From cf1c6a8b84fc99f07a895665004dd4a18210121e Mon Sep 17 00:00:00 2001
From: bresch <[brescianimathieu@gmail.com](mailto:brescianimathieu@gmail.com)>
Date: Wed, 11 Oct 2023 13:31:40 +0200
Subject: [PATCH] ekf2-derivation: remove old wind covariance derivation

---
 .../EKF/python/wind_cov_init/derivation.py    | 67 -------------------
 1 file changed, 67 deletions(-)
 delete mode 100644 src/modules/ekf2/EKF/python/wind_cov_init/derivation.py

diff --git a/src/modules/ekf2/EKF/python/wind_cov_init/derivation.py b/src/modules/ekf2/EKF/python/wind_cov_init/derivation.py
deleted file mode 100644
index c79cfd1aed..0000000000
--- a/src/modules/ekf2/EKF/python/wind_cov_init/derivation.py
+++ /dev/null
@@ -1,67 +0,0 @@
-#!/usr/bin/env python2
-# -*- coding: utf-8 -*-
-"""
-Created on Tue Oct 29 14:11:58 2019
-
-@author: roman
-"""
-
-from sympy import *
-
-################## Here are the variables you can change to see the effects on the cov matrix ###########################
-yaw_init =  0.5
-
-# ground speed in body frame (comes from ekf2)
-groundspeed_body_x_init = 5
-groundspeed_body_y_init = 5
-
-# true airspeed measured by pitot tube
-V_init = 7
-
-# heading variance
-R_yaw_init = rad(15.0)**2
-
-# sideslip variance
-R_beta_init = rad(15.0)**2
-
-# True airspeed measurement variance
-R_tas_init = 1.4**2
-
-#########################################################################################################################
-
-# define symbols: true airspeed, sidslip angle,
-V, beta, yaw, groundspeed_body_x, groundspeed_body_y = symbols('V beta yaw vx_body vy_body')
-R_tas, R_beta, R_yaw = symbols('R_tas R_beta R_yaw')
-
-
-# body x/y component of relative wind vector ( V is what the airspeed sensor measures)
-Vx = V * cos(beta)
-Vy = V * sin(beta)
-
-
-# wind in body frame
-wind_body_x = groundspeed_body_x - Vx
-wind_body_y = groundspeed_body_y - Vy
-
-# wind in earth frame
-wind_n = cos(yaw) * wind_body_x - sin(yaw) * wind_body_y
-wind_e = sin(yaw) * wind_body_x + cos(yaw) * wind_body_y
-wind_earth = Matrix([wind_n, wind_e])
-
-# jacobian of earth wind vector with respect to states with known uncertainties
-G = wind_earth.jacobian([V, beta, yaw])
-
-# initial covariance matrix
-P = Matrix([[R_tas, 0, 0], [0, R_beta,0], [0,0,R_yaw]])
-
-# earth wind covariance matrix, assume 0 sideslip angle
-P_wind_earth = (G*P*G.T).subs([(beta, 0)])
-
-P_wind_earth_numeric = P_wind_earth.subs([(V, V_init),(yaw, yaw_init), (R_tas, R_tas_init), (R_yaw, R_yaw_init), (R_beta, R_beta_init)])
-P_wind_earth_numeric = P_wind_earth_numeric.subs([(groundspeed_body_x, groundspeed_body_x_init), (groundspeed_body_y, groundspeed_body_y_init) ])
-
-
-print('P[22][22] = ' + str(P_wind_earth_numeric[0,0]))
-print('P[22][23] = ' + str(P_wind_earth_numeric[0,1]))
-print('P[23][22] = ' + str(P_wind_earth_numeric[1,0]))
-print('P[23][23] = ' + str(P_wind_earth_numeric[1,1]))