hand harvesting of beans, the crop is first cut and then for drying it is left on the field for a few days. Next to thresh it and separate the kernels from stalks it will be transferred to the stack. In order to develop mechanization and reduce harvesting costs a bean harvesting machine is necessary. In this research a bean gathering head was designed and fabricated. Because of high flexibility and low cost, active stalk remover with chain conveyor was used to lift bushes from the ground. Elastic fingers used on holding shaft penetrate into the lying crop and carry it. A cam path was used to create a suitable position for fingers and provide gentle exit from weaved bushes. This path causes fingers to touch sprocket and exit from bushes with minimum elongation. The machine was connected to tractor by means of a single hitch point system. A hydraulic motor was used to drive the machine. The required power was calculated 1.5 hp at 47.8 rpm of the sprocket. A pneumatic collector was designed to gather pods, kernels and leaves left on the ground as a result or shatter caused by impact forces on the beans bushes during mechanical harvest. To separate additional materials such as gravels and dust a cyclone was designed which its basic cylinder and cone height dimensions was calculated based on aerodynamic properties of the crop and JCS cyclones standard. The required fan power was calculated to be 2.45 hp with an efficiency of % 70. In this research the tests were conducted to determine terminal velocity, drag coefficient and static frictional coefficient for Fars pinto bean. Aerodynamic tests took in flotation method at three size group and nine replications. Frictional properties tests were conducted on inclined surface covered with glass, plexiglas, wood and galvanized plate surfaces. All the tests were at three moisture content (MC) levels of 8, 12 and % 16 on a wet basis. The mean value of terminal velocity was 13.79 m/s and the drag coefficient was 0.739. According to statistical analysis results, MC had a significant effect on the measured aerodynamic properties at % 5 significant level. The results showed that the terminal velocity value first increased and then decreased as the MC increased and the drag coefficient first decreased and then increased as MC increased. Among all the frictional surfaces the galvanized plate had the maximum static frictional coefficient (0.44). The results of statistical analysis for frictional coefficient indicated that MC and surface type had a significant effect at % 1 significant level. The results showed that the static frictional coefficient increased as MC increased.
