Crop growth sensing apparatus and method supporting agricultural machinery variable-quantity fertilization operations

A crop growth multispectral sensor self-balancing apparatus, comprising a simple pendulum gear damping system, a simple pendulum non-circular gear damping system, a simple pendulum gear driving system, and a control assembly, wherein the crop growth sensor self-balancing apparatus is mounted on an agricultural machinery frame by means of a fastening plate;

• a first gear;
• a second gear, a third gear, and a fourth gear form the simple pendulum gear damping system;
• a first non-circular gear and a second non-circular gear form the simple pendulum non-circular gear damping system, wherein the simple pendulum gear damping system and the simple pendulum non-circular gear damping system are configured to inhibit an impact of a tilt of an agricultural machinery;
• the simple pendulum gear damping system constituted by the first gear, the second gear, the third gear, and the fourth gear is mounted on a frame;
• the third gear and the fourth gear are mounted on the fastening plate by means of a third shaft pin with a third bearing, and the first non-circular gear and the second non-circular gear are mounted on the frame respectively by means of a first shaft pin with a first bearing and a second shaft pin with a second bearing;
• a crop growth multispectral sensor is mounted on a position-adjustable plate;
• a gyroscope detects attitude information of the crop growth multispectral sensor, and applies, according to a predetermined target, a target control signal to a simple pendulum gear pair and the simple pendulum gear driving system constituted by a first brushless motor driver, a second brushless motor driver, and a third brushless motor driver;
• the target control signal implements a closed-loop control on the crop growth multispectral sensor in a balanced and steady state by using a PID control strategy based on an excitation-response model;
• and the control assembly comprises a processor and the gyroscope;
• wherein the gyroscope detects attitude information of the crop growth sensor, and the processor controls, according to the attitude information of the crop growth multispectral sensor;
• an assembly of the first brushless motor driver;
• the second brushless motor driver and the third brushless motor driver to controls the simple pendulum gear driving system to drive the agricultural machinery frame to perform an attitude adjustment on the crop growth multispectral sensor, to ensure that a angle between the crop growth multispectral sensor and a monitored crop is always kept within a range.

A crop growth sensing method supporting agricultural machinery variable-quantity fertilization operations, comprising the following steps:

• performing a vibration finite element analysis on a crop growth sensor shock-absorbing frame by using ANSYS software;
• during analysis, applying vibration models of an agricultural machinery, comprising an engine vibration model of the agricultural machinery and a vibration model for vehicle wheels and a farmland road surface, to a model as excitation inputs;
• respectively analyzing vibration amounts of crop growth sensors mounted at different positions of a cantilever beam, to obtain vibration amplitudes of the different positions;
• obtaining a union set of mounting positions satisfying the following two conditions:
• [1] H=Hs±Hv and HL≤H≤HH, wherein in a vibration condition, H is a distance between a crop growth multispectral sensor and a crop;
• Hs is a mounting height of the crop growth multispectral sensor;
• Hv is a vibration amplitude;
• HL is a lowest monitoring height of the crop growth multispectral sensor;
• and HH is a highest monitoring height of the crop growth multispectral sensor;
• and
• [2] R≤L≤1.5R, wherein R is a diameter of the field of view of the crop growth multispectral sensor;
• and L is a mounting distance of the crop growth multispectral sensor.