hydraulically actuated manipulator was mounted on the rear, flatbed portion of the lab. A 15

kW electric generator furnished electricity for the hydraulic power unit, the control computer,

and other hardware used in the development of software for the grove model robot. Visual

access to the robot was furnished by three windows mounted on the rear and picking side of the

control room.

 The robot was a three degree-of-freedom, spherical-coordinate geometry arm.

Actuation of the joints was accomplished through the use of servo-hydraulic drives consisting

of servo amplifiers, servo valves, and actuators. For the first two joints, rotary actuators were

used to generate the revolute motion about intersecting horizontal and vertical axes. The third

joint, a sliding joint, was actuated by a hydraulic motor through a rack and pinion drive. The

revolute motion of the first two joints provided the robot with the ability to point toward a

fruit, and the prismatic or sliding joint provided the ability to reach toward the targeted fruit.

A picking mechanism was attached to the end of the arm and enclosed the color CCD camera

and ultrasonic ranging transducer which were used for fruit detection. Also, a rotating lip was

attached to the picking mechanism which was used to grasp the fruit and remove it from the

tree. The motion of the joints was determined by an intelligence base which used the

information from the position and velocity sensors on the joints as well as the fruit sensors to

establish desired actions of the manipulator.

 The intelligence for the robot was built around a concept of states or modes of operation

in which decisions were made based on the available information from the sensors. The

intelligence base was developed and programmed for the orange-picking robot by Adsit (1989).

The heart of the intelligence base was a state network which provided robot command

decisions through sensing, action, and reasoning agents. Sensing agents were used to quantify

the robot's work environment and the robot's status. Reasoning agents made decisions in regard

to the information from the sensing agents. Action agents caused motion of the robot to alter the

work environment or the sensor's perception of the work environment. These agents were linked

together by a common database with result fields, parameter fields, and activate fields. The