From beetle to bot: bioinspired design of robotic grippers based on stag beetle mandible biomechanics

Conventional rigid grippers remain the most-used robotic grippers in industrial assembly tasks. However, they are limited in their ability to handle a diverse range of objects. This study draws inspiration from nature to address these limitations, employing multidisciplinary methods, such as computer-aided design, parametric modeling, finite element analysis, 3D printing, and mechanical testing. Computational analysis of three distinct mandible morphs from the stag beetle Cyclommatus mniszechi revealed that key geometric features—specifically mandible curvature and denticle arrangement—govern a functional trade-off between grasping ability and structural safety. This analysis identified a specific morphology optimized for superior grabbing performance, which served as the template for our design. Leveraging these biological principles, we used parametric modeling to design, and 3D printing to fabricate, a series of novel, mechanically intelligent grippers. Mechanical testing of these prototypes validated our design approach, demonstrating that specific modifications to curvature could significantly enhance the gripper’s load-bearing capacity while minimizing object damage. This work establishes a clear pathway from biomechanical analysis to engineered application, offering a robust and cost-efficient blueprint for developing next-generation grippers that operate effectively without complex sensing or actuation systems for tasks in manufacturing, logistics, and healthcare.