TED演讲:一个能防止人群踩踏事件的救生发明(4)（在线收听）

So we decided to design a cover for the sensor so that people don't have to worry what it is on the ground.

所以我们决定给传感器加个盖板，这样人们就不用担心放在地上的是什么了。

So after some experimentation, we decided to use an industrial sensor,

在经过几次实验后，我们打算使用工业级的传感器，

used as a safety trigger in hazardous areas as the sensor, and a black neoprene rubber sheet as the cover.

这种传感器在危险地区被用作安全触发器，并用一块黑色的氯丁橡胶板作为盖子。

Now, another added benefit of using black rubber was that dust naturally accumulates over the surface,

另一个使用黑色橡胶板的好处是，灰尘会自然聚集在表面，

eventually camouflaging it with the ground.

最终伪装成土地表面的样子。

We also had to make sure that the sensor is no higher than 12 millimeters.

我们还需要确保传感器的厚度不能超过12毫米。

Otherwise, people might trip over it, which in itself would cause stampedes. We don't want that.

否则人们会被绊倒，这本身就会引起踩踏。我们可不想这样。

So we were able to design a sensor which was only 10 millimeters thick.

所以我们设计了只有10毫米厚的传感器。

Now the data is sent to the server in real time,

现在数据实时传回服务器了，

and a heat map is plotted, taking into account all the active devices on the ground.

热点图生成了，基于地面这些所有的活跃设备。

The authorities could be alerted if the crowd movement slowed down or if the crowd density moved beyond a desired threshold.

政府部门就可以知道人群慢了下来，或者人群密度超过了期望的阀值。

We installed five of these mats in the Nashik Kumbh Mela 2015,

我们在2015年纳西克大壶节上安装了5块传感垫子，

and counted over half a million people in 18 hours,

在18个小时内统计出了超过50万人，

ensuring that the data was available in real time at various checkpoints, ensuring a safe flow of people.

确保了不同采集点数据的可用性和实时性，确保了人流的安全。