Question

1) A quadrotor flies by applying four thrust vectors [T1,T2,T3,T4] to achieve total force f and moments [Mx,My,Mz]. Assume all four quadrotor propellers lie in a common plane, each motor’s thrust acts perpendicular to the propeller disk, and that adjacent quadrotor motor shafts are separated as shown in the below figure. Assume the axis system defined in the below figure for all parts of this question, and that the center of gravity of the quadrotor is at the body midpoint ((xb,yb) = (0,0)) equidistant from all thrusters.

Suppose a quadrotor with mass m = 5kg has coefficient of thrust CT = 1.4E −5 and coefficient of moment CM = 3E −6. Note that the CT and CM coefficients have units of kg ·m and kg ·m2, respectively, given motor speeds ωi in rad/sec.

a) What four motor speeds ωi are required for the quadrotor to hover?

b) Suppose the quadrotor experiences a drag force D = c_DQV linear in horizontal speed V with quadrotor coefficient of drag c_DQ = 0.1kg/s. What pitch angle θ will allow the quadrotor to fly forward in steady flight at 5m/s?

Top View +x (forward) 01 02 T2 004 +y (right) 03 2d = 1.0 m

~~~ This quadrotor is in X-Configuration

Answer 1

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Total tovq4e about 91ver LF(22 LK (c LK (w.2w)