well as the limited potential market Glancey, J.L., W.E. Kee, T.L. Wootten, for specialty harvesters for these minor and D.W. Hofstetter. 1998. Feasibility of Engineering and crops. once-over mechanical harvest of processing Horticultural Clear interactions exist between squash. ASAE Paper No. 98-1093. Amer. the cultivar, cultural practices, a Soc. Agr. Eng., St. Joseph, Mich. Aspects of Robotic mechanical harvester and several Glancey, J.L., W.E. Kee, T.L. Wootten, postharvest requirements. As a result, M.D. Dukes, and B.C. Postles. 1996. Field Fruit Harvesting: a system-level approach is critical losses for mechanically harvested green peas for developing economically viable, for processing. J. Veg. Crop Production Opportunities and highly automated vegetable produc- 2(1):61–81. tion systems. Furthermore, improve- Kahn, B.A., Y. Wu, N.O. Maness, J.B. Constraints ments in plant architectures and yields Solie, and R.W. Whitney. 2003. Densely planted okra for destructive harvest: III. and other modifi cations to crops are 1 2 required before some vegetables can Effects of nitrogen nutrition. HortScience T. Burks , F. Villegas , be machine harvested. Some of the 38(7):1370–1373. M. Hannan3, S. Flood3, attributes requiring further develop- Inman, J.W. 2003. Fresh vegetable harvest- 3 ment include, but are not limited to, ing. Resource: Engineering and Technol- B. Sivaraman , better fruit location within the plant ogy for Sustainable World 10(8):7–8. V. Subramanian3, and J.Sikes3 structure, more uniform fruit sets, in- Palau, E. and A . Torregrosa. 1997. Me- creased mechanical damage resistance, chanical harvesting of paprika peppers in prevention of premature or diffi cult Spain. J. Agr. Eng. Res. 66(3):195–201. ADDITIONAL INDEX WORDS. selective fruit detachment, and more robust harvesting, automated production, postharvest quality and stability. Roberson, G.T. 2000. Precision agriculture machine vision The integration of new tech- technology for horticultural crop produc- tion. HortTechnology 10(3):448–451. SUMMARY. Automated solutions for nologies including DGPS, automatic fresh market fruit and vegetable machine guidance, and computer- Upadhyaya, S.K., U. Rosa, M. Ehsani, M. harvesting have been studied by based vision systems offers signifi cant Koller, M. Josiah, and T. Shikanai. 1999. numerous researchers around the performance benefi ts, and is a substan- Precision farming in a tomato production world during the past several decades. tial component of current vegetable system. ASAE Paper No. 99-1147. Amer. However, very few developments have production and harvesting research in Soc. Agr. Eng., St. Joseph, Mich. been adopted and put into practice. The reasons for this lack of success are the U.S. As costs continue to decrease U.S Dept. Agr. 2004. Vegetables at a due to technical, economic, horti- for these new technologies, commercial glance: Area, production, value, unit value, cultural, and producer acceptance trade and per capita use. 25 June 2004. adoption will increase. issues. The solutions to agricultural <http://www.ers.usda.gov/briefi ng/veg- robotic mechanization problems are etables/vegpdf/VetAtAGlance.pdf>. Literature cited multidisciplinary in nature. Although Arndt, G., W.M. Perry, and R. Rudziejew- Vassallo, M., E. Benson, and W.E. Kee. there have been signifi cant technol- ski. 1994. Advances in robotized asparagus 2002. Evaluation of multispectral im- ogy advances during the past decade, harvesting, p. 261–266. Proc. 25th Intl. ages for harvester guidance. ASAE Paper many scientifi c challenges remain. Symp. Industrial Robots. No. 02-1202. Amer. Soc. Agr. Eng., St. Viable solutions will require engi- Joseph, Mich. neers and horticultural scientists who Arndt, G., R., R. Rudziejewski, and understand crop-specifi c biological V.A. Stewart. 1997. On the future of Wall, M.W., S. Walker, A. Wall, E. Hugh- systems and production practices, automated selective asparagus harvesting sand, and R. Phillips. 2003. Yield and qual- as well as the machinery, robotics, technology. Computers Electronics Agr. ity of machine-harvested red chile peppers. and controls issues associated with 16(2):137–145. HortTechnology 13(2):296–302. the automated production systems. Focused multidisciplinary teams are Cho, S.I., K.J. An, Y.Y. Kim, and S.J.Chang. Wu. Y, B.A. Kahn, N.O. Maness, J.B. needed to address the full range of 2002. Development of a three-degrees-of- Solie, R.W. Whitney, and K.E. Conway. commodity-specifi c technical issues freedom robot for harvesting lettuce using 2003a. Densely planted okra for destructive involved. Although there will be com- machine vision and fuzzy logic control. harvest: II. Effects on plant architecture. mon technology components, such Biosystems Eng. 82(2):143–149. HortScience 38(7):1365–1369. as machine vision, robotic manipula- Glancey, J.L. 2003. Machine design for veg- Wu. Y, B.A. Kahn, N.O. Maness, J.B. etable production systems, p. 1105–1115. Solie, R.W. Whitney, and K.E. Conway. 1PhD, PE, Assistant Professor, University of Florida, In: D.R. Heldman (ed.). The encyclopedia 2003b. Densely planted okra for destructive 225 Frazier-Rogers Hall, PO Box 110570, Gainesville, of agricultural, food and biological engi- harvest: I. Effects on yield. HortScience FL 32611-0570. To whom reprint requests should be addressed. E-mail: [email protected]fl .edu neering. Marcel Dekker, New York. 38(7):1360–1364. 2Postdoctorate, University of Florida, Agricultural and Glancey, J.L., W.E. Kee, T.L. Wootten, Biological Engineering Department, Gainesville. and M.D. Dukes. 2004. Effects of plant 3PhD Candidate, University of Florida, Agricultural and architecture on the mechanical recovery Biological Engineering Department, Gainesville. of bush-type vegetable crops. ASAE Paper Acknowledgments. Research conducted at the Uni- No. 041024. Amer. Soc. Agr. Eng., St. versity of Florida, Institute of Food and Agricultural Joseph, Mich. Sciences, through funding provided by the Florida Department of Citrus. Special thanks are given to M. Wilder for her help in editing this manuscript. This is a Florida Agricultural Experiment Station Journal Series R-09821. ● January–March 2005 15(1) 79 JJan2005HT.indban2005HT.indb 7799 112/6/042/6/04 44:35:15:35:15 PPMM WORKSHOP tion, vehicle guidance, and so on, each of robotic mechanization for horticul- crops requires major design compo- application will be specialized, due to tural crop harvesting systems. In order nents—machine, variety, and cultural the unique nature of the biological to provide the reader with suffi cient practices. A systems development ap- system. Collaboration and technology breadth of information, this paper is proach must be followed to insure that sharing between commodity groups primarily a literature survey and syn- all three aspects are considered (Sims, offers the benefi t of leveraged research and development dollars and reduced thesis, which tries to identify the key 1969). The major aspects related to overall development time for multiple issues that robotic system developers cultural practices that affect fruit and commodities. This paper presents an and horticultural scientists should vegetable mechanical harvesting in- overview of the major horticultural consider to optimize plant–machine clude fi eld conditions, plant population and engineering aspects of robotic system performance. and spacing, and plant shape and size. mechanization for horticultural crop Effi cient harvest mechanization cannot harvesting systems. Horticultural aspects of be achieved by machine design alone. robotic harvesting Establishing favorable fi eld conditions Robotic solutions for fresh market for the harvesting system under devel- everal horticultural commodity fruit and vegetable harvesting have opment has to be considered before groups around the nation are been studied by numerous research- the harvesting system can be effectively Sfacing growing global market ers around the world during the past developed (Wolf and Alper, 1983). pressures that threaten their long- several decades. However, very few Peterson et al. (1999) developed term viability. For instance, Brazilian developments have been adopted and a robotic bulk harvesting system for orange (Citrus sinensis) growers can put into practice. The reasons for this apples. They trained the apple trees produce, process, and ship juice to lack of success are due to technical, using a Y-trellis system and found them Florida markets cheaper than can economic, horticultural, and pro- to be compatible with the mechanical Florida growers. In the event that tariffs ducer acceptance issues. In industrial robotic harvesting. Fruit was trained to are eliminated, numerous horticultural automation applications, the robots’ grow on the side and lower branches to commodities across the nation will not environment is designed for optimal improve fruit detection and removal. be able to compete in either domestic performance, eliminating as many They further suggested that pruning or international markets with their variables as possible through careful could enhance the harvesting process counterparts in Latin America and systems planning. In agricultural set- by removing unproductive branches Asia. The combination of low com- tings, environmental and horticultural that block effective harvesting. Further modity prices both domestically and control can be a signifi cant hurdle to research was suggested to determine abroad, high labor prices, and low successful automation. Not only must the variety and rootstock combinations labor productivity