Hello, I am trying to simulate heavy (>15 kg) electric quadplanes in Ardupilot SITL and want to change battery and propeller parameters to better represent the vehicle I have in-person. I found the SITL.cpp file for battery parameterization, but cannot find the _effective_prop_area definition anywhere. Where can I find this value at? Additionally, are there any other parameters you suggest modifying to better represent heavy electric quadplanes in SITL?
Thank you!
you can get the following formulas somewhere in EvaluateMotorModel.cpp
float ref_air_density = frame.public_get_air_density(frame.get_ref_alt());
float hover_thrust = frame.get_mass() * GRAVITY_MSS;
float hover_power = frame.get_ref_current() * frame.get_ref_voltage();
float hover_velocity_out = 2 * hover_power / hover_thrust;
float effective_disc_area = hover_thrust / (0.5 * ref_air_density * sq(hover_velocity_out));
float effective_prop_area = effective_disc_area / frame.get_num_motors();
all relative values in SIM_Frame.h, effective_prop_area will be _effective_prop_area and just update them to see if it works.
good luck
Sean