Automatic working depth control for seed drill using ISO 11783 compatible tractor

The reliability of field work documentation and the functionality of PA systems set critical requirements for the instrumentation of agricultural implements. Precision agricultural machinery should be easy to use and operated without the need for automatic online controls that are map-based. The aim of the study was to develop automatic depth control system for a drill using an ISOBUS compatible tractor. In this paper, the instrumentation, the depth control model, and the control system of a prototype combine drill is described. A preliminary survey was carried out to choose sensors for the instrumentation of working depth control in a Junkkari Maestro 3000 combine drill. In the first phase of the research, a reliable measurement system based on multiple sensors was developed. A working depth model was then developed for the control of seeding depth. The control commands to hydraulic valves were transmitted using ISO 11783 network. In the second phase, all the sensors were calibrated indoors on a concrete floor. Field trials and measurements were carried out in during the final phase. For validating the theoretical model, the real depth of seeds was obtained from the soil profile by slicing after the germination of seeds. In the field tests automatic working depth control achieved accuracy of ±8 mm.