A computer-controlled four-wheel drive 15.4 kW tractor was used in this study (Fig. 5.1).
The experimental tractor was modified for autonomous control using a Keyence KZ-A500
Programmable Logic Controller (PLC) and relay switches as its executive control
regulating hydraulic actuators based on data measured by sensors. The sensory data and
control status were transmitted to an upper level controller through parallel communication.
The basic instrumentation system for the autonomous tractor is depicted in Fig. 5.2.