关于控制器部分的问题 about fast-drone-250

[dongdongbh]

Fast-Drone-250/src/realflight_modules/px4ctrl/src/controller.cpp

Lines 41 to 42 in 8ff6427

	roll = (des_acc(0) * sin - des_acc(1) * cos )/ param_.gra;
	pitch = (des_acc(0) * cos + des_acc(1) * sin )/ param_.gra;

我大概理解这两行并不是直接按微分平坦算的，而是在算外环（位置速度反馈和加速度前馈）的给内环串级控制的输入，这里实际上应该是把航向旋转影响消除后应该给内环的输入（实际上是外环输出通过旋转航向投影到pitch和roll轴以便姿态控制）。应该是这个矩阵乘以［a0, a1, a2］。
这里gamma是航向角，不过我推出来roll = ( des_acc(1) * cos-des_acc(0) * sin ) ，roll和作者的方向相反，可能这里和roll的方向定义有关？

这里除以重力实际上应该是一种简单有点粗暴的归一化（反正有PID）参数，所以都无所谓的。具体还请作者指正。

另外关于Recursive least squares algorithm with vanishing memory

Fast-Drone-250/src/realflight_modules/px4ctrl/src/controller.cpp

Line 135 in 8ff6427

P_ = (1 - K * thr) * P_ / rho2_;

为什么要除 rho2_，原始的Recursive least squares algorithm这里似乎不需要除

[dongdongbh]

@FaboNo Recursive Least Squares Method

[dongdongbh]

debug_msg_只是为了debug方便而发布的topic，最终油门和姿态给了飞控，控制是位置和速度的P控制外加加速度前馈给到姿态控制器做串级

[FaboNo]

@dongdongbh the equations are coming from which paper?
方程式来自哪篇论文？

[Nikanbaturu]

@dongdongbh 您好！请问可以把controller理解为位置控制器吗？而且没太看懂对debug_msg_赋值的意义，是为了存储计算得到的期望值将其作为内级控制器的输入吗？

[Nikanbaturu]

@dongdongbh 感谢您的回答，那controller这部分的位置控制算法是否可以替换成其他的呢？

[dongdongbh]

可以

[dongdongbh]

Finally understand it by reading their PPT

这里实际上用了小角度假设， 所以理论上还是SE3控制好一些，具体可参考

Minimum snap trajectory generation and control for quadrotors

[FaboNo]

@dongdongbh oh very interesting, where did you find the ppt?

[dongdongbh]

Here is a video with this ppt talking about these stuff, but in Chinese.

[karjalv]

另外关于Recursive least squares algorithm with vanishing memory

Fast-Drone-250/src/realflight_modules/px4ctrl/src/controller.cpp

Line 135 in 8ff6427

P_ = (1 - K * thr) * P_ / rho2_;

为什么要除 rho2_，原始的Recursive least squares algorithm这里似乎不需要除

@dongdongbh Have you found any reason for this division with rho2_ ? I've been wondering the same thing.

[bulingda]

另外关于Recursive least squares algorithm with vanishing memory

Fast-Drone-250/src/realflight_modules/px4ctrl/src/controller.cpp

Line 135 in 8ff6427

P_ = (1 - K * thr) * P_ / rho2_;

为什么要除 rho2_，原始的Recursive least squares algorithm这里似乎不需要除

@dongdongbh Have you found any reason for this division with rho2_ ? I've been wondering the same thing.

Hello, do you understand the meaning of this formula?