The invention relates to an intelligent machine-carried mu measuring instrument, which belongs to the technical field of digital signal processing, and is mainly used for automatic detection on parameters such as arbitrary parcel area and man-hour price in the practical operation of a remote control pesticide spraying plane. A realization method comprises the following steps that 1, during unmanned plane operation, the GPS (global positioning system) point information of a parcel path is obtained every 3 to 5s, and is sent to an arbitrary parcel area automatic detecting system of a main control computer through a wireless module; 2, in the detecting system, boundary points are obtained through path discrete coordinate points by a triangular boundary estimating algorithm, and a boundary curve is obtained by utilizing a cubic spline function; 3, the defined area of the boundary curve is calculated by Matlab, and the parameters such as the parcel outline drawing, the area and the price are displayed on a GUI (graphical user interface); 4, finally, the parameters can be sent to an unmanned plane through the wireless module. The intelligent machine-carried mu measuring instrument aims at solving the problems that the traditional mu measuring instrument needs to operate along the boundary of land to be tested, the operation is contradictory with the practical operating operation of the unmanned plane, and the inherent defects such as poor measurement rate and low efficiency since the traditional irregular area adopts straight line fitting are overcome.