Intervene 15 times and bypass the jam! Is Zhijie R7 better than Xiaomi Yuqi in assisted driving？

[Interpretation of car home’s New Technology] Speaking of Bosch, you are no strangers. This well-known enterprise from Germany has too many auras and countless fist products. But if I tell you, these guys have recently developed many strange technologies, such as intelligent drift, old drivers braking … You must doubt whether Bosch engineers are working seriously? Don’t worry about the evaluation, let’s follow our footsteps and come to the Bosch (Hulunbeier) Automobile Test Technology Center with a cold wind to find out.

zeroThe motor started too hard? DTCS: arranging

In order to better control the vehicle, Bosch developed ESP? in the era of internal combustion engine. Body electronic stability control system and TCS traction control system. To put it simply, the former can reduce the offset trajectory of the vehicle during sudden braking and improve the braking safety by quickly braking continuously and adjusting the braking force of four wheels; The latter is to control the output power of the engine to ensure that the vehicle will not be out of control because of excessive acceleration torque.

The unique torque output characteristics of the motor really shorten the speed-up time of 0-100km/h, which brings an acceleration experience that many high-performance engines can’t match. But it is precisely because of this feature that it is easy for tires to break through the adhesion with the ground, resulting in vehicle instability. To put it bluntly, it is-slipping at the beginning.

Due to the output characteristics of the engine, the increase of torque needs to wait for the increase of rotational speed, so the delay of 100ms is completely sufficient. Even if many high-performance vehicles step on the accelerator deeply in the initial stage, it is not easy to cause slippage with the help of TCS.

However, the torque output of the motor is explosive, and the speed can be increased to more than 10,000 rpm in an instant, which makes the traditional TCS seem a bit "late". Therefore, Bosch engineers try their best to shorten the trigger delay of TCS according to the characteristics of the motor. Thus, the distributed traction control system dTCS was born.

According to the official disclosure, it takes only 10ms from the wheel speed sensor sensing that the vehicle is slipping to the completion of the torque limiting operation. It’s like the "high-Ping warrior" in the team just now turned on a game accelerator, and naturally he can get a better game experience.

Not only that, this set of dTCS also supports OTA upgrade. As long as the model is equipped with Bosch’s IPB intelligent integrated braking system, in theory, new functions can be written through OTA. However, at present, the official has only opened this function to Han EV. As for when other models equipped with IPB can enjoy it, it still needs specific planning.

zeroKinetic energy recovery is also slipping? EDTC: I will do it.

Many electric vehicles will automatically activate the energy recovery function when the vehicle releases the accelerator pedal to convert the wasted kinetic energy into electric energy and store it again. Frankly speaking, it is the "single pedal mode" promoted by many car companies.

EDTC has the same effect as dTCS mentioned above, and it also integrates this software algorithm into MCU motor controller. However, it controls not the "acceleration torque" output by the motor, but the "deceleration torque" generated by kinetic energy recovery. By shortening the communication path, the delay of issuing instructions is reduced.

In fact, dTCS and eDTC have one thing in common, which is to transfer the algorithm originally designed in the braking system to the motor controller. We should know that electronic control is one of the three cores of new energy vehicles. Nowadays, the design of electronic control system of vehicles is often in the hands of car companies themselves. If you want to write a black box algorithm here, it must be a very close cooperative relationship. However, according to Bosch’s engineers, they have already landed projects, and it is estimated that before long, things that can save lives at these critical moments will be quietly arranged in our car.

zeroBaby mode: Say goodbye to the brakes.

Maslow first put forward the hierarchy of needs theory in a paper "A Theory of Human Motivation" in 1943. Generally speaking, after meeting the security needs, human beings will begin to pursue higher-level needs. Such as socialization, respect and even self-realization. The same is true in the automobile field. After cars become more and more safe, the demand for comfort and entertainment begins to surface gradually.

Many consumers are prone to feel uncomfortable when riding a car, and one of the most important reasons is to brake and nod. At the moment when the vehicle is about to stop completely after deceleration, if the driver is not an old driver and doesn’t know to take a little throttle, then the last "trembling" will make the unsuspecting occupant lean forward and then be thrown back to his seat.

CST 2.0 relies on Bosch’s decoupled intelligent braking system, and both DPB and IPB can realize this function. Simply put, the model-based algorithm releases a certain braking pressure for the driver at the moment when the vehicle is about to stop. Even if the driver doesn’t loosen the oil, the vehicle can realize the effect of loosening the oil independently.

Then some friends may ask, won’t the braking distance be extended if the vehicle releases the braking pressure on its own initiative? What if it leads to a rear-end collision? We can think of problems, and engineers can certainly think of them. Therefore, this technology has considered several situations at the beginning of design.

● In case of emergency braking, whether the driver operates or the AEB system is triggered, CST 2.0 will not be activated when the deceleration of the vehicle reaches a certain threshold. The vehicle can be under the ideal braking force until the vehicle stops. After all, it’s almost hit, so don’t pay attention to comfort and discomfort. Safety comes first.

● If the vehicle triggers the ABS function for various reasons, CST 2.0 will not be activated. This tire is almost hard to grasp, so let’s forget about nodding. It’s reasonable.

● If the vehicle is driving on a ramp and the gradient exceeds the preset value, CST 2.0 will not be triggered for safety reasons. If you really want to learn from the old driver, you will be in trouble.

Technology alone is not enough. If you want to sell something, you have to rely on packaging. Bosch engineers have even named the function: according to different softness, this function can be switched between "baby mode", "commuting mode" and "customized mode" at will. According to my actual experience, I think the baby mode experience is the most comfortable, and I can hardly feel any brake nod. You just pedal and leave the rest to CST 2.0.

zeroIntelligent drift? Just get in the car?

What is the most important thing to do when you come to the ice and snow field? Of course, driving a car is a hearty drift show. However, it is very difficult for most drivers to control the vehicle stably in this state that is about to get out of control. The accelerator pedal is too small to break through the grip limit, and the floating fails; When the accelerator is stepped on, the vehicle oversteers and turns in circles. So, if there is such a technology that can help drivers control the power output of vehicles, will drift become very simple? Bosch calls this technology iDCS, which is the intelligent drift system of new energy vehicles.

The traditional car drift skills are actually very complicated. It requires the driver to break the grip balance of the rear wheel through the cooperation of the throttle and the steering wheel, resulting in "tail flick", and then adjust the angle of entering the corner in the reverse direction. It is also necessary to constantly correct the throttle opening and steering wheel angle to keep the vehicle in a state of insufficient grip. Even experienced drivers need to choose familiar vehicles and practice for a long time to ensure stable and controllable drift and perfect posture.

Even a driver like me, who is not good at drifting, can simply drift with the help of iDCS. As the trajectory of the vehicle is gradually straightened, the accelerator pedal is pressed again in the reverse direction while releasing the throttle, and the vehicle will adjust its attitude and drift in the reverse direction under the control of iDCS to complete a classic "pendulum" action.

"The cooperation of front and rear axle dual motors is not the difficulty of iDCS, even if there is only a rear axle single motor, this technology can be applied. Its complexity lies in the matching of different models. Because the chassis and suspension characteristics of different models are different, targeted adjustment and calibration can make it complete the drift action instead of Spin. "

This system does not need additional hardware support, in other words, "just have a wheel." It can not only be a good helper for drift introductory teaching, but also become a unique selling point of high-end new energy vehicles. It is understood that Bosch has even started a specific cooperation project with a new energy brand in China, but when we asked which OEM it was, the engineer said that it could not be disclosed for the time being.

zeroWrite it at the end

In fact, a day’s ice and snow experience is far more than the above contents, such as VDC 2.0 vehicle dynamic control system, off-axis torque distribution eDTD, and steer-by-wire system SBW, which are not easy to display in graphic form. We will share them with you in the form of video in the future.

I have to say, once the supplier starts to play dirty, there will be nothing wrong with the OEM. Now they not only have to develop various technologies about safety for their customers, but also have to constantly innovate and toss some interesting "tricks". Even the product name has been given, and it is really "rolled up". I hope that all major car companies will work harder and don’t let Bosch steal the limelight. I also hope that these practical and interesting functions can be introduced to the market as soon as possible, so that we can have a good experience on the commercially available models. (Photo/Text car home Yang Peng)