RJ. When RJ scaringe was a child, he had a hobby. When he saw a car he didn't know in the parking lot, he would lie down under the car to better observe the chassis of the car. In 2009, general motors and Chrysler successively declared bankruptcy. That year, after graduating from the Department of mechanical engineering of Massachusetts Institute of technology, scarinchi founded a new automobile company, rivian, which was once called "Tesla killer" by domestic and foreign media.
It was Amazon founder jeffbezos, who was in a "space race" with musk, who really praised skalynch and rivian to the skies. The former richest man not only invested heavily in rivian, but also purchased 100000 truck orders from him. Bezos even used rivian's SUV for his commercial space company "blue origin" to serve as a special vehicle for astronauts.
If musk is the iron man, then the founder of rivian scarinchi is the "real Superman". It is not only because scarinchi and Superman are quite similar in appearance, but also because everyone hopes to see a good play of "Superman vs Iron Man".
RJ. Scarinchi (left), Superman played by Henry Carville (right)
Like musk, scarinchi showed a strong creative talent from an early age. In his childhood, he helped his neighbors repair the Porsche 356, which was nearly scrapped. In high school, scarinchi had a dream to build his own car company.
However, there are many differences between the two. For example, Tesla's first Roadster is based on the chassis transformation of lutes Elise. When scarinchi founded rivian, he extended his hand to his childhood hobby - Chassis .
Rivian introduced a technology called "skateboard chassis" on the mass production vehicle, based on which he created pure electric pickup r1t and pure electric SUV R1s. In addition, it also uses the skateboard chassis to customize the pure electric freight car EDV for Amazon.
As for the skateboard chassis technology, ouyangminggao, an academician of the Chinese Academy of Sciences, once made a prediction: "rivian listed in the US stock market is highly sought after for launching the smart skateboard chassis." He also believes that the skateboard chassis is the result of the evolution of technology over the years and represents the development trend of technology "This will bring a revolution to automobile design and manufacturing."
Many people will wonder whether the skateboard chassis is really so magical?
The reason why the "skateboard chassis" can become a tuyere, Apple The company definitely deserves credit.
In the past few months, a new American car maker named canoo has repeatedly been rumored to be acquired by apple. According to the verge, an overseas technology media, canoo's "skateboard chassis" platform has aroused Apple's interest. Because it integrates more automotive electronic equipment, it provides greater flexibility for cabin design. It also has steering by wire technology, which also increases the design flexibility.
Although the acquisition has not been settled yet, Ulrich Kranz, the former CEO of canoo, is now one of the senior executives of Apple's automobile project. At the same time, Apple has also poached a number of former canoo engineers. It's hard not to think that apple is developing its own "skateboard chassis" platform, or mastering other capabilities required by the platform.
Is the "skateboard chassis" platform that even apple has dreamed of so magical?
To make an inappropriate analogy, it is just like the 4WD car we used to play when we were young. It has a shell on it and a chassis under it. The motor, battery, tire, transmission shaft and other components are installed on the chassis. The upper shell can be replaced at will. Even without covering the shell, the car can run.
The same is true for the skateboard chassis in theory - as an integrated chassis architecture, the platform integrates the battery, electric drive system, suspension, brake and other components on the chassis, and finally realizes the decoupling of the upper and lower vehicle bodies. The advantage of this is that it is highly integrated and versatile, which can significantly shorten the vehicle development cycle and reduce the R & D cost.
Rivian's upper and lower car bodies separate
At the 2018 Los Angeles Auto Show, rivian released two electric vehicles based on skateboard chassis, which attracted the attention of Amazon, Ford and other giants. After visiting the company in person, Amazon of Bezos took the lead in investing $700million in rivian in february2019. Two months later, Ford invested another $500million in rivian.
As a technology giant and a century old auto company, rivian's valuation took off instantly. In September, 2021, rivian's first mass-produced electric pickup truck r1t was officially launched. However, large-scale delivery did not start. Then in November 2021, rivian officially landed on NASDAQ and raised US $11.934 billion, becoming the largest IPO in 2021 and the sixth largest IPO in the history of US stocks.
Amazon's investment in rivian is almost a conspiracy.
Because based on the skateboard chassis of rivian, the pure electric van EDV delivered to Amazon can be manufactured. Theoretically, it can also be used to produce smaller unmanned delivery vehicles in the future. This has brought Amazon's e-commerce and logistics business a huge imagination space.
Pure electric van EDV produced by rivian for Amazon
The same is true of Ford. The original plan was to use a skateboard chassis to develop a new electric SUV for its Lincoln brand, shortening the R & D cycle and investment. But later, only Amazon's electric trucks were mass produced, while Ford's procurement plan for the skateboard chassis platform was shelved.
Because on commercial vehicles, Amazon only needs to solve the problem from 0 to 1 to help the express brother transport goods. As for the performance and functions of the vehicle, it doesn't matter. However, unlike passenger cars, it is difficult to solve the problem from 1 to 100. For example, with the platform, how can the handling, performance, endurance and other parameters be at a more advanced level in the industry.
When we focus on rivian, a new car company whose market value once ranked the third in the world, you will find that it is highly sought after by capital, not only because of the commercial value of the skateboard chassis, but also because of the new technologies and new experiences based on the platform.
In the first two years of the venture, scarinchi followed Musk's steps to develop an electric sports car. But in 2011, scarinchi began to re-examine the company's priorities. He said: "it is becoming clear that we have not answered the questions the world needs to answer."
MIT genius scarinchi and his team had to give up the research and development of electric sports cars, really considered the needs of the world, and finally found their reason for existence: developing electric cars to promote a positive lifestyle and promote travel that can generate lifelong memories.
Scarinchi often wears Patagonia's woolen sweater and is a down-to-earth outdoor sports enthusiast. When making electric vehicles, scarinchi re recognized the trend of technology - "we hope to embed the vehicle into a technology platform to help promote sustainable development and obtain more electric miles on the road."**
Therefore, we can see that the battery capacity of rivian starts with 100kwh. For example, the lowest version of pickup r1t is 105kwh, followed by 135kwh and the highest 180kwh. Currently, 2170 batteries supplied by LG are used. Under the more stringent EPA standards, the endurance mileage is 230 miles (370 km), 300 miles (480 km) and 400 miles (640 km) respectively.
The endurance may not seem high, but remember that the total weight rating of the r1t is 8532 pounds - basically a heavy truck. Most importantly, rivian worked on the battery pack.
Zhuyulong, a senior automotive electronics engineer, has analyzed rivian's battery pack:
Rivian's design idea also starts from the 21700 battery. The main scheme is to make full use of the way that pickup trucks and commercial vehicles are highly insensitive to the Z direction, and adopt the sandwich method that the upper and lower modules are equipped with cooling plates.
This is a different path from the iterative design of the cylindrical cell. The two modules are cooled from top to bottom on one side, and a large cold plate is used between the modules. The cells here are placed upside down. The cells are first made into a single module. The actual module height is relatively high, which is equivalent to combining two 21700 modules together. On the front of the module is the output line row of the module, which is bridged through the quick plug connector. On the other side of the battery module, the upper and lower bus bars are connected through the bus bar.
Through this large module, rivian can form a large battery system.
In fact, there are many ways to stack batteries at present, such as the CTC (cell to chassis) technology used by Tesla, which directly installs the seat on the battery cell. Remove the module to realize a larger battery pack.
However, at this stage, rivian is really stacking batteries, stacking the two modules up and down. As the assembly process is relatively complex, rivian uses more labor in the module assembly process.
Rivian's "cylindrical battery cell packaging and cooling configuration" patent
However, in scarinchi's view, it's worth it - "one of the challenges of automobile production is that you apply human thinking to the right place, rather than trying to over robot the factory. Therefore, some parts of the factory have been roboticized, especially in how we build battery modules, and many other parts will continue to use manpower."
In short, the skateboard chassis is extremely friendly to the battery pack, because the overall structure of the skateboard chassis is very similar to the girder chassis of the non load-bearing body. It has an independent frame, which means that the skateboard chassis has an independent structure and strength. Therefore, in the design, although the cell is used as a structural member, it does not need to carry too much load.
Because of the existence of the skateboard chassis, it will be easier for rivian to be compatible with CTC technology or solid-state batteries if it wants to continue to stack mileage.
Scaringer's past academic experience focuses more on internal combustion engines. Under the guidance of Professor Wai Cheng, he conducted master's and doctor's research on how to expand the load limit of homogeneous compression ignition engine (a low emission internal combustion engine).
Even in the era of electric drive, scaringer still did not give up his research attitude towards the drive system.
Of course, there is a misunderstanding here. Many people think that rivian uses a hub motor. In fact, rivian adopts a drive system placed at the wheel side, which can achieve the torque required by the vehicle through the motor reducer, and at the same time can control and drive respectively, effectively solving some disadvantages of the hub motor and its impact on the vehicle.
Rivian's four motor layout
In such a compact automobile chassis, it is necessary to place four drive motors and reducers, so the integration of the powertrain will have higher requirements. However, from the picture effect, rivian has solved these problems well, and based on this set of drive system, rivian has achieved the comprehensive maximum power of 562kw, the maximum torque of 1120n · m, the fastest acceleration of 100 km for 3 seconds and other dynamic parameters.
"Each wheel has the same torque and power values for optimum performance." Richard Farquhar, vice president of rivian in charge of powertrain, introduced that rivian, with a single speed gearbox with fixed gear ratio, does not need to shift gears and does not need to use a two speed gearbox, which can minimize the efficiency consumption caused by gear meshing and achieve the performance objectives to the greatest extent.
In addition, rivian's power assembly also integrates its self-developed inverter. "The inverter is an important part of the propulsion system, which is equivalent to the Pearl on the crown. The equipment is completely independently designed by us." Richard further said, "we have designed a dual power inverter, which is integrated into the electric drive assembly and can control two motors on an inverter assembly very efficiently."
In his opinion, from battery to inverter, to motor and even wheel, rivian has invested a lot of energy in the whole three electricity system, so as to maximize the electrical efficiency, so as to use the established energy to maximize the vehicle mileage and dynamic performance.
The ultimate vehicle performance brings the ultimate driving experience, especially as an off-road pickup /suv
Rivian has four wheels, which can provide instant power and adjust the torque of each wheel independently, because precise traction control can be achieved under all conditions. Controlling the power of a single wheel can realize torque vector control, which can eliminate oversteer and understeer, so as to maintain the stability and response of the vehicle through rapid maneuvering in off-road and snow.
In the wild, rivian can also achieve a more cool off-road function - tank U-turn.
In this mode, rivian independently controls the wheel rotation through four motors, which can realize the reverse rotation of the wheels on both sides, thus achieving the same effect as the reverse rotation of the tracks on both sides of the tank, and realizing the real in-situ rotation.
Ford has previously applied for a tank turning technology patent for its F-150 ev. Although the effect may be similar, the F-150 EV has only a dual motor version for the time being. It can not control each wheel independently like the rivian r1t with four motors, and the playability is much less.
Rivian's "tank U-turn" patent
Rivian adopts the drive form of "wheel motor". Although it can not meet the extreme requirements of the wheel motor (integrating the motor on the tire) on the spatial layout, it at least meets the all-round requirements of the model for performance and functions.
Especially in terms of heat dissipation, the wheel motor can be better integrated with the power battery system for thermal management. For example, heating the battery pack can rely on the heat generated by the drive system and inverter rather than independent heaters with higher energy consumption and cost.
To this end, rivian has developed a battery with special heating and cooling circuits, which can intelligently prepare the best temperature for the battery as required. In very cold environments, the battery is kept at a high temperature to maximize its efficiency. The same principle is also applicable to separate traction circuit to keep the motor and inverter in the best state. The motor and inverter have a water glycol circuit for cooling the stator and power electronic equipment, and a third circuit for the passenger compartment and inverter.
In short, by taking advantage of the skateboard chassis in the spatial layout of chassis parts, rivian has indeed brought some freshness to the driving level of electric vehicles. This is also the flag established by Richard Farquhar, vice president of rivian -- "in terms of engineering mechanics, our power system and chassis system have reached such a level that no one can do better than us."**
After some innovation on the chassis system, the skateboard chassis technology will start a new round of subversion on the car cabin.
You know, most cars now have a very important mechanism called steering column. When the driver turns, he can drive the wheel to turn through the steering column only by breaking the steering wheel. However, due to the existence of such physical mechanisms, the space in the cabin is often constrained. In order to break through this framework, GM first introduced the concept of chassis by wire on the hy wire concept car.
In a sense, the skateboard chassis is an extension of the "full line control chassis". For example, steering by wire is equivalent to completely canceling the mechanical connection and only realizing steering through electronic control. When you turn the steering wheel, you input an electrical signal, which is then transmitted to the steering actuator to complete the wheel steering. Only when it is separated from the mechanical control, the control can achieve the ultimate modularity and compactness of the mechanism.
Rivian's sliding plate chassis has a steer by wire / brake system, which allows the steering ratio of the steering wheel to change at any time and realizes the road feel feedback of different steering wheels. In addition, with the cooperation of its independent air suspension, hydraulic roll control and other systems, rivian has finally realized eight driving modes on pickup trucks, which are customized according to personal driving preferences or different road conditions.
In addition to higher playability in driving mode, the chassis by wire can better cooperate with automatic driving.
Rivian published a patent last year for "systems and methods for operating autonomous vehicles in guardian mode". This technology can define the driving mode of autonomous vehicles, and prohibit or enable multiple capabilities of vehicle control. It can be said that these systems are based on the outstanding accumulation of rivian's online control technology to increase the innovation of human-computer interaction mode with the members in the vehicle.
Because the traditional vehicle using EPS (electric power steering) is limited by many factors, such as installation space, force transmission characteristics, angle transmission characteristics, etc., it cannot be designed freely. As a result, the steer by wire system, which can be "completely separated" from the driver to achieve steering control, is very suitable for the needs of automatic driving. This feature makes steer by wire and automatic driving a pair of "good brothers".
Of course, after rivian has done a lot of subtraction work on the chassis, the most direct benefit for users is to increase the driving space and storage space in the car. For example, rivian has more than 62 cubic feet of storage space between the front luggage compartment, rear storage compartment, under seat compartment, center console and gear channel.
Rivian spacious front row
The front luggage compartment alone has surpassed almost all electric vehicles at present. Rivian gave the data: 25.4 x 54.8 inches, with a depth of 22.7 inches There is no problem for an adult to lie in
Rivian's oversized front trunk
With the release of the entire chassis space, rivian can leave a left-right connection gap at the rear wheel of the pickup r1t, which can not only be used to store long items such as skis and fishing rods, but also become a folding kitchen.
The device called "the gear tunnel shuttle" is pulled out like a small folding table, but the modules on it can be spliced for various purposes. For example, you can spend $5000 (about 32000 yuan) to choose a customized version of snow peak camping kitchen module.
Scarinchi is showing this kitchen module
However, scarinchi, a founder with a background in science and engineering, does not have a deep obsession with the subversion of the cockpit, but only meets the basic needs of accommodating more camping outdoor equipment.
But in contrast, canoo, which was targeted by apple, played out the smart cockpit on the skateboard chassis.
The first product launched by canoo is called lifestyle vehicle. It not only has a unique shape, but also benefits from the space advantage of the skateboard chassis in terms of interior decoration. It can make it almost flat on the ground. At the same time, the placement of seats can also be whimsical. Canoo put down a circular sofa in the back, which can accommodate 7 people.
Shortly afterwards, canoo released a second car, a multi-purpose delivery car similar to the EDV customized by rivian for Amazon. Canoo named it mpdv. It can not only land in the express logistics scene, but also act as a mobile coffee shop, fruit stall and so on; Later, canoo announced its third car, pickup truck; The fourth car to be released soon is a sports car, whose appearance and interior still maintain the unique sci-fi color of canoo.
In the final analysis, the emergence of skateboard chassis technology has unleashed the imagination of designers and unleashed the creativity of engineers. In this stage of gradual convergence of product forms of electric vehicles, it is not a new way to solve problems**
These "skateboard chassis concept" companies are not doing well when we put time back to the present.
Rivian, a new force that once set the record of the largest IPO in 2021 and the sixth largest IPO in the history of the United States, saw its share price plummet by more than 70% this year. As of May 31, rivian's market value was only US $28.281 billion, down more than 80% from the peak of US $161.6 billion. What is more fatal is that Ford, as its fourth largest shareholder, recently began to sell a large number of rivian shares.
You know, Ford originally planned to use rivan's skateboard chassis on its Lincoln brand pure trams, but this matter was never settled. In addition, Ford also built a pure electric version of F-150 lightning based on the F150 fuel vehicle chassis through the "oil to electricity" method. Overnight, the relationship between father and son turned into an adversary relationship. This change also seems to mean that Ford began to give up its obsession with the skateboard chassis.
Similarly, canoo, which landed in the capital market with the help of the skateboard chassis concept, is basically lying flat and waiting for apple to buy it. As of March 31 this year, canoo had only US $104.9 million in cash and cash equivalents. In the first quarter, canoo had no revenue, and its net loss reached US $125.4 million. According to this loss rate, the company will not live until the next quarter.
"Huawei's core values" once mentioned: "almost 100% of the company is not dead because of its poor technology, but because the technology is so advanced that others have not fully understood and recognized it, so that no one will buy it. The products can not be sold, but they consume a lot of human, material and financial resources, and lose competitiveness. Huawei should keep its technology leading, but it can only be half a step ahead of its competitors. If it is three steps ahead, it will become a martyr."
Today, rivian and canoo are both wandering between the two extreme roles of "leader" and "martyr".
Of course, we cannot deny the commercialization prospect of "skateboard chassis" based on the short-term difficulties of these two companies. This is just as stupid as issuing a "bankruptcy warning" to musk when Tesla was in a capacity purgatory in 2018.
What if the "one more thing" of the press conference, apple cars "treading on the skateboard chassis" made a grand debut?