SHRINIVASA K. UPADHYAYA, Professor

PhD (Cornell University)
Department of Biological and Agricultural Engineering
3036 Bainer Hall
Tel (530) 752-8770
Email: skupadhyaya@ucdavis.edu
Web: http://faculty.engineering.ucdavis.edu/upadhyaya/index.html

Current Research

Professor Upadhyaya focuses the majority of his research in the precision farming area. His current interest is in developments of sensors and monitors for use in precision farming, traction and soil compaction, tillage, and field machinery design.

Applicability of the concept of precision agriculture or site-specific crop management (SSCM) in vegetable production is being pursued. Work is in progress on soil mineral-N and texture/soil compaction sensors. Soil mineral-N sensor is based on soil reflectance in the mid infrared region. A soil compaction profile sensor has been developed which can determine the variation in soil compactness to a depth of 0.6 m in increments of 7.5 cm. Yield monitors are being developed for vegetable and orchard crops. A continuous weigh type tomato yield monitor has been successfully developed. An electronic weigh bucket type yield monitor is being developed for pistachios and other orchard crops.

A multi-year research has been conducted to determine the relationship between tomato yield and soil and plant characteristics. The preliminary analysis indicates that nonuniformity in soil moisture distribution is the key factor influencing yield variability. The nonuniformity in soil moisture distribution is related to spatial variability in infiltrate rates, which in turn is influenced by soil compaction level. Field tests have been conducted to determine spatial variability in infiltration rates and relate it to variability in soil compaction level. Additional analysis of field data are being conducted to develop a decision support system for site-specific management of nutrient and water.

RTK GPS based planter has been developed to map seeds as they are planted and derive plant maps for subsequent weed control purposes. Tests are also being conducted to determine the advantages of RTK GPS based autoguidance system in irrigated agriculture. Preliminary results indicate that these systems can cultivate weeds very close to the plant at relatively high speeds and allow for drip tapes to be buried in the beds year after year.

Soil dynamics research is mainly concentrated on investigating the feasibility of using UC Davis traction prediction equations to control a tractor to optimize its performance in real-time.

Representative Recent Publications

Pelletier, M., and Upadhyaya, S. K. 1999. Development of a tomato yield monitor. Computers and Electronics in Agriculture 23:103-117.

Rosa, U. A., S. K. Upadhyaya, and P. Chen. 2000. Modeling and verification of an auto-FWD system. Transactions of the ASAE (American Society of Agricultural Engineers) 43(1):23-29.

Ehsani, M. R., M. Mattson, and S. K. Upadhyaya. 2000. An ultra-precise, GPS based planter for site-specific cultivation and plant specific chemical application. American Society of Agricultural Engineers Paper No. 00-3065.

Rosa, U. A., S. K. Upadhyaya, M. Josiah, M. Koller, M. Mattson, and M. G. Pelletier. 2000. Analysis of a tomato yield monitor. Transactions of the ASAE (American Society of Agricultural Engineers) 43(6):1331-1339.

Andrade, P., U. A. Rosa, S. K. Upadhyaya, B. M. Jenkins, U. A. Rosa, J. Aguera, and M. Josiah. 2001. Soil profile force measurements using an instrumented tine. American Society of Agricultural Engineers Paper No. 01-1060.

Upadhyaya, S. K., K. P. Lancas, A. G. Santo-Filho, and N. S. Raghuwanshi. 2001. One-pass tillage equipment outstrips conventional tillage method. California Agriculture 55(5):44-47.

Ehsani, M. R., S. K. Upadhyaya, W. R. Fawcett, L. V. Protsatilo, and D. Slaughter. 2001. Quantative measurement of soil nitrate content using mid-infrared diffuse reflectance spectroscopy. Transactions of the ASAE (American Society of Agricultural Engineers) 44(6):1931-1940.

Upadhyaya, S. K., U. A. Rosa, and D. Wulfshon. 2002. Application of finite element method in agricultural soil mechanics. Chapter 2, Advances in Soil Dynamics, Volume II. Edited by Upadhyaya et al., American Society of Agricultural Engineers Monograph, St. Joseph, MI. (In Press).

Upadhyaya, S. K., W. J. Chancellor, J. V. Perumpral, R. L. Schafer, W. R. Gill, and G. E. VandenBerg (Editors). 2002. Advances in Soil Dynamics, Vol. II. American Society of Agricultural Engineers Monograph, ASAE, St. Joseph, MI. 294 pp. (In Press).

Membership in Professional Societies

American Society of Agricultural Engineers
International Soil and Tillage Research Organization
International Society for Terrain Vehicle Systems

Courses Offered

EBS 130 - Dynamic Modeling of Processes in Biological Systems
EBS 215 - Soil-Machine Relations in Tillage and Traction
EBS 265 - Design and Analysis of Engineering Experiments
EBS 270 - Modeling and Analysis of Physical and Biological Process
ABT 175 - Introduction to Precision Agriculture

Research Support

California Energy Commission
California Tomato Research Institute
Trimble Navigation
Digital Media Innovation
United States Department of Agriculture
United States / Israel BARD