Abstract:
Abstract: Wireless remote control walking rice transplanter has broad market prospects and a high application value. Its 180° turning without manual assistance in the paddy field is a difficult problem. Based on the analysis of the operations of the walking transplanter in the paddy field, a kind of walking assist mechanism that can be lifted and descended was invented. Thanks to the substantial lifting and descending functions, the floating plate can be fully lifted away from the mud surface in the paddy field, and the resistance to turning can be reduced. A kinematics model was established for this mechanism on the basis of the analysis of the structural characteristics and working principles of this mechanism, while the multi-objective and multi-parameter optimized model was proposed for the walking assist mechanism according to its structural characteristics as well as operating requirements of wireless remote control walking rice transplanter in the paddy field. The computer-aided design and analysis software based on Visual Basic 6.0 was developed, and the "parameter-guided" heuristic optimization algorithm invented by the researcher team was embedded in this software for quick optimal solutions in order to get a group of parameters meeting the working requirements of the walking assist mechanism. Based on the optimized parameters, the structural design of the walking assist mechanism was carried out, and the trial physical prototype was manufactured. At the same time, C Language was applied to carry out the re-development of the microcontroller development board, which was used as signal transmission module for sending the control commands (remote control function). The minimum system of the single-chip microcomputer was used as the vehicle-based signal processing module. The end pneumatic actuator system was developed in order to convert the control commands into the actual actions of the rice transplanter and to realize the automatic operation. The signal processing module used the character variables to receive the commands from the storage signal transmission module. The cylinder numbers respectively correspond to the solenoid valves, the relays, and the single-chip microcomputer pins, so that the "on" and "off" of the cylinders with the corresponding number can be controlled according to the judgment results on the character variables. By this way, different cylinders' "on/off" acting as a group realized the actions of the rice transplanter. Finally, the physical prototype of the walking assist mechanism, signal processing module and end pneumatic actuator system were fitted to the walking transplanter, and the test was carried out in paddy field with the specifications of 10 m×20 m and the mud depth of 15-25 cm, and the walking speed of the transplanter was set as 0.45 m/s and 0.90m/s. The test results showed that, in the wireless remote control state, the machine successfully completed the operation of planting, straight driving, automatic 90° turning and 180° turning in the paddy field. The walking assist mechanism and control system meet the requirements of the field operation of the wireless remote control walking rice transplanter, that proves the feasibility of the mechanism and the control system.