Abstract

                                Performance evaluation of an automatic gripping type transplanting mechanism for plug type vegetable seedlings was tested. Forty and twenty-five days old chilli, brinjal and tomato seedlings were used for the study. Well decomposed coco-pith (68.46 % moisture) was used as the medium for raising the seedlings. The tray contained 98 cells arranged in the order of 14 x 7. The growth characteristics of seedlings were recorded. A pneumatic actuated gripper for grasping and releasing the plug type seedling, pneumatic cylinder to remove the seedling from the protray cell and a linear rail used for transplanting the seedlings that moves on a linear guide way were the components of the automated system. The entire operations of transplanting mechanism were programmed in a microcontroller programmed with C++ software further controlled by Programmable Logic Controller (PLC) unit. Pneumatic air was supplied from compressor to the pneumatic actuated gripper and cylinder through Filter Regulator Lubricator (FRL) unit. The transplanting rate of developed mechanism was set as 20 – 25 seedlings / minute. The success ratios of automatic transplanting of seedlings were 87.22, 91.72 and 89.85, for 25 days old tomato seedlings, 40 days old chilli and brinjal seedlings, respectively. In terms of success ratio of transplanting, the average for the three kinds of seedlings was 89.59%. The pick-up device satisfactorily grasped and removed each seedling from the protray and transported it to the place where it would be precisely transplanted in the field.

Key words : Protray plug seedlings, Gripping mechanism, Automatic transplanter, Success ratio.