Design and experiment of a GPS-based turn compensation system for improving the seeding uniformity of maize planter

Abstract The ability to compensate for seeding rates of planter units has the potential to mitigate the problem of inaccurate seed application rates due to lateral speed differences of planter units when planters are turning. This would result in an increase in crop yields and a reduction of the seed usage. In this article, a GPS-based turn compensation algorithm was designed to offset the seeding rates of planter units, and a simulation model in which the turning radius varied was built using MATLAB Simulink to evaluate the factors (the positioning accuracy, frequency of the GPS receiver, and travel speed) affecting the performance of the developed turn compensation system. Field experiments indicated that a four-row planter equipped with the developed turn compensation control system had better seeding accuracy (above 97%) and seeding coefficient of variation (below 1.52%) values than those of a non-compensation planter under equivalent working conditions, and a uniform seed spacing between planting rows could be obtained regardless of the change in the turning radius, indicating that the developed system could offset the seeding rates of every row automatically by turn compensation. The GPS used in this paper can be shared with a tractor automatic navigation system or any farm machinery equipped with a GPS device, which facilitates the manufacturing cost reduction and as well as the integration of this system and other agricultural machinery control modules.