Experimental Study on Clamping Safety Margin of a Banana Stem Gripper

Abstract

Banana stem gripper is an important component of banana harvesting robot. Since banana bunches is heavy, and easy to slide and fall during robot harvesting, we should figure out the clamping safety margin of banana stem gripper for reliability manipulation. The clamping safety margin is the ratio of maximum load-bearing capability to object's weight under given applied clamping force. It is able to evaluate special gripper's clamping ability and useful for optimizing robot gripper's structure parameters. A test platform is designed and fabricated for studying banana stem clamping safety margin. It consists of a rack, two cylinders, a straight-line moving mechanism, two clamping bases, etc. Different types of clamping part and clamping forces are tested and compared to evaluate their clamping safety margins. Compared to profile clamping part, the destructive puncture is more suitable for clamping and spends lower clamping force. Also, the relationship between the safety margin and clamping force are given, which is significant for selecting the proper clamping force of banana stem robot grippers.