Self-walking variable-quantity liquid medicine spraying device and liquid medicine spraying method for grapery

The invention relates to the technical field of crop liquid medicine spraying, and discloses a self-walking variable-quantity liquid medicine spraying device and a liquid medicine spraying method for a grapery. The liquid medicine spraying device includes a walking machine body, as well as a hydraulic system, a liquid medicine box, a gate-type spray bar, a GPS receiver and a control system which are installed on the walking machine body respectively; locating information character strings of a satellite are sent by the GPS receiver to the control system through a serial port; collected position signals, speed signals and flow signals are respectively sent to the control system through a position sensor, a speed sensor and a flow sensor; and the received signals are converted to control signals by the control system, and the control signals are transmitted to the hydraulic system so as to control the steering and walking path of a steering mechanism. The self-walking variable-quantity liquid medicine spraying device and the liquid medicine spraying method provided by the invention have the advantages that unmanned self-walking variable-quantity liquid medicine spraying is realized, the automation degree of the liquid medicine device of the grapery is improved, the influence of manual factors is reduced, the uniformity and stability of spraying are excellent, night operation can be realized, and the walking trace going forward as per the set trace is guaranteed.