DEVELOPMENT OF MECHANICAL APPARATUS
The mechanical apparatus was designed to achieve a production rate similar to the existing traditional hand scoop harvester to sustain the source of cockles in the country , thus protecting them from over-fishing or over-exploitation . Therefore , each harvesting process employed must be carried out under the permit of the State Fisheries Office with certain conditions such as the minimum allowed cockle size to be harvested and using allowed apparatus as stated in the related regulation .
Nowadays , fishermen use the existing hand scoop . The chosen design of the mechanical apparatus was based on the predicted time for the hand harvesting process i . e . 2 to 3 minutes for each effort . The initial material for the proposed prototype used was stainless steel with the average scoop weight of about three kilogrammes . The ergonomic study of the proposed mechanical apparatus prototype and the existing hand scoop was done at the natural cockle beds at Sanglang , Pontian , Johor . There were four different mechanical apparatus considered for the study : pulley and cable ( Figure 2 ), pulley and gear ( Figure 3 ), pulley and gear with steering ( Figure 4 ) and manipulated weight ( Figure 5 ).
Figure 2 : Pulley and cable
Figure 3 : Pulley and gear
Figure 4 : Pulley and gear with steering
ERGONOMIC STUDY
Two types of ergonomic evaluations were conducted in the study . They were muscle activity assessment and spine kinematic assessment .
Muscle activity assessment The assessment design was set up according to Mirka et al . ( 2011 ). For muscle activity evaluation , surface electromyography ( sEMG ) was used to evaluate and record the electrical activity produced by the muscles . The MegaWin 3.0 surface electromyography device , designed to support Mega Electronics ( ME6000 ) bio-signal measuring device was selected for this part of the study .
Three fishermen were voluntarily involved in the study . Five muscles on both sides of the participants ’ body were monitored while they were working . They were the muscles on both sides
Figure 5 : Manipulated weight
31