Wt(Tp Tl)
We Tp
Field efficiency (5)
When We = effective working width m.
Wt = Theoretical working width m.
. .100
all amount of cassava on the test range
Conveying losses number of cassava retained on the ground (6)
3. RESULTS AND DISCUSSION
The functional test for the Cassava Digging and Preparing Unit and Conveyor Units in the
bed uses the agriculturalist’s method to plant and maintain the cassava. Testing in harvest
season (Oct.-Feb.) shows the following results:
3.1 Functional Result of Cassava Digging and Preparing Unit
The result of the functional test of Cassava Digging and Preparing Units (Table 1) shows
that there is still some rain in October. The average moisture content of soil is more than
25% (wb). The soil is soft but quite sticky. Therefore, the digger can’t separate cassava
rhizomes from soil after digging.
Table 1. Result of functional test for cassava digging and preparing unit with different
angles of digger in 5 levels of soil moisture
Month Moisture
(%wb)
Digging angle
(Degree)
Size of soil clods after
digging
The average
of draft
% of the force (N)
soil clods
bigger than
75 mm.
Average
size of the
soil clods
(mm.)