Abstract:

According to the investigation of the imaging model for central omnidirectional cameras, a new measurment method for rotor pyramid angle is proposed. The omnidirectional camera installed on the hub of helicopter rotates with the rotor to take the picture of the planar grids pasting on the rotor blade. According to the grid corners coordinates and their associated image values, a method for calculating the planar grid’s extrinsic parameters is given, and a group of equations are also given to calculate the helicopter blade pyramid angle. There is no special requirements for the installing of the omnidirectional camera on the hub of helicopter. By changing the position of the planar grids, the pyramid angle on arbitrary position of the rotor blade can be calculated. So it is a flexibility approach compared with existing measuring methods. Experimental results show that the error of this method is within ±5 mm.