Fluid Power Systems
C. E. Goering,* R. S. Book, C. H. Chou
University of Illinois

In cooperation with Vickers, Inc., a computer simulation is being developed of a fluid power system used in heavily loaded cranes. A unique directional control valve developed by Vickers prevents actuator overrunning and pressure fluctuations normally caused by the inertia of heavy loads. The computer simulation can accelerate the normally lengthy design process. The simulation developed to date gives results that agree with many aspects of measured field performance. Additional development is needed, especially in modeling the load-sensing pump in the system.

Machine vision sensing has been developed as an information source for a variety of applications in agricultural vehicle guidance and control. Applications include vehicle guidance based on pathways defined by crops, rows, or artificial markets. In addition to vehicle guidance, machine vision sensing of characteristics of vegetation for sprayer control has been investigated.

A computer program has been developed and released which determines the optimum machinery set for a farm. With specification of the desired field operations and corresponding work hours and areas to be covered, the program schedules the operations and calculates the costs of different machinery sets. The least cost (optimum) machinery set is determined using an optimization procedure. Management details of the least cost set or other sets are provided.

A soil compaction study is underway to determine effects of wheel traffic on crop growth and yield. Treatments include no extra wheel traffic, extra wheel traffic on every other row, and wheel traffic over the entire plot area before planting. Crop yields have decreased due to soil compac- tion in some years, especially in years when drainage is inadequate.

Several tillage systems for crop production are being evaluated at Urbana and at the six University of Illinois Agricultural Research Stations. Tillage treatments vary from conventional moldboard plow or chisel plow to no-tillage with monocropping and crop rotations. Principal factors being studied are crop establishment, growth, and yield; soil condition and fertility; soil erosion; weed control; and economics.