Automated calibration of a tractor transmission control unit

This paper presents an approach for an automated calibration process for electronic control units (ECU) of power split transmissions in agricultural tractors. Today the calibration process is done manually on a prototype tractor by experts. In order to reduce development costs the calibration process is shifted from prototype testing to software modelling. Simultaneous optimization methods are used within the software modelling to calculate new parameters. The simultaneous optimization includes objective evaluation methods to evaluate the tractor behaviour. With the combination of both methods inside the software modelling, the calibration process can be automated. The success of this approach depends on the quality of the software modelling. Therefore the identification of the initial prototype behaviour and the fitting of the tractor software model is done at the beginning. At the end of the automated calibration the validation and fine-tuning of the calculated parameters are done on the real tractor. These steps are condensed to a five step automated calibration process which includes simultaneous optimization and objective evaluation methods in several applications. After the detailed discussion of this automated calibration process one function of the ECU (one transmission component) will be calibrated through this process as example