Field performance of proposed foresight tillage depth control system for rotary implements mounted on an agricultural tractor

Indoor experiments to evaluate the response characteristics of the proposed foresight tillage depth control system for rotary implements mounted on an agricultural tractor were done under various conditions and the result of experiments was reported in our previous paper [Lee J, Yamazaki M, Oida A, Nakashima H, Shimizu H. Electro-hydraulic tillage depth control system for rotary implements mounted on agricultural tractor-design and response experiments of a control system, Journal of Terramechanics 1998;35(4):229-238]. Then, the experiments were conducted in an actual field to evaluate the adaptability of the control system to a field. The transient response experiment, by giving the step variation in the set tillage depth through a computer keyboard and the response to the pitching experiment: by giving the compulsory step variation in the pitching angle to the tractor by a pit, which was dug in the experimental field, were conducted under two steps of tractor running speeds, two kinds of sampling frequencies and so on. Besides of the proposed foresight control system, a non-foresight control system and a no-control system were also tried to be served in the field. The result of the field experiments for these control systems will be discussed in this paper. (C) 2000 ISTVS. All rights reserved.