During the NIO "866" model period, NIO's chassis was ridiculed by car owners as "Schrödinger's suspension".
This is because the system update of NIO OS will affect the experience of using the suspension, and the performance and style of the suspension are different from the update of different iterations.
This phenomenon has been complained about by old users of Weilai.
At the time of the ET7 delivery, some old users were worried that there would still be a "Schrödinger's suspension".
But this time, ET7 didn't disappoint users.
"The ET7 still has a magic carpet feel in comfort mode, smooth and comfortable, but not loose, and the S-class Maybach at home feels completely different, not to mention the ES8's overly bouncy suspension."
"The chassis of the ET7 is much stronger than the 866, and with the characteristics of the tram, it is on the same level as the 56E at the chassis level."
This is the real feedback of the first users of NIO ET7.
Behind the praise is the independently developed suspension control system.
According to Xiao Baihong, senior director of VEHICLE engineering at NIO, the intelligent chassis equipped with ET7 is mainly composed of two parts:
- First, the intelligent chassis domain controller ICC (Intelligent Chassis Controller), which is also the key to Weilai's intelligent chassis;
- The second is the chassis hardware system independently integrated and developed.
NIO ICC will be fully installed on NT2.0 platform products such as NIO ET7, ET5, ES7, etc. ET7 has begun to be delivered in March this year, and ET5 and ES7 will also be delivered within this year.
With the continuous improvement of the level of automotive intelligence, the role of intelligent chassis domain controllers in all aspects of vehicle development has become particularly critical, carrying the heavy responsibility of software and hardware unbinding and software and hardware definition.
With the development trend and evolution of centralized electrical and electronic architecture, chassis domain controllers have also become a must for intelligent chassis development.
01, break the international monopoly, full-stack self-research to make the vehicle development more efficient
Full-stack self-research has always been the core weapon of the new car-making forces.
From automatic driving, to smart cockpits, to chips, batteries and other components, the new car-making forces insist on taking the "soul" into their own hands.
For car companies, the advantage of full-stack self-research is that it can obtain absolute autonomy, which will bring about a comprehensive improvement in technology and product development efficiency.
The same is true of the self-developed vehicle chassis domain controller.
In the past, International Tier 1 controlled the core of chassis control technology, providing "black box" chassis solutions for car companies.
Under Tier 1, Tier2 and Tier3 (tier 2 and tier suppliers) provide chassis-related shock absorbers, air suspensions, EPBs and other parts for their car companies, as well as more than 100 major controllers related to them.
This makes car companies need to match the development cycle of partners in the process of chassis control development. At the same time, chassis domain controller development barriers are high, the cycle is long, and it is difficult to quickly meet the needs of FOTA.
After the full stack self-research, what problems has Wei solved?
Taking the adjustment of air suspension and dynamic suspension damping control parameters as an example, the traditional ASDM needs to make an appointment for debugging resources for half a year in advance, plus the supplier release integration and OEM verification release for 1 month, which takes at least 8 months in total.
According to Xiao Baihong, after weilai independently developed ICC, it was similar to the air suspension data correction problem, and it only took 1 and a half months to quickly upgrade FOTA.
For the development of complex chassis functions, it requires joint commissioning by different departments such as first- and second-tier suppliers, and the entire development cycle takes at least 4-6 months.
After wei's self-research, it can do more reasonable system design according to its own needs, and take into account joint debugging and verification while developing algorithms, so that the research and development cycle is shortened by half.
In the development of traditional vehicle chassis, the relatively independent control between individual components and subsystems is independent, which is the main pain point and main limiting factor of traditional chassis development.
Many car companies, especially domestic independent brands, lack the ability to integrate and develop the deep functions of the chassis, resulting in vehicles that can only meet some simple basic driving experiences, with fewer extended functions and a relatively single driving experience.
With the software on the car, the chassis is no longer pure mechanical integration, the vertical integration ability of the software will make all the components integrated, improve the dynamic performance boundary of the whole vehicle.
On this basis, compared with the traditional chassis control of various components, relatively independent of longitudinal and vertical vehicle dynamic control, NIO full-stack self-developed ICC, through software and hardware intelligent collaboration, improve the dynamic performance experience of the whole vehicle, and give full play to the efficiency of the entire system, can meet richer personalized needs.
The speed of research and development brought by ICC is also reflected in the earlier stages before entering the real car tuning.
According to reports, NIO launched the first driving experience simulation platform applied to the research and development of mass-produced vehicles:
- It is composed of auxiliary facilities such as driving simulators, simulation systems, and vision systems, and can carry out virtual commissioning of vehicles, performance evaluation, and verification of various on-board systems.
- The integration of ICC modules enables it to expand more functional testing in NAD scenarios and rich operating conditions, shortening the cycle of design iterations while achieving a balance between vehicle agile development and R&D investment.
Based on the self-development of ICC full stack, NIO has broken the monopoly of foreign suspension control system "black box" solutions.
The full-stack self-developed ICC allows engineers to adjust the chassis at any time and upgrade more flexibly.
In the future, the electronic chassis will become user-oriented personalization, and after opening up the chassis control domain, ET7 can provide users with more interactivity and greater possibilities.
02. Integrated chassis domain controller, what is the difference between WEILAI ET7?
With the evolution of the vehicle's electrical and electronic architecture, domain controllers have gradually become mainstream.
Compared with the traditional ECU unit mode, the domain control mode has the following main advantages:
- Multiple functions can be integrated, including a safety system with high computing power and fully redundant functions, vehicle motion control, etc.;
- Domain controllers replace the decision-making functions of the original more independent ECUs;
- Domain controllers have powerful hardware computing power and rich software interface support;
- The core functions of intelligent control are concentrated, the real-time is high, the coordination processing speed is fast, and the system function integration is high;
- Standardized sensing and actuator parts can be developed, with strong component compatibility and a wide range of applications
In THE SUSPENSION CONTROL SYSTEM DEVELOPED BY WEILAI FULL STACK, chassis control has also been officially upgraded to the concept of "domain".
The chassis domain of traditional Tier 1 manufacturers generally integrates functions such as drivetrain, driving system, steering system, and braking system.
In addition to integrating traditional control functions such as redundant parking, air suspension, and shock absorbers, the ULCO chassis domain controller can also support functions such as high-level automatic driving scenarios and FOTA upgrades after cross-domain integration.
Equipped with ICC's NIO ET7, the systems and components on the chassis architecture have been further improved and optimized, and through the intelligent collaboration of the overall system, fusion control and rapid iteration can be realized.
Weilai said that ET7 has achieved fully autonomous positive development for the first time in China from the definition of vehicle experience goals to embedded systems, components, software hardware, and chassis domain controllers.
Specifically, based on ICC, NIO ET7 has two major advantages in product function experience:
First, ICC can fully design and adjust chassis comfort and handling.
For example, in the Dynamic Suspension Damping Control CDC, each damper hardware can change the damping by a change in current.
In the interaction between real-time on-board signals and sensor signals, the car collects a large amount of real-time on-board traffic information, and cdc software calculates the current state of the vehicle.
According to the actual situation, the commissioning engineer will seek the optimal damping setting between 1.8 amps (minimum damping) and 0 amps (maximum damping), through the layers of decoupling of software parameters.
Arranging and combining different structures by adjusting the softness and hardness is no less than playing a Rubik's Cube of hundreds x hundreds of orders, and the adjuster needs to find one optimal solution after another in this Rubik's Cube.
The use of ICC can make the ET7 suspension system have a high degree of initiative, the controller detects the state of the vehicle through the signal received by the sensor, and determines the optimal parameter instructions according to the algorithm or control strategy to adjust the spring stiffness and the damping state of the shock absorber.
With the blessing of ICC, after adjusting a large number of key components such as tires, air suspension, steering system, etc., NIO ET7 has four driving modes: Sport +, Sport, Comfort, and Energy Saving.
The suspension in Comfort Mode gives the vehicle more "breathing"; Sport mode adds correction to pitch and roll and enhances control over the body.
This allows users to have a better driving experience.
According to the data provided by Weilai, the ET7 is compared with a medium and large luxury car:
In Comfort mode, the ET7 with smart chassis and the aftershock control in the front and rear wheels in the direction/vertical direction are 40%-60% faster than the benchmark model.
At 100km/h, the COMPARISON OF THE ET7'SWA WITH LATERAL ACCELERATION LACC AND YAW RATE IS BETTER THAN THE BENCHMARK MODEL, WHICH MEANS THE ET7'S STEERING IS MORE PRECISE IN THIS COMPARISON.
Second, ICC can drive for autonomous driving scenarios and achieve multi-degree-of-freedom fusion control.
In general, in order to meet the richer functional experience in the NAD autonomous driving scenario, the chassis needs to provide a bearing platform for the automatic driving system, cockpit system, and power system.
This is also a more critical goal of Wei's main research and development of intelligent chassis - Design for AD (design for autonomous driving).
In the SCENARIO OF NIO NAD autonomous driving, the intelligent domain fusion control system can control the four-wheel drive distribution, line control movement, variable suspension and other functions of the vehicle, so that the vehicle can more intelligently realize the driver's expectations, maximize the dynamic performance of the vehicle, and continuously expand the future functional boundaries.
At the same time, cross-domain actuators can be backed up against each other, which can systematically reduce the probability of failure of key functions, thereby improving driving safety.
Xiao Baihong said that originally in the 866 era, the diagnostic protection threshold of Nio's NP/NOP system was relatively low, and if the brake/steering was reported incorrectly, the assisted driver would immediately exit. On the NT2.0 platform, including the next generation of models, WEILAI will gradually extend the exit time of high-level assisted driving caused by error reporting through mutual calibration between controllers.
At the same time, ICC will make the vehicle have a high degree of personalization in the future, relying on the continuous collection and identification of the user's personalized driving data, through human-vehicle interaction and self-learning iteration, to provide a driving experience that meets the user's psychological expectations.
In terms of traditional chassis design, tuning, etc., ICC can provide et7 with better performance.
More importantly, ET7 for the first time in the car to achieve "functional atomization", based on the software to give the car chassis a new meaning, the chassis electronic and intelligent will also bring more interactivity and greater possibilities to users.
03, behind the self-research of Weilai full stack: define the bottom layer, experience through, and increase the upper limit
At present, the traditional automotive industry chain has changed.
The improvement of vehicle intelligence, the development of software and hardware collaborative integration, and the iterative upgrading of electronic and electrical architectures make car companies no longer need to integrate various parts into the vehicle as before.
Chen Hong, chairman of SAIC Motor, has said that car companies should take the "soul" into their own hands.
But what is a "soul"?
In the era of intelligent electric vehicles, the core three-electric technology is the "soul", and the automatic driving technology capability is the "soul".
However, from the perspective of Wei, the self-development ability of cross-domain integration control is the core ability that car companies need to have in the era of intelligent cars.
The full-stack self-research ability of car companies is mainly reflected in the high degree of integration of software and hardware, and car companies without self-developed integration capabilities can only be regarded as electric vehicle enterprises, and cannot be called intelligent electric vehicle enterprises.
From the perspective of supply chain, the past series has become a model centered on car companies, with suppliers at all levels closely surrounding the surrounding model, car companies carry out software self-research, and according to design definitions and functional requirements, to find suitable partners.
With the full-stack self-research capability of cross-domain integration, NIO can provide users with a more personalized driving experience based on the user experience and based on the daily parking scene with high perception of users.
As Xiao Baihong said, if the supplier's standard solution is adopted, what materials and what dishes are used will not only limit the final product's embodiment of molding, but also limit the entire team's exploration of technical boundaries.
NIO adheres to the full-stack self-developed chassis domain controller, which mainly reflects the ability of software and hardware, which not only defines the functions of the car, but also gives a new meaning to the intelligent electric vehicle chassis:
Definition of the bottom layer: Based on the full stack self-research, NIO ET7 has four driving modes: comfort, energy saving, sport and sport +, and in addition to acceleration, energy recovery, suspension height, suspension stiffness, steering force, and even air conditioning can be customized.
Experience through: The original chassis parts and components are not interoperable, based on ICC and software capabilities, NIO ET7 opens up multiple scenarios from traditional control functions, to automatic driving and OTA upgrades, so as to achieve rapid iteration and flexible upgrades.
Raise the upper limit: NIO ET7 body length 5101mm, wheelbase 3060mm, but its actual performance is not inferior to a medium and large luxury car. This means that based on ICC, NIO can continuously improve the vehicle performance experience.
Based on user experience self-research, NIO ICC will be fully equipped on NIO's second-generation technology platform products, and is an accelerator for vehicle development and function iteration.
In the past, the vehicle chassis has been controlled by international manufacturers, and Weilai's full-stack self-developed intelligent chassis system has broken the monopoly of international manufacturers, which also represents the rise of China's high-end automobile brands in the traditional field of vehicle engineering.
The self-developed intelligent chassis is just the beginning, which means that WEILAI will have more adequate preparations in the future to bring users a better driving and riding experience.