解读IMU理论

圆点博士跟我学

英文来自http://www.starlino.com/imu_guide.html的IMU Theory and Experiments
楼主和大家一起来解读下该文章的精华。

圆点博士跟我学

英文原文：
I'll try try to cover few basic but important topics in this article:

- what does an accelerometer measure
- what does a gyroscope (aka gyro) measure
- how to convert analog-to-digital (ADC) readings that you get from these sensor to physical units (those would be g for accelerometer, deg/s for gyroscope)
- how to combine accelerometer and gyroscope readings in order to obtain accurate information about the inclination of your device relative to the ground plane

google翻译：
我会尽力试图掩盖在这篇文章中的一些基本的，但重要的主题：

- 这是什么加速度计测量
- 这是什么一个陀螺仪（又名陀螺仪）测量
- 如何转换模拟到数字（ADC），你得到的读数从这些传感器的物理单位（那些将G的加速度计，陀螺仪度/秒）
- 如何结合加速度计和陀螺仪的读数，以获得准确的信息，关于您的移动设备的相对的倾斜到地面平面

圆点博士跟我学

英文原文：
Throughout the article I will try to keep the math to the minimum. If you know what Sine/Cosine/Tangent are then you should be able to understand and use these ideas in your project no matter what platform you're using Arduino, Propeller, Basic Stamp, Atmel chips, Microchip PIC, etc. There are people out there who believe that you need complex math in order to make use of an IMU unit (complex FIR or IIR filters such as Kalman filters, Parks-McClellan filters, etc). You can research all those and achieve wonderful but complex results. My way of explaining things require just basic math. I am a great believer in simplicity. I think a system that is simple is easier to control and monitor, besides many embedded devices do not have the power and resources to implement complex algorithms requiring matrix calculations.

google翻译：
在整篇文章中，我会尽量保持最低的数学。如果你知道什么正弦/余弦/正切，那么你应该能够理解和使用这些观念在你的项目中，无论你使用什么样的平台Arduino的螺旋桨，基本邮票，爱特梅尔芯片，Microchip的PIC等人在那里谁相信你为了利用惯性测量单元（复数FIR或IIR滤波器，如公园麦克莱伦卡尔曼滤波器，滤波器等）需要复杂的数学。你可以研究，实现所有这些美好的，但复杂的结果。我解释事情的方式，只需要基本的数学。我是一个伟大的信徒简单。我想简单的一个系统，是比较容易控制和监视，除了许多嵌入式设备没有足够的权力和资源，实现复杂的算法需要矩阵计算。

圆点博士跟我学

英文原文和google翻译：

Part 1. AccelerometerTo understand this unit we'll start with the accelerometer. When thinking about accelerometers it is often useful to image a box in shape of a cube with a ball inside it. You may imagine something else like a cookie or a donut , but I'll imagine a ball:

要理解这个单元，我们将开始与加速度计。当思考加速度计，它往往是图像框在一个立方体形状的球里面有用。您可能想象像一个cookie或甜甜圈别的东西，但我会想象一个球：

If we take this box in a place with no gravitation fields or for that matter with no other fields that might affect the ball's position – the ball will simply float in the middle of the box. You can imagine the box is in outer-space far-far away from any cosmic bodies, or if such a place is hard to find imagine at least a space craft orbiting around the planet where everything is in weightless state . From the picture above you can see that we assign to each axis a pair of walls (we removed the wall Y+ so we can look inside the box). Imagine that each wall is pressure sensitive. If we move suddenly the box to the left (we accelerate it with acceleration 1g = 9.8m/s^2), the ball will hit the wall X-. We then measure the pressure force that the ball applies to the wall and output a value of -1g on the X axis.

如果我们把这个框在一个地方，没有引力领域或为此事与任何其他领域，可能会影响球的位置 - 球会简单地浮在中间的箱子。你可以想象盒子是在外太空远远离任何天体，或者至少是很难找到这样的地方想象飞船围绕地球轨道，这里的一切是在失重状态。从上面的图片中，你可以看到，我们分配给每个轴的一对壁（我们去掉墙Y +，所以我们可以看箱内）。试想一下，每个墙壁的压力敏感。如果我们突然移动框的左侧（加速加速度1G=9.8米/秒^ 2），球会打在墙上的X。然后，我们测量球的壁和在X轴上的输出值的1克适用于的压力。




Please note that the accelerometer will actually detect a force that is directed in the opposite direction from the acceleration vector. This force is often called Inertial Force or Fictitious Force . One thing you should learn from this is that an accelerometer measures acceleration indirectly through a force that is applied to one of it's walls (according to our model, it might be a spring or something else in real life accelerometers). This force can be caused by the acceleration , but as we'll see in the next example it is not always caused by acceleration.

请注意，加速度计将实际检测到的加速度向量的方向相反的方向的力被引导。这股力量往往被称为惯性力或虚构的部队。有一件事你应该学习的是一个加速度计测量加速度间接通过力应用到它的墙壁之一（根据我们的模型，它可能是一个春天或别的东西，在现实生活中，加速度计）。这种力量可以由加速度引起的，但在下一个例子中，我们会看到它并不总是由加速度引起的。

zndz410

虽然不懂，还是要顶楼主辛苦了。

nhlijiaming

人工翻译吧, google翻译还真是接受不了........

疯狂的指头

嘿嘿 前排                                       

jin_tong

学习了，谢谢分享链接，楼主辛苦，坚持翻译完啊！顶

小农

谢谢分享~~~

哈勃

这个翻译有点类。。话说这网站以前去过，不过实在没有耐心去读。。