Quadcopter Airframe

Step 3 of 5 in Model a Quadcopter Based on Parrot Minidrones

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You can use one of these two approaches to implement the airframe model.

Nonlinear Airframe

For a nonlinear airframe, the model computes gravity forces, profile drag, and the aerodynamic forces and moments.

The AC Model subsystem computes the total force using these equations:

Gravity: $$F=mg$$, where m is the quadcopter mass, and g is the acceleration due to gravity.

Profile drag: $$D=\frac{1}{2}\rho V^{2}S{C}_d$$, where ρ is the atmospheric density, V is the body velocity, S is the reference area, and C_d is the drag coefficient.

Aerodynamic forces and moments: Computed using the Multirotor block with the inclusion of flap effects.

The 6DOF (Euler Angles) block integrates the equations of motion of the vehicle to obtain the states at each time instant.

Set VSS_VEHICLE to 1 use the Nonlinear airframe.

Linear Airframe

The linear state space model and trim input values are obtained by linearizing the nonlinear model using the trimLinearizeOpPoint function in linearAirframe folder in the project. The trimLinearizeOpPoint function uses the linearize (Simulink Control Design) function.

Set VSS_VEHICLE to 0 use the Linear airframe.