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当我把旋转矩阵的原理理解过后,逐渐意识到。做着一切的意义在哪里。。
郁闷了一天,感觉有了答案,还是应当沉下心来去理解才行,不能急躁.
我疑惑在,陀螺仪得到的就是三个轴的角速度积分直接就可以得到角度,那旋转矩阵在这里又有什么用处了?但是又觉得我这样的角度是不具有意义的,没有参考下得到的一切都是没有价值的。这似乎应该是一条普世的真理吧~~
然后....就豁然开朗了...mp6050集成加速度计和陀螺仪是有道理的,不知道大家想过没.怎么才知道参考坐标系了(大地坐标系)?现在就是加速度计的作用了,加速度计感知重力加速度,因此可以以重力加速度为z轴建立一个坐标系那么这就是大地坐标系了。可是现在我们通过陀螺仪获得的角速度是机体坐标系的,这个时候就是旋转矩阵的作用就出来了.我们知道在非惯性系中许多物理定律是不适用的。[ ψ θ φ] 表示的是从大地坐标系转换到机体坐标系的角度,所以机体坐标下的角速度转换到大地坐标的形式为
<出处在上一文中提到>
注意到变换矩阵中只涉及到θ,φ。因为偏航角是不影响姿态的平衡的.那么这里的θ,φ如何得到了?这就要利用加速度计,具体如何计算
我会在明天的更新中介绍.
这样我们就把陀螺仪的角速度转换到欧拉角的角速度了,特别注意而这并不是等价的,考虑到角度很小的情况下,比如近似水平时有
感觉今天的突破就在这里吧···越往后越艰难..感受到基础的不够..加油
English version
When i get the main idea of rotation matrix,i gradually puzzled about the meaning of
rotation matrix. I mean I don‘t know what the result represented.
After my daytime thinking,i realized that only you calm yourself down can you
grasp marrow .
The angle had known through Integral. Then,rotation matrix is no useful.Well, the
ideas come to me . The world comes to end without reference.
So,putting gyroscope and accelerometer makes sense. We can found a coordinate system
B and the the direction of the gravity as Z axis.We know B is geodetic coordinate
system.But the angle we get is under body coordinate system.And [ ψ θ φ] is the
angle from geodetic coordinate system to body coordinate system .We assume [r q p]
are the z/y/x rotating angular velocity in body coordinate system. So,the heading
angle velocity are correspond to [r q p].The relaionship were in the picture.
noticed that only θ,φ are involved .For the heading angle have no effect in gesture
calculateing.The method of geting θ,φ by accelerometer will be introduced
tomorrow.
After that, the angular velocity of gyroscope were change into Euler angle
velocity.Specially , when four axis close to horizontal ,we have a relationship.like
this.
thanks....good night....never give up.
前进中的迷茫-the confusion in my way
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原文地址:http://www.cnblogs.com/bigben/p/4264945.html