Agriculture Reference
In-Depth Information
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FIGURE 7.22
Geometric configurations of industrial robots. (a) Cartesian, (b) cylindrical,
(c) spherical, and (d) articulated.
In 1986, a new prototype (MAGALI) was built (Grand D'Esnon et al., 1987) that
used a spherical manipulator servoed by a camera set at the center of the rotation
axes. Figure 7.23 shows the spherical manipulator that can execute a pantographic
prismatic movement (only rotational joints) along with two rotations.
In 1986, the University of Florida, along with other collaborators, initiated a pro-
gram to develop a robotic system for citrus harvesting (Harrell et al., 1988). The
outcome of this research was a 3-DOF manipulator actuated with servo-hydraulic
drives. Joints 0 and 1 were revolute and Joint 2 was prismatic. This geometry was
characteristic of a spherical coordinate robot (Figure 7.24). The feasibility of a
robotic citrus harvester was ascertained by this research work.
The French-Spanish Eureka project (Rabatel et al., 1995), started in 1991, was
based on the feasibility study done at the University of Florida. The proposed
robotic system had a dual harvesting arm configuration to achieve greatest economic
returns. However, their prototype consisted of only one harvesting arm. The arm
had two modules, an elevating arm and a picking arm. The picking arm was of a
pantographic structure rather than a linear structure. The elevating arm supported
the picking arm and the associated camera. The elevating arm was equipped with a
lateral DOF to avoid collision of the picking arm with the vegetation, while acting as
a fruit conveyor as well.
A mandarin orange harvesting robot for the orchard named “Kubota” designed
in Japan in 1989 by Hayashi, Ueda, and Suzuki was reported by Sarig (1993) and
