CHAPTER 4
 DESIGN OF THE FLORIDA CITRUS-PICKING ROBOT


 An overview of the design of the orange-picking robot, developed by Harrell et al.

(1988), is presented in this chapter. The physical specifications of each part of the robot are

described in the first section along with the position and orientation of the kinematic

coordinate frames as they relate to each physical component. The second section contains a

description of the computer hardware and software designed to control the robot. In the third

section, an illustration of the picking mechanism is introduced showing the configuration of the

components of the fruit sensor package. Hydraulic actuation of the robot is described in the

fourth section of the chapter. Finally, sensing mechanisms for position and velocity of the robot

joints are described in the fifth and sixth sections.


 Mechanical Design

 A brief description of the physical components that make up the orange-picking robot

are presented in this section. The parts are described along with their relationship to one

another. Also, presented in this section are the axes about which the motion of the robot is

accomplished. These axes of rotation form the Z axes of three-dimensional kinematic frames

which will be presented in a later chapter. The position and orientation of the kinematic

frames as related to the physical components are presented here as an aid in understanding the

kinematics chapter which follows.

 The orange-picking robot (Figure 4.1) was built as four major parts: base stand, outer

link, inner link, and sliding tube. The base of the robot was bolted to the flat bed of the

laboratory trailer and acted as a stand to support the other components (Figure 4.2). The first

coordinate frame, frame 0, of the kinematic model was assigned to the base link as shown in the

figure. On the base, the outer link was supported by flange bearings which allowed the outer

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