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In this paper, small-scaled blade prototypes with the flap-driving mechanism, called SNUF (Seoul National University Flap), were manufactured, and tested in order to realize vibratory load reduction in the rotor system. It was achieved by an active trailing-edge flap which is based on piezoelectric actuator. However, it turned out that the target value of the flap deflection angle was not accomplished in the previous designs. Therefore, the flap driving mechanism needs to be amended. Thus, a new piezoelectric actuator was selected to achieve the target deflection by considering the nonlinear relationship between flap deflection angle and the moment arm length. Re-selection of the actuator required increase of the blade inner space and its size. Therefore, it was required to validate the cross-sectional design of the improved blade configuration. So as to verify the structural integrity, crosssectional analysis was conducted by using UM/VABS. After achieving a satisfactory result of the non-rotating static test of the new flap-driving mechanism, a prototype blade will be manufactured and tested in the whirl tower.

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Motivated by the increasing demands on the precision of 3D large-scale measurement, the extrinsic parameters calibration with high accuracy of the bistatic non-orthogonal shafting laser theodolite (N-theodolite) system is required. A two-step method is proposed to achieve the extrinsic parameters calibration with high accuracy in this paper. In the first step, by analyzing and setting the approximate emitted point during the motion of the laser axis in local space, the calculation of the initial extrinsic parameters can be simplified. In the second step, the above results are taken as the initial values of optimization, and the distances between the spatial laser points provided by PSD sensors with high accuracy in global space are used to construct the unconstrained optimal objective function. The proposed method is validated with the measurement experiment of the bistatic N-theodolite system, the average error of 3D coordinate measurement is less than 0.4 mm, and the average error of distance measurement is less than 0.3 mm within 5 m.

The articulated laser sensor is a new kind of trans-scale and non-contact measurement instrument in regular-size space and industrial applications. These sensors overcome many deficiencies and application limitations of traditional measurement methods. The articulated laser sensor consists of two articulated laser sensing modules, and each module is made up of two rotary tables and one collimated laser. The three axes represent a non-orthogonal shaft architecture. The calibration method of system parameters for traditional instruments is no longer suitable. A novel high-accuracy calibration method of an articulated laser sensor for trans-scale 3D measurement is proposed. Based on perspective projection models and image processing techniques, the calibration method of the laser beam is the key innovative aspect of this study and is introduced in detail. The experimental results show that a maximum distance error of 0.05 mm was detected with the articulated laser sensor. We demonstrate that the proposed high-accuracy calibration method is feasible and effective, particularly for the calibration of laser beams.