Paper Title
Front Attach Combine Harvesting Unit Implement With A Small Tractor For Upland Paddy Field

Abstract
This study aims to design and to develop the prototype of the front attach combine harvester install with small tractor for upland paddy field. After fabrication, the prototype was tested to evaluate the performance of 2 main components which include 1) the Reel and Cutter bar unit and 2) the threshing unit. The threshing unit composed of the spike-tooth cylinder diameter of 44 centimeters length of 130 centimeters, gap between cylinder and concave was about 20 millimeters. The speed of threshing drum was altered by power take off (PTO) shaft of tractor. In the experiment, the speed of threshing drum was varied at 3 different levels by adjusting PTO shaft speed of 300, 400 and 450 revolutions per minute. The evaluation of working efficiency was defined by 4 efficiency indexes which include 1) threshing efficiency 2) percentage of grain materials 3) percentage of grain losses and 4) percentage of un-grain materials.The Reel and Cutter bar unit was designed to harvest with the swathe width of 140 centimeters for 4 rows harvesting. The experiments were set up to investigate the optimal speed of cutter bar mechanism which confine by 2 parameters, included 1) the forward speed of tractor (varied at 0.9 and 1.1 kilometer per hour) and 2) the speed of cutter bar mechanism (varied at 3 levels by adjusting the PTO shaft of 300, 400 and 450 revolutions per minute). The results shown that the forward speed of 0.9 kilometer per hour and PTO shaft speed of 450 revolutions per minute. These speeds present the maximum value of cutting efficiency about 99.75%. The PTO speed of 450 revolutions per minute presented the maximum value of threshing efficiency, percentage of grain materials and minimum value of percentage of un-grain materials about 90.12, 96.80 and 9.69%, respectively. However, the PTO speed of 300 revolutions per minute presented the minimum value of percentage of grain-lose. Finally, when considered overall efficiency indexes, the machine performance (MP) was 59.72, 63.44 and 68.75% at the PTO speed of 300, 400, and 450 revolutions per minute, respectively. Index Termsó Combine Harvester, Upland rice, Attached to the tractor.