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來源：
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The secret tech behind the Tesla Model 3

標題：Tesla Model 3 背後的秘密技術

When it comes to Tesla, attention is usually focused on its production
struggles, the latest actions of company founder Elon Musk or, from a
technology perspective, its pure-electric powertrains. But with the Model 3,
the firm is also aiming to pioneer a new approach to chassis and suspension
design.



Tesla’s approach to designing those areas, which are crucial elements in
defining a car’s character and desirability, didn’t follow usual automotive
industry practice for volume car production. Autocar spoke exclusively with a
number of Tesla engineers to gain an insight into that development process.

Tesla 設計這些部件的方法，是確定車輛個性和可取性的關鍵因素，他們並沒有
遵循汽車行業一般量產汽車的做法。 Autocar 專門和眾多Tesla 工程師進行了

Most manufacturers these days build major new models from a platform or
architecture, but when it came to the design of the Model 3’s chassis and
suspension, Tesla engineer stuck with a ‘first principles’ clean-sheet
approach. The starting point were the tyres, which Tesla describes as the
unsung heroes of its cars and crucial to feel and drivability. Development
started in 2015 and Tesla worked with tyre manufacturers for almost three
years, which is longer than the time spent on the Model S’s tyres.

如今大多數製造商都是從平台或架構中構建主要的新車型，但在設計Model 3 車
架和懸吊時，Tesla 工程師堅持使用"第一性原理"達到其需求。起點是輪胎，Tesla
稱其為車輛的無名英雄，對駕駛感覺和性能至關重要。開發於2015年開始，Tesla
與輪胎製造商合作將近三年，這比花在Model S 輪胎上的時間更長。

https://i.imgur.com/V80QZE0.jpg

Tesla says tyres for a high-performance electric vehicle are challenged in a
way that those on a car powered by an internal combustion engine (ICE) are
not. A two-wheel-drive Model 3 with a long-range battery weighs just over
1700kg, so tyres have to cope with high loads as well as a 155mph top speed
(for dual motor versions) plus continual torque input, either when
accelerating or during regenerative braking.

Tesla 表示，高性能電動車的輪胎受到的挑戰是現在的輪胎是為了裝在內燃機(ICE)


The bulk of mass of an EV is usually located lower than in an ICE-powered car
due to the battery packs being mounted under the floor. As a result, there is
less vertical force build-up through the outside pair of tyres to generate
grip when they corner. To tackle that, Tesla focused on tread stiffness,
developing new compounds to deliver the desired combination of cornering grip
and low rolling resistance. The tyres are filled with sound-absorbing foam to
suppress noise amplified inside the tyre cavity.



Each rear wheel has six degrees of freedom – five links and one damper,
similar to a double wishbone – but the links have been split to give better
control over the forces transmitted through the tyre’s contact patch. The
front suspension has also been designed to provide maximum protection in the
stringent, small-overlap frontal collision crash test.



https://i.imgur.com/GMPvnzW.jpg

Apart from the direct injury that can occur in accidents, doors can jam and
EV batteries can be threatened too. To counter this, sacrificial links are
designed to snap when the front wheel and suspension takes a hit.

除了事故中可能發生的直接傷害外，車門也會卡住，電池也可能受到威脅。為了
解決這個問題，連桿設計成在前輪和懸架受到撞擊時可被犧牲折斷。

That allows the wheel to rotate around a third link, moving the wheel outside
of the body and pushing the car, the occupants and the batteries away from
the point of impact.

這可使得車輪圍繞第三連桿旋轉，將車輪移動到車身外部並且將車輛，乘員和電

The additional motor in all-wheel-drive variants sits on two mounts in the ‘V
’ of the front subframe and pivots backwards into a void in the event of a
collision. The electric power steering system has a rapid 10:1 ratio, giving
two turns lock-to-lock. The system has full redundancy with separate power
feeds taken directly from the high-voltage battery, two electronic control
modules and two inverters providing ‘hot backup’ if one fails.

全輪驅動車型中的另一個電機位於前副車架兩個骨架的"V"中，並在發生碰撞時


https://i.imgur.com/JJ6Supx.jpg

Tesla’s engineering team opted to fit more expensive four-pot brake calipers
at the front of the Model 3 rather than a cheaper, single-piston sliding
version for superior pedal response. That also allowed the firm to design its
own piston seals that fully retract the brake pads after braking, cutting
drag and boosting the available driving range.



The discs themselves have been designed to last for the life of the car
(about 150,000 miles), which is possible because the Model 3’s regenerative
braking system reduces how much the conventional brakes are used. Rust could
be an issue over that time, so engineers developed new anti-corrosion
techniques. Such attention to detail is indicative of the development team’s
‘more and’ mantra: if an improvement is made in one area, whether for
performance or cost reasons, Tesla’s team commits to making another
improvement elsewhere.


因此工程師開發了新的防鏽技術。對細節的這種關注解釋了開發團隊的"more and"

口頭禪：如果在一個領域做出改進，無論是出於性能還是成本原因，Tesla 的團
隊保證會在其他地方做到另一項改進。



What’s the frequency, Elon?

Tesla drew on learnings from Nasa when refining the Model 3’s suspension
settings to ensure the car would be comfortable.


the limits of human capability, which included research into how long the
body can be subjected to a certain frequency without feeling uncomfortable.

這家加州公司的工程師們為了學習了解人類能力的極限而向太空機構求助，其中
包括研究人體在受到特定頻率影響下有多長時間不會感到不適。

The vertical frequency (measured in hertz) at which the suspension moves
affects not just comfort but how a car feels to drive, whether it be relaxed
and serene or sharp and edgy.

懸架移動的垂直頻率(以赫茲為單位)不僅影響舒適性，還影響駕駛感受，無論是

Tesla says the suspension of most cars is sprung and damped to move at
between 1.0Hz and 3.0Hz. For the Model 3, engineers settled on a vertical
frequency for the suspension that is equivalent of a brisk walk or a slow run
to give a chassis feel that was comfortable yet sporty enough to harmonise
with the performance of the powertrain.




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