好英语网自行车如何保持平衡？诀窍都在大脑中
It’s as easy as riding a bike… or so the saying goes. But how do we manage to stay upright on a bicycle? If anyone ventures an answer they most often say that it’s because of the “gyroscopic effect” – but this can’t be true.
英语里有一句谚语叫“像骑自行车一样容易”。但是人们究竟是如何在自行车上保持平衡的？很多试图尝试回答这个问题的人会谈到“陀螺效应”，但实际上并不准确。
Put simply, the gyroscopic effect occurs because a spinning wheel wants to stay spinning about its axis, just as a spinning top or even planet Earth stay aligned to their spin axes. While motorcyclists with their big, heavy, fast-spinning wheels may notice the gyro effect, a modest everyday cyclist won’t because the wheels are much lighter and at a leisurely riding speed they don’t spin quickly enough.
简而言之，陀螺效应的产生是由于轮子在旋转中能保持轴的方向的能力，就像一个旋转的陀螺，或者围绕轴心旋转的地球。摩托车手由于驾驶飞速旋转的重型机车会更容易意识到陀螺效应的作用，但是普通的骑车人由于使用的轮胎轻得多，速度不够快而不会注意到陀螺效应的存在。
If a pedal bicycle did stay upright because of the gyroscopic effect then any novice getting on a bike could just push off and the bike – and the effect – would do the rest. The simple truth is that you have to learn how to ride, just as you must learn how to walk. Riding a bike is all in the mind.
如果脚踏车可以因为陀螺效应而保持直立，那么任何新手都可以坐在上面不用蹬车，被人推着前进了–因为陀螺效应本身就可以发挥作用促使车辆前进。简单来说，你必须学会如何骑车，就像你必须学会如何走路一样。驾驭一辆自行车的关键全在大脑中。
Imagine you had to ride along a perfectly straight line on a perfectly flat path. Easy, surely. Well, no. It’s virtually impossible to ride along a narrow straight line just as it’s really hard to walk perfectly along a straight line, even when you’re not drunk. Try it.
想象一下，你沿着一条完全平坦的笔直的道路骑行。非常容易是不是？嗯，并不是，基本上人很难沿着一条狭窄的直线骑行，就像不可能走出一条完美的直线一样，即便是在你完全清醒的情况下，不信你可以试试。
Now attempt this little experiment: stand on the ball of one foot, using your arms to balance. It’s quite hard. But now try hopping from one foot to the other. It is much easier to keep your balance. It’s called running. What your brain has learned to do is to make a little correction every time you take off so that if, say, you’re falling to the right, then you’ll hop a bit to the left with the next step.
现在尝试这个小实验：一只脚站在球上，用你的手臂来保持平衡。非常难。现在试着从一只脚跳到另一只脚。这样保持平衡容易的多。这个过程叫做跑动。你的大脑所做的是每次你起跳的时候根据位置进行调整，这样如果你朝右边倒了，下一步大脑就会指导你往左跳一些。
It’s the same with pedalling a bike. When riding, you’re always making tiny corrections. If you are falling to the right, then you subconsciously steer a bit to the right so that your wheels move underneath you. Then, without thinking, you steer back again to stay on the path.
这和蹬着自行车一样。在整个骑行过程中你总是在不断的做调整。如果你朝右边倒了，潜意识里你就会朝左边倾斜一些以使车轮在你脚下移动。然后，不用想你又回到了路径上。
This “wobbling” is perfectly normal. It is more obvious among beginners (mostly children) who wobble around quite a lot, but it may be almost imperceptible in an expert cyclist. Nevertheless, these little wobbles are all part of the process and explain why walking – or riding – on a dead straight line is so hard because you can’t make those essential little side-to-side corrections.
这个“摇摆”是很正常的。在初学者中更为明显（大部分是儿童）会一直不停的摇摆，但是从专业骑手上基本上看不到任何摇摆。然而，这些小的摇摆都是学会骑车的过程的一部分，这也就解释了为什么行走，或者骑行，出一条笔直笔直的直线是不可能的，因为你很难一直不停的做出精确的矫正。
There are some really clever bits in bicycle design to make riding a bike easier, too. Most important is the fact that the steering column (the “head tube”) is tilted so that the front wheel makes contact with the ground at a point that lies behind where the steering axis intersects with the ground. The distance between these two points is called “the trail”.
有一些非常聪明的设计可以使自行车骑起来更容易。最重要的事实是，转向柱（“头管”）是倾斜的，因为前轮和地面的着力点，是在转向轴线与地面接触点之后的。这两点之间的距离称为“骑行痕迹”。
The trail really helps to stabilise a bike when you’re riding with no hands because when you lean to the right, say, the force at the contact point on the pavement will turn the front wheel to the right. This helps you to steer effortlessly and it allows for hands-free steering by leaning slightly left or right.
这个轨迹有助于你在骑行时保持平稳，当你骑车不扶把的时候，当你身体右倾斜时，在人行道上的接触点的力量会促使前轮转向右边。这有助于你将毫不费力的通过身体微倾来控制方向。
But people have built bikes with vertical head tubes and they are perfectly rideable, too. In fact, it’s quite hard to make a bike you can’t ride, and many have tried.
但人们也设计了一些垂直头管的自行车，而且也完全可以骑。事实想造一辆不能骑的自行车是很难的，很多人都尝试过了。
That’s because keeping a bike upright is largely to do with you and your brain – something that’s easy to prove. Try crossing your hands over, for example. You will not even be able to get started, and if you switch hands while you’re riding, be warned, you will fall off instantaneously – something that wouldn’t happen if it were the gyroscopic effect keeping you upright.
那是因为保持自行车直立主要是靠你和你的大脑来进行控制，而这点很容易证明。尝试交叉双手，你恐怕很难骑起来，即便是在骑行中间尝试换手，注意，你会马上摔倒-如果自行车是通过陀螺效应保持直立，就不会发生这样的情况。
Clowns and street performers ride bikes with reverse-geared steering. It takes months of practice to learn how to ride a bike like this, and it’s all about unlearning how to ride a normal bike. It’s amazing how the brain works.
小丑和街头艺人骑反向齿轮转向的自行车。要花几个月才能达到这样的水平，需要你把骑普通自行车的方法都忘掉。大脑的工作能力令人惊讶。
But what about the gyroscopic effect I referred to earlier? Surely it helps a bit? Well, no it doesn’t … unless you’re going pretty fast. There is a well-known demonstration that seems to show how a bike wheel is really affected by the gyroscopic effect but if you do the sums you can show that the effect is nowhere near strong enough to hold you up when you’re riding a bike.
那么我之前提到的陀螺效应呢？难道不能起作用么？嗯，并不能，除非你骑得特别快。有一个著名例子显示了陀螺效应在车轮上是如何发生作用的，但是如果你自己算算你就会发现那个效果远不足以支持你骑自行车。
To prove that the gyro effect is unimportant I built a bike with a second, counter-rotating front wheel. I’m not the first to have done this – David Jones built one in 1970. We both had the same idea. Essentially, the backward spinning wheel cancels out the gyroscopic effect of the front wheel, proving that it doesn’t matter and that the only thing keeping you upright is your brain. It’s also a really fun experiment that anyone can do.
为了证明陀螺效应不重要的，我造了一辆拥有第二个反旋转前轮的自行车。我不是第一个这样做的人，琼斯戴维（David Jones）早在1970年就造过了。我们的想法一样。基本上来说，反旋转的轮子将正向旋转的轮子产生的陀螺效应抵消，证明了陀螺效应并不重要，而真正使你能够直立的是你的大脑。这个实验非常有趣，大家都可以尝试。
So what’s the best way to learn to ride? Well, watching children learning to ride with trainer wheels distresses me because every time one of the stabilisers touches the ground it is an unlearning experience. To cycle, your brain has to learn to wobble, so take off the trainer wheels – and the more you wobble the quicker you’ll learn. Cycling really is all in the mind.
那么，最好的学骑自行车的方法是什么呢？嗯，看小孩子们用训练专用的自行车学习让我很苦恼，因为每一次保持平衡训练轮着地的时候就意味着又白学了。要想学会骑自行车，你的大脑必须要学会摇摆，所以把训练轮子拆除吧，摇摆的越厉害你就学得越快。骑自行车的诀窍真的都在你的大脑中。
