当前NASA工程师结合运动跟踪红外（IR）摄像头，6个步进电动机，钓鱼线和飞镖板时，您会得到什么？这很容易！一个很棒的制造商项目：一个飞镖板，它每次都会拦截飞镖并为您提供牛看。

According to边缘，马克·罗伯（Mark Rober）建造了一个自定义飞镖板“…that can track a dart through the air and perfectly position itself to let the dart hit a bull’s-eye no matter where it’s thrown…”

Well, it wasn’t那简单的。YouTube个性罗伯在三年的时间里，可以创建自动的牛赛式dartboard。但它是真的有创造力的。

罗伯（Rober）在描述该项目时说，系统的主要部分：计算以预测飞镖在投掷后将要降落的地方，然后将飞镖板移至该计算的位置。这些步骤必须在不到十分之秒的时间内完成，因为如果您站在监管距离处，那是关于飞镖从手中到飞镖需要多长时间的时间。

Calculating the desired location

自动飞镖系统依靠运动跟踪来确定飞镖的轨迹。为此，Rober使用了6个Vicon IR摄像机。为了简化图像，飞镖配备了IR反射器。这意味着图像捕获飞镖，而不是周围环境中的所有“视觉噪音”。事实证明，当系统在不完美光线的栏中设置时，这很有帮助。

Since each camera has 4k resolution and captures an image 260 times per second, the image capture system captures 6.24 million pixels per second. This data is streamed to a computer which then calculates the trajectory of the dart and the predicted location when it reaches the plane of the dartboard.

“Now that we have the XYZ position of the dart as it travels through the air, we use someMATLABcode to then predict where it will land,” states Rober. He estimates that it takes 200 ms to calculate the end location of the dart.

垂直位置计算考虑了飞镖将传播的抛物线路径。水平位置基于简单的线方程。虽然这很简单，但系统需要亚毫米的精度。

将飞镖板移至计算的位置

Once you know where the dart is headed, you must get the dartboard there in less than 200 ms. The MATLAB code translates the final XYZ location into commands for the motor system that moves the dartboard.

The board is mounted on two linear sliders, enabling it to move both vertically and horizontally. There are 6 stepper motors used to “pull” the dartboard to the desired location, and that’s where the fishing line comes in. The motors pull the dartboard along the sliders with fishing line attached to the back of the board. When one motor pulls the board, the motor on the other side lets out the fishing line at the same rate.

The computer signals the location to an Arduino-compatible board, which in turn, signals each motor whether to wind up the fishing line or unwind the spool it is controlling. To achieve this accuracy,regression analysisin MATLAB helps the system refine the positioning of the dartboard up to 100 times during its 0.4-second flight.

Check out the full video:

Yes, the system does require a specialized dart. There’s also an “evil twin dart” which moves the dartboard in the opposite direction of the calculated trajectory. That dart is perfect for your opponent when you really want to beat them at darts. It’s also the perfect dart to hand over to Jimmy Kimmel on live TV, which is exactly what Mark Rober did!

如果您想看到其他MATLAB/基于Arduino的项目，查看MATLAB Maker Community.