【钠瞳 Sodium Pupil】二：怎么做

二、怎么做

2.1 核心只有一个动作：把"看"和"认"拆开

常规相机只有两档：拍，或者不拍。我们把它拆成四档：

关键那句话是：看很便宜，认很贵。

一次低分辨率瞥眼约 1 mWh，一次完整识别加回传约 124 mWh，相差两个数量级。只要能把大量误触发挡在"瞥眼"这一层，省下的电就可以全部留给真正值得的事件。

常规相机做不到这一点，因为它要么在睡，要么在用力看，中间没有那一档。

2.2 AI 做什么：决定哪一件事值得

"值得"由场景定、由人定：

• 夜里十点一片叶子在晃——不值得认；
• 凌晨三点一只动物在饮水点——值得认，但不一定值得马上发；
• 黄昏六点半，一个人背着东西往山里走——值得认，而且值得立刻发。

AI 在每个时刻回答同一个问题：这块电花在哪个动作上，总收益最高。同时必须保证：不管怎么花，都不能把自己花死到明天早上。

2.3 钠电做什么：三件事，别多说

能量从哪来、怎么才能不死，这是钠电的位置。只说三件事：

1. 冷的时候放得出——-40℃ 时钠电仍有 55% 可用，磷酸铁锂只剩 22%；
2. 冷的时候充得进——磷酸铁锂 0℃ 以下禁止充电，钠电可充到 -20℃。阴雪之后能不能回补，差在这里；
3. 放空了不报废——钠电可放电至 0V，放空一个冬天，太阳回来还能再用。

这三件事加起来，才叫"能活下来"。而 AI 要能好好干活，前提是它得先活着。

II. How It Works

2.1 The core move: separate "looking" from "identifying"

A conventional camera has only two modes: shot, or no shot. We split this into four:

The key line is: looking is cheap, identifying is expensive.

A low-resolution peek costs about 1 mWh, while a full identification plus transmission costs about 124 mWh — two orders of magnitude apart. As long as the vast majority of false triggers can be stopped at the "peek" stage, all the saved energy can be reserved for events that truly deserve it.

A conventional camera cannot do this, because it is either asleep or looking hard; that middle level simply does not exist in its design.

2.2 What the AI does: decide which event is worth it

What counts as "worth it" is defined by the scenario and by the people who operate it:

• A leaf trembling at ten at night — not worth identifying;
• An animal at a watering point at three in the morning — worth identifying, but not necessarily worth sending immediately;
• At half past six in the evening, a person walking into the mountains carrying something — worth identifying, and worth sending at once.

At every moment the AI answers the same question: which action should this unit of energy be spent on to maximise the total return? It must simultaneously guarantee one thing: however the energy is spent, the device must not spend itself to death before next morning.

2.3 What the sodium-ion battery does: three things, no more

Where the energy comes from and how the device stays alive is the job of the battery. Three things only:

1. It can output power when cold — at -40℃ a sodium-ion cell still delivers 55% of its capacity, while LFP delivers only 22%;
2. It can take charge when cold — LFP is forbidden to charge below 0℃, while sodium-ion can charge down to -20℃. Whether the device can recover after a snowstorm depends on exactly this;
3. It does not become scrap when fully drained — a sodium-ion cell can be discharged to 0 V; after a whole winter at empty, it still works when the sun returns.

Only when these three are added together does "staying alive" become meaningful. And the AI can only do its job well on the premise that the device is still alive.