将两个矢量风预测值通过卡尔曼滤波建模,融合为一个矢量风,的python实现
时间: 2024-03-01 22:51:15 浏览: 15
下面是一个简单的Python实现将两个矢量风通过卡尔曼滤波建模融合为一个矢量风的代码:
```python
import numpy as np
class KalmanFilter:
def __init__(self, n, m):
self.n = n
self.m = m
self.A = np.zeros((n, n)) # 状态转移矩阵
self.H = np.zeros((m, n)) # 观测矩阵
self.Q = np.zeros((n, n)) # 状态噪声协方差矩阵
self.R = np.zeros((m, m)) # 观测噪声协方差矩阵
self.P = np.zeros((n, n)) # 状态估计误差协方差矩阵
self.x = np.zeros((n, 1)) # 状态向量
def predict(self):
self.x = np.dot(self.A, self.x) # 预测状态
self.P = np.dot(np.dot(self.A, self.P), self.A.T) + self.Q # 预测误差协方差
def update(self, z):
y = z - np.dot(self.H, self.x) # 计算预测误差
S = np.dot(np.dot(self.H, self.P), self.H.T) + self.R # 计算卡尔曼增益
K = np.dot(np.dot(self.P, self.H.T), np.linalg.inv(S))
self.x = self.x + np.dot(K, y) # 更新状态
self.P = np.dot((np.eye(self.n) - np.dot(K, self.H)), self.P) # 更新误差协方差
def wind_vector_kalman_filter(x1, x2):
# 初始化卡尔曼滤波器
kf = KalmanFilter(n=4, m=2)
dt = 1.0 # 时间间隔
# 设置状态转移矩阵
kf.A[0, 0] = kf.A[1, 1] = kf.A[2, 2] = kf.A[3, 3] = 1.0
kf.A[0, 2] = kf.A[1, 3] = dt
# 设置观测矩阵
kf.H[0, 0] = kf.H[1, 1] = 1.0
# 设置状态噪声协方差矩阵
kf.Q = np.eye(4) * 0.001
# 设置观测噪声协方差矩阵
kf.R = np.eye(2) * 0.1
# 初始化状态向量
kf.x[0, 0] = x1[0]
kf.x[1, 0] = x1[1]
kf.x[2, 0] = x2[0]
kf.x[3, 0] = x2[1]
# 初始化误差协方差矩阵
kf.P = np.eye(4) * 1000.0
# 迭代预测和更新
for i in range(1, len(x1)):
kf.A[0, 2] = kf.A[1, 3] = dt # 更新状态转移矩阵
kf.predict()
kf.update(np.array([x1[i], x2[i]]))
return kf.x[0:2, :].flatten(), kf.x[2:4, :].flatten()
def wind_kalman_filter(v1, v2):
# 融合两个矢量风
v = np.concatenate((v1, v2), axis=1)
# 初始化卡尔曼滤波器
kf = KalmanFilter(n=8, m=2)
dt = 1.0 # 时间间隔
# 设置状态转移矩阵
kf.A[0, 0] = kf.A[1, 1] = kf.A[2, 2] = kf.A[3, 3] = kf.A[4, 4] = kf.A[5, 5] = kf.A[6, 6] = kf.A[7, 7] = 1.0
kf.A[0, 2] = kf.A[1, 3] = kf.A[4, 6] = kf.A[5, 7] = dt
# 设置观测矩阵
kf.H[0, 0] = kf.H[2, 1] = kf.H[4, 2] = kf.H[6, 3] = 1.0
kf.H[1, 0] = kf.H[3, 1] = kf.H[5, 2] = kf.H[7, 3] = 1.0
# 设置状态噪声协方差矩阵
kf.Q = np.eye(8) * 0.001
# 设置观测噪声协方差矩阵
kf.R = np.eye(2) * 0.1
# 初始化状态向量
kf.x[0, 0] = v1[0]
kf.x[1, 0] = v1[1]
kf.x[2, 0] = v2[0]
kf.x[3, 0] = v2[1]
kf.x[4, 0] = 0.0
kf.x[5, 0] = 0.0
kf.x[6, 0] = 0.0
kf.x[7, 0] = 0.0
# 初始化误差协方差矩阵
kf.P = np.eye(8) * 1000.0
# 迭代预测和更新
for i in range(1, len(v1)):
v1_hat, v2_hat = wind_vector_kalman_filter(v[:, i-1], v[:, i]) # 对两个矢量风进行卡尔曼滤波
kf.A[0, 2] = kf.A[1, 3] = kf.A[4, 6] = kf.A[5, 7] = dt # 更新状态转移矩阵
kf.predict()
kf.update(np.concatenate((v1_hat.reshape(-1, 1), v2_hat.reshape(-1, 1)), axis=0))
return kf.x[0:4, :].flatten()
```
其中,`v1`和`v2`分别表示两个矢量风的预测值,返回值为经过卡尔曼滤波后的融合后的矢量风预测值。在实现中,先对两个矢量风分别进行卡尔曼滤波,然后再将滤波后的结果作为观测量,通过卡尔曼滤波器进行融合。