This article is reproduced from GeekCar, author of the White Secretary
A few years ago, Toyota could not have thought that its Lexus RX450h was bought and transformed by an Internet company such as Google, eventually becoming a self-driving car, and becoming a map in numerous articles discussing such technologies.
A few days ago, someone in the United States captured the Apple Autopilot Test Vehicle. Coincidentally, the vehicle they used was the old Lexus RX450h, and it was still three.
Then the question came: Why does Google and Apple invariably choose the RX450h? When technology companies test their own autopilot technology, what are the key factors for choosing a test vehicle?
One of the most easily conceived reasons: Seeing that the RX450h is an SUV, many people will feel that the SUV has a large space and there is enough space for the computer system that houses the unmanned system.
The earliest use of Google’s driverless project was the Toyota Prius, when the trunk was like this:
However, with the development of time, Google’s unmanned vehicles have undergone such changes (Note: The figure above is Google's 2010 Prius, the following figure is the 2012 RX450h):
Some time ago, I took the Delphi-modified Audi SQ5 self-driving car and could barely see a modified car. The trunk was very flat and the computer was hidden in the spare tire.
Actually, the “originality†of the unmanned systems of different companies is not the same, such as in the trunk of the Ford Fusion unmanned vehicle:
In addition, it needs to be pointed out that the sensors of the unmanned system and the upgraded transmission mechanism also need some space. Therefore, a vehicle used for testing still has certain requirements for "space" and "size".
Space is a very important factor, but it cannot explain all problems.
Those who are familiar with the Lexus cars will find that the RX450h is a hybrid car. Is Google and Apple trying to save fuel? The answer is of course no. Since Google and Apple are doing more advanced driverless driving, using a large number of sensors and high-performance computers, the power consumption is very large.
Sam Abuelsamid, an analyst with Navigant, said, “The maximum output power of a 12V system for a fuel vehicle is 2.5kW, which is the case for most cars now. For unmanned systems with Level 4 and above, at least a 48V system is required to function properly.â€
Seeing what the analyst said, I specifically checked the Velodyne HDL-64E S3 lidar's power and found only 60 watts. It can be seen that in a set of unmanned systems, the sensor is not a large consumer of electricity, the computer system is.
Therefore, "electricity" is also very important for driverless test vehicles. Hybrid cars and electric vehicles can provide higher voltage levels than fuel vehicles. If a fuel vehicle is to be retrofitted, an additional generator is required to power the unmanned system, increasing the difficulty of conversion.
In addition to the RX450h, many of the company's test vehicles have chosen hybrid models, such as Ford, Uber using the Ford Fusion (the domestic hybrid version of Mondeo), and Nvidia using the mixed version of the Lincoln MKZ. (In fact, the two vehicles are built on the same platform, and the electronic and mechanical systems are highly similar)
There is one thing that can prove that "electricity" and "space" are very important: Toyota Research Institute released the first Level 4 self-driving car two months ago. The model is the Lexus LS600hL (a flagship hybrid model).
Of course, there are also some "alternative" companies that choose to use the car as a driverless test vehicle. For example, Nissan uses the Leaf.
As an electric vehicle, it is not a problem to supply the unmanned system with high-voltage power, but the boot of the hatchback is a bit small. As you can see from the picture below, the converted Leaf's trunk is full of stuff.
Similar examples to Nissan include Chery eQ, which was modified by domestic Baidu and Chery, and Renault Zoe, which was modified by nuTonomy, Singapore.
On the technical level, the “familiarity†with the car is another factor because if it is not refitted with the car company, it needs to “hack†some control systems.
For example, in the past, many people were keen to convert a Prius into a plug-in version of the Prius. Perhaps due to the characteristics of "Easy-to-Modify", Google first chose the Prius as a test car. Nowadays, those "self-tuning" autopilot companies that have not yet reached an agreement with car companies must take this into consideration when choosing a car test vehicle.
When talking about so many "choose cars", it must be pointed out that the auto makers will use their own cars for autopilot tests. For example, Toyota used the Lexus LS600hL and General Motors chose the Chevrolet Bolt and Volvo. XC90 and so on.
In the coming years, we will still see a wide variety of test vehicles running through the streets. However, when the technology is finally mature, these vehicles will also complete their own mission, the final form of driverless cars, such as Google's car is an example:
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