Moment of inertia at SITL

hiroyuki405 · August 21, 2017, 6:53am

hi guys
I am experimenting with MultiCopter’s SITL.
Therefore, I would like to perform a simulation with changing the moment of inertia
Please tell me how to change the moment of inertia of SITL

Mahdi_Joodi · January 8, 2023, 3:31pm

hi @hiroyuki405 @tridge
I am looking for the same thing. Have come up with an answer?

tridge · January 9, 2023, 9:04pm

There is an example model for you to work with here:

github.com

ArduPilot/ardupilot/blob/master/Tools/autotest/models/Callisto.json

# Callisto model, see https://www.freespaceoperations.com.au/

{
    # total vehicle mass
    "mass" : 32.5,

    # vehicle diameter
    "diagonal_size" : 1.325,

    # the ref parameters should be taken from a test
    # with the copter flying at constant speed in zero wind. This is used
    # to estimate the drag coefficient
    "refSpd" : 25.0,    # m/s
    "refAngle" : 30.0,   # degrees
    "refVoltage" : 46.9, # volts
    "refCurrent" : 65.36, # Amps
    "refAlt" : 26,       # meters AMSL
    "refTempC" : 25,     # degrees C
    "refBatRes" : 0.024, # BAT.Res from log

This file has been truncated. show original

When using sim_vehicle.py you would pass “-f Callisto” to select this model.
If you are using the MissionPlanner SITL button then it can also be selected, but it isn’t as easy.