Precision Agriculture, 1, 199᎐216 1999
ᮊ 1999 Kluwer Academic Publishers. Manufactured in The Netherlands.
Vision Guided Precision Cultivation
D. C. SLAUGHTER, P. CHEN AND R. G. CURLEY email@example.com
Biological and Agricultural Engineering, Uni
ersity of California, Da
is, California 95616
Abstract. A color machine vision based automatic guidance system was developed for precision
guidance of an agricultural cultivator. The guidance system was designed to operate in weedy row crop
fields at the time of first cultivation. The performance of the system varied from an RMS guidance error
of 7 mm under low weed loads to 12 mm under high weed loads and was capable of operating at travel
speeds up to 16 kmrh.
Keywords: cultivation, guidance, machine vision, robotics, weed control
Agricultural field equipment is still largely guided by manual means despite several
decades of effort to develop automatic guidance systems for agriculture Jahns,
1983; Tillett, 1991 . Despite the lack of adoption, the goal of mitigating the
drudgery of repetitive manual operation of field equipment is still venerable.
Automatic guidance also has the potential to increase productivity by eliminating
redundant or missed implement andror chemical coverage between two adjacent
passes Palmer and Matheson, 1988; Palmer, 1984 . Successful automatic guidance
could also alleviate the stress and tedium of row crop operations and enhance safe
and precise practices.
Chancellor 1981 studied the principle of substituting information for energy in
agriculture and observed that the efficiency of a technology depends upon its
ability to use information to guide and time the application of resources. Chancel-
lor cited examples where the operational processes were not changed but added
information was used to actuate control so that optimal energy savings were
possible. Chancellor observed in his ‘‘information-for-energy’’ study that micro-
computers offered opportunities for efficient handling and processing of more
management information than traditional manual methods and that these improve-
ments offered potential energy savings of about 15% in existing agricultural
operations. In this regard, if the exact location of each crop plant was known then
cultivation tools could be positioned to remove a higher percentage of the weeds
with a minimal increase in energy use. The added energy input to precisely position
these tools would be greatly offset by the reduction in manual labor required to
remove weeds by hand hoeing.
Kaminaka et al. 1981 studied the steering performance of a tractor operator as
the complexity of the task increased from steering only the tractor to steering the
tractor plus monitoring an implement located behind the tractor. They found that