From 97b5ae1e969e810f620864feb24644be7dce2005 Mon Sep 17 00:00:00 2001 From: Paul Riseborough Date: Tue, 15 Jun 2021 20:26:42 +1000 Subject: [PATCH] EKF: Fix derivation comments for drag fusion --- EKF/python/ekf_derivation/main.py | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/EKF/python/ekf_derivation/main.py b/EKF/python/ekf_derivation/main.py index 768e9f5432..44155332bb 100755 --- a/EKF/python/ekf_derivation/main.py +++ b/EKF/python/ekf_derivation/main.py @@ -248,8 +248,12 @@ def body_frame_accel_observation(P,state,R_to_body,vx,vy,vz,wx,wy): # Use this nonlinear model for the prediction in the implementation only # It uses a ballistic coefficient for each axis and a propeller momentum drag coefficient - # accXpred = -sign(vrel[0]) * 0.5*rho*vrel[0]*(vrel[0]/BCoefX + MCoef) # predicted acceleration measured along X body axis - # accYpred = -sign(vrel[1]) * 0.5*rho*vrel[1]*(vrel[1]/BCoefY + MCoef) # predicted acceleration measured along Y body axis + # + # accXpred = -sign(vrel[0]) * vrel[0]*(0.5*rho*vrel[0]/BCoefX + MCoef) # predicted acceleration measured along X body axis + # accYpred = -sign(vrel[1]) * vrel[1]*(0.5*rho*vrel[1]/BCoefY + MCoef) # predicted acceleration measured along Y body axis + # + # BcoefX and BcoefY have units of Kg/m^2 + # Mcoef has units of 1/s # Use a simple viscous drag model for the linear estimator equations # Use the the derivative from speed to acceleration averaged across the