PRUNING - A CRITICAL PERENNIAL OPERATION REQUIRED TO MAINTAIN TREE HEALTH AND PRODUCE HIGH YIELDS OF QUALITY FRUIT - IS ONE OF THE MOST LABOR-INTENSIVE ORCHARD ACTIVITIES IN THE PRODUCTION OF HIGH-VALUE TREE FRUIT CROPS. AS THE FRESH MARKET TREE FRUIT INDUSTRY CONTINUES TO FACE THE CHALLENGE OF AN UNCERTAIN LABOR FORCE, THE DEVELOPMENT OF ROBOTIC TECHNOLOGIES THAT ARE ABLE TO PERFORM LABOR-INTENSIVE FIELD OPERATIONS - LIKE PRUNING - WILL PLAY A CRUCIAL ROLE IN ITS LONG-TERM SUSTAINABILITY. AUTOMATING SELECTIVE PRUNING IS A COMPLEX PROBLEM REQUIRING HIGH-RESOLUTION SENSING, COMPLEX MANIPULATION, AND ADVANCED DECISION MAKING ON DETERMINING WHICH BRANCHES TO PRUNE. THE SPECIFIC RESEARCH OBJECTIVE OF THIS PROJECT IS TO DEVELOP A ROBOTIC SYSTEM FOR AUTONOMOUS, DORMANT PRUNING OF FRUIT TREES. TO ACCOMPLISH OUR OBJECTIVE, WE HAVE FORMED AN EXPERIENCED, INTERDISCIPLINARY PROJECT TEAM WITH EXPERTISE IN HORTICULTURE, AGRICULTURAL MECHANIZATION, COMPUTER GRAPHICS, AND ROBOTICS.OUR APPROACH BUILDS ON PRELIMINARY INVESTIGATIONS, WHICH INDICATE THAT MACHINE VISION SYSTEMS CAN BE USED TO ANALYZE THE MANUAL PRUNING PROCESS TO I) FORMULATE PRUNING RULES, AND II) IDENTIFY PRUNING LOCATIONS FOR AUTONOMOUS PRUNING OF FRUIT TREES. SPECIFICALLY, OUR APPROACH IS TO FIRST BUILD HIGH-QUALITY DIGITAL MODELS OF THE TREES OFFLINE USING A COMBINATION OF ARTIFICIAL INTELLIGENCE TECHNIQUES AND HUMAN INTERVENTION. SECOND, WE USE THE KNOWLEDGE GAINED FROM STUDYING THE MANUAL PRUNING PROCESS TO FORMULATE PRUNING RULES, WHICH CAN BE 'PRACTICED' ON THE DIGITAL MODELS AND EVALUATED FOR THEIR EFFECTIVENESS. THIRD, WE WILL USE STATE-OF-THE-ART MACHINE LEARNING ALGORITHMS TO MAP PRUNING PLANS BACK TO THE REAL WORLD IN ORDER TO REDUCE ONSITE COMPUTATIONAL DEMANDS. FOURTH, WE WILL DESIGN A CUSTOM END-EFFECTOR THAT CAN LOCALIZE ITSELF IN REAL TIME IN ORDER TO SAFELY AND RELIABLY PERFORM THE PRUNING CUTS. WE EXPECT THAT THE PROPOSED ROBOTIC PRUNING SYSTEM WILL HELP SUSTAIN THE GLOBAL COMPETITIVENESSOF THE US TREE FRUIT INDUSTRY. IN ADDITION, CONSUMERS WILL BENEFIT THROUGH INCREASED ACCESS TO PREMIUM QUALITY FRUIT.