Studies on the Computer Control Technic for Farm Tractor's Implement.

对于设计一台控制农用机械的计算机或在农用拖拉机上创造高效的工作，测量一个实际工作的农用拖拉机-机具系统的行为和条件是至关重要的。本研究开发了拖拉机行为超声多普勒雷达监测系统。拖拉机性能监测系统的控制部分由一片16KB的只读存储器、256字节的随机存储器、54个I/O口和32×256点的大屏幕液晶显示器构成。并可通过RS232C接口显示和输出车速、车轮打滑、油耗、8路模拟量和17路数字量等测量数据。超声波多普勒雷达系统测量的实际车速范围为5 cm/s~5 m/s，重复精度在标准误差下可达1 cm/s。在4℃或0℃等低温条件下，测量精度不到3%。用该系统测量拖拉机耕作时，驱动轮滑移率范围为0~80%，与田间条件密切相关，尤其与土壤硬度密切相关。实践证明，该系统可用于农用拖拉机作业状态的测量。

It is most important thing for designing a computer controlling farm machine or creating efficient work on farm tractor to measure the behavior and conditions of a real working farm tractor-implement system. In this study, the tractor behavior monitoring system used with ultra-sonic doppler radar was developed. And the data taken from several tractor works in the field are shown many advisable results, but as the data are widely spread it cannot point out that the advisable check point for operation or to create design standard.The control part of the tractor behavior monitoring system are constructed by one chip microcomputer which has 16kb ROM, 256byte RAM, 54 I/O port and 32x256 dots large LCD. And it can disply and output via RS232C port the measured data, such as speed, slip on wheel, fuel consumption, 8-analog data and 17 digital data.The ultra-sonic doppler radar system measures the real traveling speed from 5 cm/sec to 5 m/sec with repeatable accuracy up to 1 cm/sec on standard error. And in low temperature condition such as 4 or 0 centigrade, the accuracy of measurement was less than 3%.When the tractor plowing operations were measured by the developed system, the slip data of the drive wheel spread from 0 to 80%, and closely related to the field conditions, especially hardness of soil. It is confirmed that the system is useful to measure the farm tractor operation.