Abstract
The objective of this research was to develop a sub-measurement unit that integrates the serial data from a GPS device and signals from various sensors triggered by the GPS signal. Since the unit uses a commercially available microcomputer, it can easily be used to build inexpensive measurement systems consisting of a data-logging unit, the sub-measurement unit, a GPS device, and various sensors whose output signals are analog or pulse signals. The sub-measurement unit can be used to integrate signals by simply connecting the GPS device and sensors.
This report discusses, as examples of application of the unit, systems for measuring yield and slip ratio. Results of field experiments showed that these systems could be used for acquiring combine harvesting data and rotary tillage data.
The sub-measurement unit is not limited to systems measuring yield and slip ratio or by the requirement that the sensor signals be either analog or pulse signals. It can therefore be used to set up systems that gather various kinds of data (concerning, e. g., crop growth, machine operation, labor intensity, and the working environment) and integrate this data with positional information. A wireless modem for data logging can also be incorporated into the unit.
