Lift drag
LRAUV control surfaces:
| Property | Description | Value |
|---|---|---|
| area | Surface area of the link. | 122 cm^2 for one fin. |
| a0 | The initial "alpha" or initial angle of attack. a0 is also the y-intercept of the alpha-lift coefficient curve. | 0.0 degrees |
| cla | The ratio of the coefficient of lift and alpha slope before stall. Slope of the first portion of the alpha-lift coefficient curve. | C_{L\alpha} = 4.13 (alpha in radians) |
| cda | The ratio of the coefficient of drag and alpha slope before stall. The coefficient of drag at alpha =0 is 0.03. The ratio drag/aoa is given below. Please see Coeffs.png. | C_{D\alpha} = .04/.2 = .2 (alpha in radians) |
| cp | Center of pressure. The forces due to lift and drag will be applied here. | (3.7, 7.9) cm as shown in the attached diagram OriginalFin.png. This moves as a function of aoa, as show by the attached diagram cp.png. Note that cp.png is referenced to mean chord length, not the root chord length. |
| forward | 3-vector representing the forward direction of motion in the link frame. | [1 0 0] |
| upward | 3-vector representing the direction of lift or drag. | [0 0 -1] |
| alpha_stall | Angle of attack at stall point; the peak angle of attack. | 9.5 degrees (.17 rad) |
| cla_stall | The ratio of coefficient of lift and alpha slope after stall. Slope of the second portion of the alpha-lift coefficient curve. | -1.1 (alpha in radians) |
| cda_stall | The ratio of coefficient of drag and alpha slope after stall. | .030 (alpha in radians) |
Refer to Gazebo: Tutorial: Aerodynamics