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9 - 8 - Autonomous Driving (7 min).srt
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In this video, I'd like to
在这段视频中
(字幕整理:中国海洋大学 黄海广,[email protected] )
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show you a fun and historically
我想向你介绍一个具有历史意义的
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important example of Neural Network Learning.
神经网络学习的重要例子
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00:00:06,720 --> 00:00:09,300
Of using a Neural Network for autonomous driving
那就是使用神经网络来实现自动驾驶
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00:00:09,870 --> 00:00:12,430
that is getting a car to learn to drive itself.
也就是说使汽车通过学习来自己驾驶
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00:00:13,810 --> 00:00:14,980
The video that I
接下来我将演示的
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showed a minute, was something
这段视频
8
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that I've gotten from Dean Pomilieu,
是我从 Dean Pomerleau那里拿到的
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00:00:18,470 --> 00:00:20,000
who Colleague who works
他是我的同事
10
00:00:20,260 --> 00:00:22,000
out in Carnegie Mellon University out
任职于美国东海岸的
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on the east coast of the United States,
卡耐基梅隆大学
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00:00:24,460 --> 00:00:25,310
and in part of the
在这部分视频中
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00:00:25,350 --> 00:00:27,980
video you see visualizations like
你就会明白可视化技术到底是什么
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00:00:28,230 --> 00:00:29,930
this, and what I should tell you what the visualization
在看这段视频之前
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00:00:30,080 --> 00:00:31,170
looks like before starting to
我会告诉你可视化技术是什么
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00:00:31,260 --> 00:00:32,830
video. Down here
在下面
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on the lower left is the
也就是左下方
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view seen by the car
就是汽车所看到的
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of what's in front of it
前方的路况图像
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00:00:37,840 --> 00:00:38,980
and so here you know, you will kind
在图中你依稀能看出
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of see you know, a road that's
一条道路
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maybe going a bit to
朝左延伸了一点
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the left and going a little bit to
又向右了一点
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the right, and up
然后上面的这幅图
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here on top, this
你可以看到一条
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first horizontal bar shows the
水平的菜单栏
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direction selected by the
显示的是驾驶操作人
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human driver and is the
所选择的方向
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location of this bright
就是这里的
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white band that shows the
这条白亮的区段
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steering direction selected by the
显示的就是
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human driver, where, you
人类驾驶者选择的方向
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know, here, far to the left
比如 最左边的区段
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corresponds to steering hard left;
对应的操作就是向左急转
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00:01:03,910 --> 00:01:05,180
here corresponds to steering hard
而最右端则对应
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to the right; and so
向右急转的操作
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this location, which is a
因此 稍微靠左的区段
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little bit to the left,
也就是这里
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a little bit left of
中心稍微向左一点的位置
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center, means that the human
则表示在这一点上
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driver, at this point, was
人类驾驶者的操作是
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steering slightly to the left. A
慢慢的向左拐
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nd this second part here
这幅图的第二部分
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corresponds to the steering
对应的就是
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direction selected by the
学习算法选出的行驶方向
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learning algorithm; and again, the
并且 类似的
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location of this sort
这一条白亮的区段
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of white band, means the
显示的就是
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neural network was here, selecting
神经网络在这里
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a steering direction just slightly to
选择的行驶方向
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the left and in fact,
是稍微的左转 并且实际上
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before the neural network starts
在神经网络开始
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learning initially, you
学习之前
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see that the network outputs a
你会看到网络的输出是
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grey band, like a
一条灰色的区段
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grey uniform, grey band throughout
就像这样的一条灰色区段
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this region, so the uniform
覆盖着整个区域 这些均称的
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grey fuzz corresponds to the
灰色区域显示出
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neural network having been randomly
神经网络已经随机初始化了
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00:01:44,450 --> 00:01:46,180
initialized, and initially having
并且初始化时
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no idea how to
我们并不知道 汽车如何行驶
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drive the car, or initially having
或者说
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no idea what direction to steer in.
我们并不知道所选行驶方向
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And it's only after it's learned
只有在学习算法运行了
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for a while that it will then start
足够长的时间之后
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to output like a solid white
才会有这条白色的区段
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band in just a small
出现在整条灰色区域之中
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part of the region corresponding
显示出一个具体的
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to choosing a particular steering direction.
行驶方向
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And that corresponds to when a neural network.
这就表示神经网络算法
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00:02:05,340 --> 00:02:06,890
Becomes more confident in selecting, you know,
在这时候已经选出了一个
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00:02:08,080 --> 00:02:09,250
a and in one
明确的行驶方向
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location rather than outputting
不像刚开始的时候
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a sort of light gray
输出一段模糊的浅灰色区域
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00:02:13,300 --> 00:02:14,570
fuzz, but instead outputting
而是输出
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00:02:14,970 --> 00:02:17,010
a white band that's
一条白亮的区段
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more constantly selecting one steering direction.
表示已经选出了明确的行驶方向
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Alban is a system
ALVINN (Autonomous Land Vehicle In a Neural Network)
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of artificial neural networks, that learns to steer
是一个基于神经网络的智能系统
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by watching a person drive. Alban
通过观察人类的驾驶来学习驾驶
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is designed to control the
ALVINN能够控制NavLab载具——
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tube a modified army
一辆改装版军用悍马
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Humvee who could put
这辆悍马装载了
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sensors, computers and actuators
传感器 计算机和驱动器
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for autonomous navigation experiments.
用来进行自动驾驶的导航试验
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The initial spec in
实现ALVINN功能的第一步
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configuring Alban is training in
是对它进行训练
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the training the person drives
也就是训练一个人驾驶汽车
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to be a car while Alban watches.
然后让ALVINN观看
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Once every two seconds, Alban
ALVINN每两秒
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digitizes a video image
将前方的路况图生成一张数字化图片
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of the road ahead, and records the person's steering direction.
并且记录驾驶者的驾驶方向
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This training image is reduced
得到的训练集图片
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00:03:13,560 --> 00:03:15,260
in resolution to 30 by
被压缩为30x32像素
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32 pixels and provided
并且作为输入
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as input to Alban's three-layer
提供给ALVINN的三层
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network.
神经网络
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Using the back propagation learning algorithm; Alban
通过使用反向传播学习算法
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00:03:25,370 --> 00:03:26,590
is training to output the same
ALVINN会训练得到一个
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00:03:26,940 --> 00:03:28,450
steering direction as the
与人类驾驶员操纵方向
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human driver for that image
基本相近的结果
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Initially, the network's steering response is random.
一开始 我们的网络选择出的方向是随机的
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After about two minutes of
大约经过两分钟的训练后
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training, the network learns
我们的神经网络
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to accurately imitate the steering
便能够准确地模拟
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reactions of the
人类驾驶者的
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human driver. This same
驾驶方向
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training procedure is repeated for other road types.
对其他道路类型 也重复进行这个训练过程
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00:04:09,940 --> 00:04:11,680
After the networks have been trained the
当网络被训练完成后
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operator pushes the run
操作者就可按下运行按钮
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switch and often begins
车辆便开始行驶
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00:04:15,050 --> 00:04:20,380
driving. 12 times
每秒钟ALVINN生成
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per second, Alban digitizes an
12次数字化图片
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image and feeds it to its neural networks.
并且将图像传送给神经网络进行训练
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Each network, running in parallel,
多个神经网络同时工作
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00:04:35,930 --> 00:04:38,140
produces a steering direction and a measure of it's
每一个网络都生成一个行驶方向
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confidence in its response.
以及一个预测自信度的参数
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The steering direction
预测自信度最高的
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from the most confident network.
那个神经网络得到的行驶方向
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00:04:52,340 --> 00:04:53,650
In this case, the network trained
比如这里 在这条单行道上训练出的网络
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for the one-lane road is used to control the vehicle.
将被最终用于控制车辆方向
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00:05:04,750 --> 00:05:07,840
Suddenly, an intersection appears ahead
车辆前方突然出现了
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00:05:08,310 --> 00:05:09,350
of the vehicle.
一个交叉十字路口
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00:05:23,090 --> 00:05:24,450
As the vehicle approaches the intersection,
当车辆到达这个十字路口时
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00:05:25,680 --> 00:05:27,740
the confidence of the one-lane network decreases.
我们单行道网络对应的自信度骤减
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00:05:38,070 --> 00:05:40,030
As it crosses the intersection, and
当它穿过这个十字路口时
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00:05:40,130 --> 00:05:41,160
the two-lane road ahead comes
前方的双车道将进入其视线
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00:05:41,440 --> 00:05:44,610
into view, the confidence of the two-lane network rises.
双车道网络的自信度便开始上升
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00:05:51,260 --> 00:05:53,000
When it's confidence rises, the two-lane
当它的自信度上升时 双车道的网络
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00:05:53,420 --> 00:05:54,630
network is selected to steer,
将被选择来控制行驶方向
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safely guiding the vehicle
车辆将被安全地引导
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00:05:57,380 --> 00:05:59,030
into it's lane, on the two-lane road.
进入双车道路
133
00:06:05,400 --> 00:06:06,670
So that was autonomous
这就是基于神经网络的
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00:06:07,010 --> 00:06:09,790
driving using a neural network. Of course, there are more
自动驾驶技术 当然 我们还有很多
135
00:06:10,150 --> 00:06:11,070
recently more modern attempts
更加先进的试验
136
00:06:11,910 --> 00:06:14,000
to do autonomous driving in a few properties, in
来实现自动驾驶技术
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the U.S., in Europe, and so on.
在美国 欧洲等一些国家和地区
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They're giving more robust driving
他们提供了一些比这个方法
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controllers than this, but I
更加稳定的驾驶控制技术
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think it's still pretty remarkable and
但我认为 使用这样一个简单的
141
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pretty amazing how a simple
基于反向传播的神经网络
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neural network trained with back-propagation
训练出如此强大的自动驾驶汽车
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can, you know, actually learn to drive a car somewhat well.
的确是一次令人惊讶的成就