if a split-screen display is needed in an actual car, more demand may be two passengers sitting in the back row, just like video equipment on an airplane. Since each seat is equipped with a display screen, the passengers in the back row will feel somewhat disappointed when they find that they need to accommodate each other during the video playback. Of course, two people watching the same content will also produce more common topics.
For more information about the experience of CUE system, please click the following link:
● Other details
◆ Active noise reduction and mute system
In order to improve the quiet degree in the car, Cadillac XTS is equipped with an active noise reduction and mute system (ANC) provided by Bose. When the system detects the presence of noise, the BOSE sound system assembled in the car emits sound waves in opposite phase to the noise, so as to cancel the noise in the car. This set of active noise reduction technology from audio is also used in headphones.
◆ Multi-directional channel adjustment
◆ Glove box with password lock
Cadillac XTS also installed a password lock for the glove box by using CUE system. When lending a vehicle to others or sending it for repair, you can protect your privacy through an encrypted glove box. The encryption is set to be one-off, and the previously set password will be invalid after the owner successfully unlocks it, which is similar to the safe in the hotel.
◆ Head-up display
◆ Parking aid system
◆ on star
Editor’s summary:
Americans seem to have more say in the creation of user experience, which is more felt by European mobile phone manufacturers who once thought they would last forever. Which field will be subverted next? Vehicle man-machine interaction system? The emergence of the CUE system is expected to break the tripartite confrontation of German cars in the field of human-computer interaction system. However, it is not yet time, because from the actual experience, although it has certain expansion ability, the operation fluency of the CUE system has not reached my expected effect (the previous publicity mostly compared with Apple products, which invisibly raised people’s expectations for the CUE system). If it can be further optimized in hardware and software, it may really be deeply rooted in people’s hearts over time. It can only be said that the CUE system adds a lot of color to Cadillac XTS.
At the beginning of the article, it is said that GM has found a strong rival for Cadillac XTS in China market-Audi A6L. At present, the BMW 5 Series is the most threatening car to Audi A6L. Although Cadillac is both high-end in brand value and XTS is also striving to build its sense of science and technology, the products of these two brands are completely different in China market. What will impress the consumers who need medium and large luxury cars? This question really needs deep thought. (Photo/Text car home Li Boxu)
Related links:
● Automobile technology is difficult to understand? Car design is too far away? Who said that? These contents can also be very interesting!
> > Want to know more about cars and become a talent? Let’s go to car home Science and Technology! <<