Design and Simulation of the Climbing Mechanism for a Multi-Point Embracing Coconut Harvesting Robot

Shichao Han; Siyu Wang; Haoyu You

doi:10.54097/gm3kyk92

Authors

Shichao Han
Siyu Wang
Haoyu You

DOI:

https://doi.org/10.54097/gm3kyk92

Keywords:

Coconut harvesting robot; Crawler climbing; Multi-point embracing; Elastic conformal adaptation

Abstract

To address the high risks associated with manual harvesting of tall coconut trees, as well as the insufficient trunk diameter adaptability and poor conformal stability of existing climbing devices, a multi-point embracing climbing mechanism for a coconut harvesting robot was designed to enhance its adaptability to varying trunk diameters and locally irregular trunk surfaces. The mechanism comprises three crawler units arranged circumferentially around the trunk, each equipped with two driving tracks. An electric push rod drives a bionic embracing arm to achieve active clamping and positional adjustment for varying trunk diameters. Within the tracks, support wheels are designed to swing around a fixed axis, with elastic restoring forces provided by tension springs. This configuration enables the tracks to accommodate local protrusions and variations in the surface curvature of the trunk. A mechanical model for the vertical climbing of the robot was established to analyze the clamping force, anti-slip stability, and driving parameters. Furthermore, three-dimensional simulation analyses were conducted under varying trunk diameters, local protrusions, and key load-bearing structures.

References

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